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    * General Manager ICT Pvt. Ltd., A-9, Green Park, New Delhi 110 016, e-mail : [email protected]

    ** General Manager e-mail : [email protected]

    Written comments on this paper are invited and will be received upto 5 November 2009.

    Paper No. 555

    RCC BOX CULVERT - METHODOLOGY AND

    DESIGNS INCLUDING COMPUTER METHOD

    B.N. SINHA* & R.P. SHARMA**

    ABSTRACT

    Culverts are required to be provided under earth embankment for crossing of water course like streams, Nallas

    across the embankment as road embankment can not be allowed to obstruct the natural water way. The culverts

    are also required to balance the ood water on both sides of earth embankment to reduce ood level on one side

    of road thereby decreasing the water head consequently reducing the ood menace. Culverts can be of different

    shapes such as arch, slab and box. These can be constructed with different material such as masonry (brick, stone

    etc) or reinforced cement concrete.

    Since culvert pass through the earthen embankment, these are subjected to same trafc loads as the road carries

    and therefore, required to be designed for such loads. This Paper deals with box culverts made of RCC, with and

    without cushion. The size, invert level, layout etc. are decided by hydraulic considerations and site conditions.

    The cushion depends on road prole at the culvert location. The scope of this Paper has been further restricted

    to the structural design of box. The structural design involves consideration of load cases (box empty, full, sur-

    charge loads etc.) and factors like live load, effective width, braking force, dispersal of load through ll, impact

    factor, co-efcient of earth pressure etc. Relevant IRC Codes are required to be referred. The structural elements

    are required to be designed to withstand maximum bending moment and shear force. The Paper provides full

    discussions on the provisions in the Codes, considerations and justication of all the above aspects on design.

    Proper design covering these aspects has also been given in the Annexure. To our knowledge, these matters have

    neither been covered in any text book nor in any special publication at one place.

    1 INTRODUCTION

    It is well known that roads are generally constructed

    in embankment which come in the way of natural ow

    of storm water (from existing drainage channels). As,

    such ow cannot be obstructed and some kind of cross

    drainage works are required to be provided to allow

    water to pass across the embankment. The structures to

    accomplish such ow across the road are called culverts,

    small and major bridges depending on their span which

    in turn depends on the discharge. The culvert cover upto

    waterways of 6 m (IRC:5-19981) and can mainly be of

    two types, namely, box or slab. The box is one which

    has its top and bottom slabs monolithically connected

    to the vertical walls. In case of a slab culvert the top

    slab is supported over the vertical walls (abutments/

    piers) but has no monolithic connection between them.

    A box culvert can have more than single cell and can be

    placed such that the top slab is almost at road level and

    there is no cushion. A box can also be placed within

    the embankment where top slab is few meters below theroad surface and such boxes are termed with cushion.

    The size of box and the invert level depend on the

    hydraulic requirements governed by hydraulic designs.

    The height of cushion is governed by the road prole

    at the location of the culvert. This Paper is devoted to

    box culverts constructed in reinforced concrete having

    one, two or three cells and varying cushion including no

    cushion. The main emphasis is on the methodology of

    design which naturally covers the type of loading as per

    relevant IRC Codes and their combination to produce

    the worst effect for a safe structure. The IS:1893-1984(Clause 6.1.3) provide that box culverts need not be

    designed for earthquake forces, hence no earthquake

    forces are considered. Although box of maximum three

    cells has been discussed but in practice a box culvert can

    have more cells depending on the requirements at site.

    Culverts are provided to allow water to pass through

    Journal of the Indian Roads Congress, October-December 2009

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    191RCCBOXCULVERT- METHODOLOGYANDDESIGNSINCLUDINGCOMPUTERMETHOD

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    the co-efcient of earth pressure shall be more than

    the active condition. In case of box since it is conned

    with earth from both sides the state of earth shall be at

    rest and a co-efcient more than the active pressure is

    normally adopted in the design. The earth is lled after

    construction of the box further the box is not in a position

    to move/yield therefore the pressure shall be at rest. The

    value is designers choice.

    The co-efcient of earth pressure in case of box is

    taken to be 0.333 for a soil having = 30 equivalent

    to active condition by many authors in their books of

    design. Some authors take this value = 0.5 for normal

    soil having = 30. A typical box has been designed

    keeping all factors to be same for the two values of earth

    pressure co-efcient. It is seen that these co-efcient

    even when taken differently have little effect on the

    over all design of the section. To bring out differencein more appreciable form the two designs are compared

    in Table 1. (refer Annex A and Annex B). It is observed

    that difference in design of culvert without cushion

    is marginal. However, box with cushion shows more

    difference.

    Considering the situation typical to the box, it is close

    to at rest condition and a co-efcient higher than active

    pressure should be taken. For practical considerations

    a value of 0.5 can be taken for earth pressure. Whereas,

    there is no point of difference in taking this value for

    culverts with cushion, some reservations are shown

    where braking force is taken to act on culverts without

    cushion, where the box is assumed to deform pressing

    against the ll earth on one side and the pressure can be

    different on two sides, at least it may tend to be active

    on the side the box is tilting away from the ll. In design

    this difference of earth pressure on two sides of box is

    not taken, as the pressure on the passive side, which

    depends on amount of deformation of culvert, can not

    be evaluated within reasonable limits. However, the

    earth pressure on both sides of box before and after

    Table 1 Comparison of Moment in kN.m for different Earth Pressure Co-efcient keeping all other

    parameters same

    Box Designation [1/3 x 3/ 5] [1/3 x 3/ 0]

    Member Ka = 0.333 Ka = 0.5 Ka = 0.333 Ka = 0.5

    Support A&B 71.3 82.5 115.8 119.9

    Support C&D 83.8 95.5 79.1 83.6

    Mid-span AB 80.5 69.3 90.9 86.9

    Mid-span DC 85.5 79.3 52.2 47.7

    deformation can be assumed to be at rest/active pressure

    as the earth pressure co-efcient has little over all effect

    on the structural sizes of box members as already shown

    in Table 1 and explained under sub para 2 above. For

    A,B,C & D refer Annex A.

    3 EFFECTIVE WIDTH

    Effective width in the run of culvert (length across span)

    is expected to be affected by a moving live load. This

    width plays a signicant role as far as consideration of

    live load in the design of culvert. Where however, there

    is large cushion the live load gets dispersed on a very

    large area through the ll and the load per unit area

    becomes less and does not remain signicant for the

    design of box, particularly in comparison to the dead

    load due to such large cushion. In case of dead load or

    uniform surcharge load the effective width has no roleto play and such loads are to be taken over the entire

    area for the design.

    Effective width plays an important role for box without

    cushion as the live load becomes the main load on the

    top slab and to evaluate its effects per unit run for design

    as a rigid frame, this load is required to be divided by

    the effective width. As such evaluating effective width

    correctly is of importance. The relevant IRC Codes,

    other Codes, books, theory/concepts are at variance

    as far as effective width is concerned and requires

    discussions at some length.

    It is required to understand the concept behind effective

    width. Basically, it is the width of slab perpendicular to

    the span which is affected by the load placed on the top

    of slab. It shall be related to the area of slab expected

    to deform under load. It can be well imagined that this

    area of slab which may get affected will depend on how

    the slab is supported whether in one direction or both

    directions and secondly on the condition of support that

    is whether free or continuous or partially or fully xed.

    It can also be imagined that the width shall be larger if

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    slab is allowed to slide over support under the load as

    in case of freely supported, and the same will reduce if

    the slab is restrained from sliding and more the restraint

    the less shall be the width. In this view the effective

    width shall be least for fully xed and gradually increase

    for partially xed, increase further for continuous slab

    and shall reach maximum for slabs freely supported at

    ends. Where support on one side is different than on

    the other side the effective width should be obtained

    taking this fact in consideration. The distance of the load

    from the near support affects effective width, more the

    distance larger will be the effective width and will reach

    highest when the load is at center. The ratio of breadth

    (unsupported edges) and the span also affects effective

    width. All factors mentioned above need to be taken

    into account while obtaining the effective width.

    The IRC:21-20006 Clause 305.16 gives an equationfor obtaining effective width for simply supported and

    continuous slab for different ratio of over all width verses

    span for these two kinds of supports. The Code does not

    provide if one of the support is continuous while other is

    simply supported. The Code is silent for other types of

    supports such as xed or partially xed. Some designers

    use this formula and factors for continuous slab is taken

    valid for partially restrained support in a situation like

    box culvert. This does not appear to be in order. The

    reasons for this can be better realized by the explanations

    given in sub para 3 above. Nevertheless, effective widthneed to be obtained in box type structure also to evaluate

    affected area by moving load for considering these in

    the design. The design of a typical box of designation

    [1/3x3/0] has been done by obtaining effective width

    considering varying value of such as 2.6, 2.0, 1.0, 0.9,

    0.8 & 0 (Table 2). The moment and consequently the

    main reinforcement varies signicantly with value of ,

    the amount of reinforcement increases with decreasing.

    This is because smaller gives smaller effective

    width and, therefore, more moment and shear per unit

    length (run) of box, as all other dimensions are same

    reinforcement increases with decrease in value of . Itis further observed that MORT&H7provision in their

    standard drawings for a similar culvert and situation falls

    between value 0 to 1.0. This also indicates that taking

    value of equivalent to that for continuous slab given

    in IRC:21-20006shall not be correct for box structure. It

    may be seen that considering any value for shall affect

    mainly the top slab. Bottom slab due to dispersal through

    walls and box with cushion due to dispersal through ll

    to even the top slab, are not affected much.

    The live load moment and shear for the top slab can be

    obtained per unit run of box considering effective width

    for an assessed value of . For the bottom slab the live

    load shall disperse through the walls and such dispersed

    area could over lap for different wheels, therefore,

    a uniform distributed load per unit run of box couldbe obtained on this basis and used in the analysis. In

    other words the effect of live load on bottom slab shall

    be as in case of large cushion for top slab explained

    under sub para 1. As far as walls are concerned the

    loads are uniform and pressure etc all are same per unit

    run of culvert and effective width has no role to play.

    The braking force acts on the box structure and taking

    effective width for top slab different than bottom slab

    shall make the analysis cumbersome and may not be

    practical. The AASHTO also advocates dispersal for

    bottom slab. Jaikrishna and O.P. Jain8in his book has

    considered dispersal of live load through walls forbottom slab at 45. However, the MORT&H7Standard

    design do not tally with this provision.

    The AASHTO9for Standard Specications for Highway

    Bridges 17th Edition 2002, provides at para 16.6.4.3

    under RCC Box that The width of top slab strip used

    for distribution of concentrated wheel loads may be

    increased by twice the box height and used for the

    distribution of loads to the bottom slab. This conrms

    what is mentioned in sub para 5 and is alright. However,

    any such dispersal for bottom slab different than top

    slab shall not be practical when braking force effect isto be taken, which shall have to be for the same run of

    the box structure as a whole (refer para 4).

    4 BRAKING FORCE

    This is another area where opinion of the designers vary

    in two ways rstly, whether braking force caused by

    moving loads shall deform the box structure and should

    therefore be considered in the design of box. Secondly,

    if it is to be considered what effective width should be

    taken to obtain force and moment per unit run of box. Of

    course the braking force will affect the global stability

    and change the base pressure to some extent. The IRC

    Code is silent as far as box is concerned. It will be in

    order to neglect effect of braking force on box having

    large cushion. In such situation the braking effect will

    be absorbed by the cushion itself and no force will be

    transmitted to the box beneath. Question will, however,

    arise up to what cushion height no braking force need

    be taken. This height generally is taken to be 3 m. Thus

    no braking force for cushion height of 3 m and more

    and full braking force for no cushion, for intermediate

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    heights of cushion the braking force can be interpolated.

    There is no literature on this aspect and the Code is also

    not specic for box, however, IRC:6-200010Clause211.7 mentions that no effect be taken at 3 m below

    bed block in case of bridge pear/abutment. Our further

    discussions shall be on box without cushion as far as

    braking force is concerned.

    Braking force by the moving loads on top slab of box

    having no cushion shall act on the box structure and

    shall deform the box. The question is what length of box

    can be considered to share this braking force. In another

    words what effective width of box shall be taken to obtain

    braking force per unit run of box. One way is to take the

    effective width of box same as considered for vertical

    effect of moving loads, discussed under para 3 above.

    The arguments in favor of this is the same which holds

    for effective width for vertical deformation of top slab

    under moving loads. Vertical effect as well as braking

    effect both are product of the same loads and can affect

    the same run of box. In absence of specic provision

    in Codes in this regard the same effective width can be

    taken for both effects for the design of box.

    The box is considered a rigid frame for analysis and

    design. The braking force can be taken to act on the top

    junction of the box causing moment at xed ends of bothwalls and the top and bottom slabs having zero xed end

    moments (IRC:6-200010 Clause 214.7). The moment

    distribution is carried out and distributed moments are

    obtained at supports. This moment shall be added to the

    maximum moment under different conditions for other

    loads to get nal design moments at supports. It may

    be mentioned here that the mid span moments are not

    affected by braking force moments as the same being

    zero at mid span even after distribution. Also braking

    force can act in either direction hence the moment

    at junctions can reverse in sign and thus needs to bearithmetically added to moments due to vertical effect

    of loads for the design.

    It is seen that box without cushion if designed ignoring

    braking force effect gives smaller thickness and very

    less reinforcement compared to the MORT&H7standard

    designs for similar culvert. In case of 2 m x 2 m box the

    distributed moment at junctions works out to about 60%

    if braking force is not considered, consequently gives

    Table 2 Shows Moment and Reinforcement for Different Values of Keeping other Parameters Constant as

    given here: Box [1/3x3/ 0], Ka = 0.5, steel = Fe 415, concrete = M25, thickness of slabs and walls = 420 mm,

    Concrete Unit Weight=24 kN/m3, Soil Unit Weight=18 kN/m3, Wearing Course Weight = 2 kN/m

    Design values

    Moment in kN.m. Area of reinforcement in mm

    MAB

    (Support)

    MDC

    (Support)

    MAB

    (Mid-

    span)

    MDC

    (Mid-

    span)

    Support

    A & B

    Support

    D & C

    MAB

    (Mid-

    span)

    MDC

    (Mid-

    span)

    As per

    design

    carried out

    0 119.8 83.6 87.0 47.7 1834.8 1375.3 1331.4 1422.8

    0.8 86.4 72.3 61.3 54 1322.6 1189.1 938.1 887.6

    0.9 83.1 70.9 58.9 43.6 1272.0 1166.4 901.8 717.8

    1.0 80.4 67.0 56.8 46.4 1231.3 1102.1 870.7 726.4

    2.0 65.0 64.5 45.2 41.69 995.2 1051.4 692.8 685.8

    2.6 59.8 62.8 41.2 41.1 916.0 1033.6 630.4 676.2

    As per

    Standard

    design of

    MORTHS

    Standard

    design

    compares

    with values

    between

    = 0 to 1

    Standard

    design

    provide only

    reinforce-

    ment as

    shown

    _ _ _ 1398 1398 1005.3 1570.8

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    lesser thickness and reinforcements. In case of box of

    size 6 m x 6 m the braking force effect if not taken gives

    lesser moment say around 30% less (Table 3). That is for

    larger size of box the effect of braking force becomes

    lesser. It, therefore, suggests that for smaller size box

    braking force effect has to be taken in design. When,

    however, the size is big the braking force will affect the

    design marginally. In all cases for box without cushion

    braking force need to be considered in the design.

    5 IMPACT OF LIVE LOAD

    Moving loads create impact when these move over the

    deck slab (top slab). The impact depends on the class

    and type of load. The IRC:6-2000 Code gives formula to

    obtain impact factor for different kind of loads by which

    the live load is to be increased to account for impact.

    The box without cushion where the top slab will be

    subjected to impact is required to be designed for live

    loads including such impact loads. Any such impact is

    not supposed to act on box with cushion. Hence no such

    impact factor shall be considered for box with cushion.

    The impact by its very nature is not supposed to act at

    lower depth and no impact is considered for the bottom

    slab of the box. It does not affect the vertical walls of

    the box and not considered in the design.

    Table 3 Comparison of Designs without Braking Force with the Design when Braking Force is Considered

    Culvert

    Designation[1/6 x 6/ 0] [1/2 x 2/ 0]

    LocationSupport

    A

    Support

    DMid AB Mid CD

    Support

    A

    Support

    DMid AB Mid CD

    M o m e n t w i t h

    braking force, in

    kN.m.

    390 286 244.5 165.2 44 27 42.8 19

    Moment without

    braking force, in

    kN.m.

    301 184 244.5 165.2 27.5 8 42.8 19

    Reinforcement

    with braking force

    in mm

    3378 2187 2118 1263 835 504 813 355

    Reinforcement

    without braking

    force in mm

    2607 1407 2118 1263 522 149 813 355

    Standard Design

    Reinforcement in

    mm

    2576 3142 3020 2576 1118 1118 804 804

    The IRC:6-200010, Code Clause 211.7 species that

    for calculating pressure on the bearings and on the

    top surface of the bed blocks, full value of appropriate

    impact percentage be allowed. But for design of pier,

    abutment below the level of bed block, the appropriate

    impact percentage shall be multiplied by the factor given

    therein. Accordingly, the impact is to be reduced to 50%

    below bed block and zero at 3 m below, proportionately

    reducing between this height. Although these provisions

    are for bridges but can be applied in case of box structure

    in absence of any specic provision in the Code for box

    in this regard.

    The AASHTO9 at para 3.8.1.2 species that impact

    shall not be included for culverts having 1m or more

    cover. This, however, will be on lower side compared

    to considering zero impact for a cover (cushion) of 3 m.

    It is, therefore, suggested that considering full impacton top slab without cushion and zero impact for 3m

    cushion and interpolating impact load for intermediate

    height of cushion is on conservative side and can be

    safely adopted.

    6 SHEAR STRESS

    The box is designed for maximum moment for its

    concrete section and reinforcements. It is checked for

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    shear at the critical section and if it exceeds permissible

    shear stress for the size of section; mix of concrete and

    percentage of reinforcements, the section has to be

    increased to bring shear stress within the permissible

    limit. Alternatively, the reinforcement can be increased

    to increase allowable shear strength. The third option is

    to provide stirrups to counter excess shear stress. This

    may have to be adopted in situation where thickness

    of slab cannot be increased due to certain restrictions.

    The top and bottom slabs are needed to be checked

    for shear. The vertical walls carry much less loads and

    shall be normally safe in shear, therefore, there is no

    need to check in shear. To make safe in shear one or

    any combination of increasing size, increasing tension

    reinforcement and/or providing shear stirrups can be

    adopted.

    It is important to note that IRC:21-20006under Clause304.7.1 has given table 12B. Permissible shear stress in

    Concrete for checking section for shear stress. The values

    given here have been drastically reduced compared to

    similar provision in previous Codes and practices. It is

    observed that the shear may govern the design of the

    section, in particular, box with large cushion.

    Critical section for shear is the section at effective depth

    from the face of support (face of wall). The effective

    depth is the distance of center of tension reinforcement

    from the extreme compression face. Where, however,

    haunch is provided, an extra depth due to haunch withina slope of 1V:3H can be considered to increase the

    effective depth (IRC:21-20006 Clause 305.5.3). This

    should be taken into account while deciding the critical

    section. However, for shear stress at the critical section,

    the effective depth only without effect of haunch be

    taken.

    In situation when the section is required to be provided

    with shear reinforcement which otherwise is not safe

    in shear and only this option is to be adopted, the shear

    capacity of the section based on permissible shear stress,

    which is based on percentage of tension reinforcementand concrete mix, is obtained. Shear capacity of

    section is deducted from the shear force obtained at

    critical section and shear reinforcement is calculated

    for the balance shear force and accordingly provided

    in addition to other steel. It is obvious that such shear

    reinforcement shall be required for the whole length of

    box but the distance along the span from the face of wall

    up to which these shear reinforcement is to be provided

    shall have to be calculated. As the shear is reducing

    away from the face of wall, the distance where the

    shear force becomes equal to shear capacity of section

    (without shear reinforcement) is obtained. The shear

    reinforcement shall be provided up to this distance on

    both sides of box from near wall. The design at annexure

    will further elucidate this.

    The box is to be safe in bending as well as in shear. The

    box can be designed for maximum shear and checked for

    bending, particularly where shear is expected to govern

    the design as for box having large cushion. However, the

    tension reinforcement has to be provided for the bending

    moment in any case.

    7 DISTRIBUTION REINFORCEMENTS

    The Code IRC:21-20006, in Clause 305.18 provides

    for distribution reinforcements. The distributionreinforcement shall be such as to produce a resisting

    moment in direction perpendicular to the span equal

    to 0.3 times the moment due to concentrated live loads

    plus 0.2 times the moment due to other loads such as

    dead load, shrinkage, temperature etc.

    In box, moment due to live loads and dead loads

    are obtained considering both the loads together. It,

    therefore, becomes cumbersome to separate these

    two moments to apply above provision of the Code

    to calculate distribution reinforcements. To make it

    convenient and easy a combined factor for both theloads, based on weighted average in proportion of their

    magnitude, can be worked out to apply for the design.

    This has been adopted in the typical design provided

    in Annexure.

    8 LOAD CASES FOR DESIGN

    Mainly three load cases govern the design. These are

    given below (Ramamurtham11)

    a) Box empty, live load surcharge on top slab of box

    and superimposed surcharge load on earth ll.

    b) Box inside full with water, live load surcharge on

    top slab and superimposed surcharge load on earth

    ll.

    c) Box inside full with water, live load surcharge on

    top slab and no superimposed surcharge on earth

    ll.

    The above mentioned load cases are to be examined for

    box with cushion and without cushion. In case of box

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    The design of the single cell box of size 3 m x 3 m with

    5 m cushion have also been done by using STAAD. Pro

    computer software and moment and shear as obtained

    are compared with that calculated by manual method

    of design. These are given in Table 4. It is seen that

    they compare well. The design of box can, therefore,

    be carried out by STAAD. Pro as well. Input data sheet,

    bending moment diagram and shear force diagram as

    obtained by STAAD. Pro are given in the Paper at

    Annex C. The analysis part to get these design moment

    and shear values for relevant members which runs in

    number of pages, is not given in the Paper as it will add to

    the length without serving much purpose. The STAAD.

    Pro is well known computer software commonly used.

    Box without cushion : Annex A

    Box with cushion : Annex B

    Design of box with

    cushion by STAAD.Pro. : Annex C

    Drawing of the box culverts

    for construction purposes : Annex D

    10 CONCLUSIONS

    i) Box for cross drainage works across high

    embankments has many advantages compared to

    a slab culvert.

    ii) It is easy to add length in the event of widening of

    the road.

    iii) Box is structurally very strong, rigid and safe.

    iv) Box does not need any elaborate foundation and can

    easily be placed over soft foundation by increasing

    base slab projection to retain base pressure within

    safe bearing capacity of ground soil.

    v) Box of required size can be placed within the

    embankment at any elevation by varying cushion.

    This is not possible in case of slab culvert.

    vi) Right box can be used for ow of water in skew

    direction by increasing length or providing edge

    beam around the box and it is not necessary to

    design skew box.

    vii) Easy to construct, practically no maintenance, can

    have multi-cell to match discharge within smaller

    height of embankment.

    viii) Small variation in co-efcient of earth pressure has

    little inuence on the design of box particularly

    without cushion.

    ix) For culverts without cushion (or little cushion)

    taking effective width as per provision in

    IRC:21-2000 corresponding to for continuousslab shall not be correct. It is likely to provide

    design moments and shear on lower side hence

    not safe.

    x) For box without cushion braking force is required

    to be considered particularly for smaller span

    culverts. Further for distribution of braking force

    effects the same effective width as applicable for

    vertical application of live load shall be considered.

    If braking force is not considered or distributed

    over the whole length of box (not restricted withinthe effective width) the design shall be unsafe.

    xi) It may be seen that affects effective width,

    mainly applicable for the top slab (particularly

    for box without cushion) and braking force. As

    regards bottom slab and top and bottom slabs of

    box with cushion due to dispersal of loads either

    through walls or through lls effective width loses

    its applicability.

    xii) The design of box is covered by three load cases

    dealt in this paper. The forth situation when wholebox is submerged under water, provide design

    moments etc less than given by the three load cases

    hence need not be considered.

    xiii) The design of box with cushion done by STAAD.

    Pro computer software compares very close to

    manual design.

    11 ACKNOWLEDGEMENTS

    We are thankful to ICT Pvt. Ltd. A-8, Green Park,

    New Delhi-110 016 for using its appliances to bring

    this paper to the present shape. They are grateful to

    Shri A.D. Narain, Executive Director, ICT for his help

    in going through the Paper and giving suggestions for

    improvements. They are also thankful to S/Shri Jetendra

    Kumar Arya and Harjot Singh, Deputy Managers

    (Highways) for preparing AUTOCAD drawings and

    Mrs. Sonia Kumar, Deputy Manager(IT) for formatting

    and typing.

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    REFERENCES

    1. IRC:5-1998, Standard Specications and Code of

    Practice for Road Bridges, Section I.

    2. IS:1893-1984, Criteria for Earthquake Resistant Design

    of Structures, Fourth Revision.

    3. IRC:78-2000, Standard Specications and Code of

    Practice for Road Bridges, Section VII, Foundation

    and Substructure.

    4. Terzaghi and Karl, Theoretical Soil Mechanics, John

    Wiley and Sons, ING. Tenth Printing, 1962.

    5. Gulhati, Shashi K. and Datta, Manoj, Geotechnical

    Engineering, Tata McGraw-Hill Publishing Company

    Limited, 2005.

    6. IRC:21-2000, Standard Specications and Code of

    Practice for Road Bridges, Section III.

    7. MORT&H (Ministry of Road Transport and Highways),

    Standard Drawings for Box Cell Culverts, New Delhi,

    2000.

    8. Krishna, Jai and Jain, O.P., Plain and Reinforced

    Concrete, Volume II, Nem Chand & Bros., Roorkee(U.P.), 1966.

    9. AASHTO (American Association of State Highways

    and Transportation Ofcials), Standard Specications

    for Highway Bridges, 17th Edition, 2002.

    10. IRC:6-2000, Standard Specications and Code of

    Practice for Road Bridges, Section II.

    11. Ramamurtham, S., Design of Reinforced Concrete

    Structures, Dhanpat Rai Publishing Company, Tenth

    Edition, 1985.

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    1 SALIENT FEATURES

    Clear span 3 m Concrete grade M25 = 25 Mpa

    Clear height 3 m Steel grade Fe 415 = 415 Mpa

    Top slab thickness 0.42 m Sc (Concrete) 8.33 Mpa

    Bottom slab thickness 0.42 m St (Steel) 200 Mpa

    Side wall thickness 0.42 m Modular ratio 10

    Unit weight of concrete 24 kN/m3 n (for depth of neutral axis) 0.294

    Unit weight of earth 18 kN/m3 j (for effective depth) 0.902

    Unit weight of water 10 kN/m3 k (for moment of resistance) 1.105 Mpa

    Co-efcient of earth pressure at rest 0.5 All dimensions are in meter unless

    Total cushion on top 0.0 m mentioned otherwise.

    Thickness of wearing coat 0.065 m All moments are in kN. m and shear forceCarriageway 8 lane divided in kN unless mentioned otherwise.

    ANNEX A

    (Para 2)

    RCC BOX CULVERT, DESIGNATION: [1/3 x 3/0]

    Fig.1 Cross Section of Box (All dimensions are in m)

    Fig. 2 Dispersal under Class 70R (T) One Track

    (All dimensions are in m)

    2 LOAD CALCULATION

    2.1 Top Slab

    2.1.1Dead Load

    (a) Weight of wearing course

    = 0.065 x 22 = 1.43 kN/m

    Adopt minimum of 2 kN/m as per MOST

    Specication

    (b) Self weight of top slab

    = 0.42 x 24 = 10.08 kN/m

    (c) Total = 12.08 kN/m

    2.1.2Live Load

    Consider moving load of 70R(T). The dispersal

    and position of load shall be as under:

    A B

    D C

    Dispersal perpendicular to span

    = 0.84 + 2 x 0.065 = 0.97 m

    Dispersal in span direction

    = 4.57 + 2t +2d = 4.57 + 0.13 = 4.70 m

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    Note :

    1) Since the length of wheel is more than total width

    of box at top that is 3.84 m further dispersal by

    2d shall not be possible, hence not taken. In case

    where the length of load is less than the width ofbox but works out more when 2d is added, the

    dispersed length shall be restricted to top width of

    box.

    2) As the load of wheel after dispersal does not over

    lap, both wheels need to be taken separately.

    3) For dispersa l refer IRC:21- 2000 Clause

    305.16.3.

    4) Impact as per IRC:6-2000 Clause 211 shall be

    taken.

    5) This shall be the load when is zero and live loadis taken to disperse through wearing coat only.

    Load per unit area

    = 350/4.7 x 0.97 = 76.77 kN/m

    Impact factor for 70R(T) shall be 25 % as per Clause

    211.3 (a) (i) of IRC:6-2000

    Load including impact = 95.96 kN/m

    2.1.3 Total Load(D.L.+L.L.)

    = 12.08 + 95.96 = 108.04 kN/m

    2.2 Bottom Slab

    2.2.1Dead Load

    Load from top slab = 12.08 kN/m

    Load of walls = 2 x 3 x 0.42 x 24/3.84 = 15.75 kN/m

    Total Load = 27.83 kN/m

    2.2.2Live Load

    The Live Load on top of box will disperse through

    walls and when arranged on the carriage way

    (lengthwise of the box) the distribution shall be as

    under :

    Fig. 3 Dispersal of wheel loads on bottom slab

    (All dimensions are in m)

    Fig. 4 Force Diagram for Wall (All dimensions are in m)

    Taking reduction for simultaneous additional lane

    loadings at 20% (refer IRC:6-2000, Clause 208), the

    load on unit area of bottom slab for two track loading

    works out to 20.51 kN/m, if one track without reduction

    is considered restricting area of dispersal the load perunit area works out 19.8 kN/m. The dispersed live load

    on bottom slab can be taken to be 21 kN/m.

    2.2.3 Total Load (DL +LL) = 27.83 + 21 = 48.83 kN/

    m Adopt 50 kN/m

    2.3 Side Wall

    2.3.1Case 1: Box empty, earth pressure with live load

    surcharge equivalent to 1.2 m height of earth on

    both sides lls.

    Fig. 5 Force Diagram for Wall (All dimensions are in m)

    Earth Pressure at base due to live load surcharge

    = 1.2 x 18 x 0.5 = 10.8 kN/m

    Earth Pressure at base due to earth ll= 18 x 3.42 x 0.5 = 30.78 kN/m

    2.3.2Case 2 : Box full, Live load surcharge on side

    ll.

    Water pressure inside and out side will balance each

    other and hence not taken.

    Earth Pressure at base due to live load surcharge

    = 10.8 kN/m

    Earth Pressure at base due to submerged earth

    = (18-10) x 3.42 x 0.5 = 13.68 kN/m

    2.3.3Case 3 : Box full, no live load surcharge on side

    ll.

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    Fig. 6 Force Diagram for wall (All dimensions are in m)

    Earth Pressure at base due to submerged earth

    = 8 x 3.42 x 0.5 = 13.68 kN/m

    Earth Pressure due to live load = 0

    2.4 Base Pressure

    2.4.1Dead load

    Load from top slab and walls including wearing

    course = 27.83 kN/m

    Self weight of bottom slab

    = 0.42 x 24 = 10.08 kN/m

    Total Load = 37.91 kN/m

    2.4.2Live Load

    There is no live load except coming from top slab

    without impact = 21 kN/m

    2.4.3Base pressure = 58.91 kN/m (Is safe for a S.B.C

    of 150 kN/m)

    3 MOMENT CALCULATION

    3.1 Top Slab

    Fixed end moment due to dead load

    = 12.08 x 3.42 x 3.42/12 = 11.77

    Fixed end moment due to live load

    = 95.96 x 3.42 x 3.42/12 = 93.55

    Total xed end moment = 105.30 kN.m

    Mid span moment due to dead load

    = 12.08 x 3.42 x 3.42/8 = 17.66

    Mid span moment due to live load

    = 95.96 x 3.42 x 3.42/8 = 140.30

    Total Mid Span Moment = 157.96 kN.m

    3.2 Bottom Slab

    Fixed end moment due to dead load = 27.13

    Fixed end moment due to live load = 20.5

    Total xed end moment = 47.63 kN.m

    Mid span moment due to dead load = 40.69

    Mid span moment due to live load = 30.75

    Total Mid Span Moment = 71.45 kN.m3.3 Side Wall

    3.3.1Case 1 : Box empty, surcharge load on side ll.

    F.E.M at top due to dead load

    = = 12

    F.E.M at top due to live load

    = 10.8 x 3.42 x 3.42/12 = 10.53

    Total F.E.M at top = 22.53 kN.m

    F.E.M at base due to dead load

    = = 18 kN.m

    F.E.M at base due to live load = 10.53

    Total F.E.M at base = 28.53 kN.m

    Mid span moment due to dead load

    = = 22.5

    Mid span moment due to live load

    = 10.8 x 3.42 x 3.42/8 = 15.79

    Total Mid Span Moment = 38.29 kN.m

    3.3.2 Case 2 : Box full, live load surcharge on side

    ll.

    F.E.M at top due to dead load

    = 13.68 x 3.42 x 3.42/30 = 5.33

    F.E.M at top due to live load = 10.53

    Total F.E.M at top slab = 15.86 kN.m

    F.E.M at base due to dead load

    =13.68 x 3.42 x 3.42/20 = 8

    F.E.M at base due to live load = 10.53

    Total F.E.M at bottom = 18.53 kN.m

    Mid span moment due to dead load

    = 13.86 x 3.42 x 3.42/16 = 10

    Mid span moment due to live load = 15.79

    Total Mid Span Moment = 25.79 kN.m

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    3.3.3 Case 3 : Box full, no live load surcharge

    F.E.M at top due to dead load = 5.33

    F.E.M due to live load = 0

    Total F.E.M at top = 5.33 kN.m

    F.E.M at base due to dead load = 8F.E.M at base due to live load = 0

    Total F.E.M at base = 8 kN.m

    Mid span moment due to dead load = 10

    Mid span moment due to live load = 0

    Total Mid Span Moment = 10 kN.m

    4 DISTRIBUTION FACTORS

    Junction Members 4EI/L =

    K d/L

    SUM

    4EI/L

    Distri-

    butionfactors

    A & B AB/AD,

    BA/BC

    K 0.423

    /3.42

    2K0.423

    /3.42

    0.5

    0.5

    C & D DA/DC,

    CD/CB

    K 0.423

    /3.42

    2K 0.423

    /3.42

    0.5

    0.5

    5 MOMENT DISTRIBUTION

    5.1 F.E.M Due to Dead Load

    MAB= MBA= 11.77 kN.m

    MDC= MCD= 27.13 kN.m

    MAD= MBC= 12 kN.m (case 1), 5.33 kN.m (case 2),

    5.33 kN.m (case 3)

    MDA= MCB= 18 kN.m (case 1), 8 kN.m (case 2),

    8 kN.m (case 3)

    5.2 F.E.M Due to Live Load

    MAB= MBA= 93.55 kN.m

    MDC= MCD= 20.50 kN.m

    MAD= MBC=10.53 kN.m (case 1),

    10.53 kN.m (case 2), 0 (case 3)

    MDA= MCB= 10.53 kN.m (case 1),

    10.53 kN.m (case 2), 0 (case 3)

    5.3 F.E.M Due to Total Load

    MAB= MBA= 105.32 kN.m

    MDC= MCD= 47.63 kN.m

    MAD= MBC= 22.53 kN.m (case 1),

    15.86 kN.m (case 2), 5.33 kN.m (case 3)

    MDA= Mcb

    = 28.53 kN.m (case 1),

    18.53 kN.m (case 2), 8 kN.m (case 3)

    5.4 A typical distribution is shown in Table 1. Results

    based on similar distribution for other combinationare given in Table 2.

    Table 1 Moment Distribution for Total Load for Top & Bottom Slabs and Case 1 Loads for Walls

    Joint A B C D

    Member AB AD BA BC CB CD DC DA

    D.F 0.500 0.500 0.500 0.500 0.500 0.500 0.500 0.500

    F.E.M -105.320 22.530 105.320 -22.530 28.530 -47.63 47.63 -28.530

    DIST. 41.39 41.39 -41.39 -41.39 9.55 9.55 -9.55 -9.55

    C.O. -20.69 -4.78 20.693 4.776 -20.693 -4.776 4.776 20.693

    DIST. 12.73 12.73 -12.73 -12.73 12.73 12.73 -12.73 -12.73

    C.O. -6.37 -6.37 6.367 6.367 -6.367 -6.367 6.37 6.367

    DIST. 6.37 6.37 -6.37 -6.37 6.37 6.37 -6.37 -6.37

    C.O. -3.18 -3.18 3.184 3.184 -3.184 -3.184 3.184 3.184

    DIST. 3.18 3.18 -3.18 -3.18 3.18 3.18 -3.18 -3.18

    C.O. -1.59 -1.59 1.592 1.592 -1.592 -1.592 1.592 1.592

    DIST. 1.59 1.59 -1.59 -1.59 1.59 1.59 -1.59 -1.59

    FINAL -71.89 71.89 71.89 -71.89 30.12 -30.12 30.12 -30.12

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    Table 2 Support Moments

    Load

    Distributed Moments at Supports

    RemarksCase

    MAB MDC MAD MDA

    (MDA) (MCD) (MBC) (MCB)

    Dead Load

    (1) (-) 10.72 23.74 10.72 (-) 23.74Load on top

    slab and

    bottom slab

    remains

    same in all

    cases, only

    load on side

    wall varies.

    Without

    braking Force

    (2) (-) 6.96 19.15 6.96 (-) 19.15

    (3) (-) 6.96 19.15 6.96 (-) 19.15

    Live Load

    (1) (-) 61.17 6.38 61.17 (-) 6.38

    (2) (-) 61.17 6.38 61.17 (-) 6.38

    (3) (-) 55.91 1.12 55.91 (-) 1.12

    Total Load

    (1) (-) 71.89 30.12 71.89 (-) 30.12

    (2) (-) 68.13 25.53 68.13 (-)25.53

    (3) (-) 62.87 20.27 62.87 (-) 20.27

    Maximum All cases 71.89 30.12 71.89 30.12

    Table 3 Mid Span Moments (Total Loads only)

    Member Case 1 Case 2 Case 3 Remarks

    MAB 157.96 - 71.89

    = 86.07

    157.96 - 68.13

    = 89.83

    157.96 - 62.87

    =95.09

    The Walls

    bends

    outwardly in

    all three casesMDC 71.45 - 30.12

    = 41.33

    71.45 - 25.53

    = 45.92

    71.45 - 20.27

    = 51.18

    MAD 38.29 - (71.89 + 30.12)/2

    = (-)12.72

    25.79 - (68.13 + 25.53)/2

    = (-) 21.04

    10 - (62.87 + 20.27)/2

    = (-) 31.57

    6 BRAKING FORCE

    6.1 LOAD: 70R(T),one wheel load is considered asthere is no over lapping.

    No impact as per IRC:6-2000 Clause 214.2.

    The braking force shall be 20 % for the rst laneload

    The braking force = 350 x 20/100 = 70 kN

    Load on top of box which will affect the box= 3.84 x 70/4.7 = 57.19 kN

    6.2 Moment Due to Braking Force

    MAD= MDA= MCB= MBC= 57.19 x 3.42/2= 97.79 kN.m

    The moments at top and bottom slab ends shall all

    be zero.

    After distribution of moments among all the

    members a moment of 48.9 kN.m is obtained at

    all ends. This moment is added to the maximum

    moments obtained for various combination of

    loadings at the ends of members to get design

    moments. Since braking force can also act from

    the reverse direction the moment at junctions are

    added irrespective of its sign.

    7 DESIGN OF SECTION

    7.1 Design Moments

    Table 4

    Load Case Maximum Distributed Moments at Supports

    MAB MDC MAD MDA

    Total Load Maximum of all cases 71.89 30.12 71.89 30.12

    Braking Force Distributed Moments at support 48.90 48.90 48.90 48.90

    Design Moments Support Moments including braking 120.79 79.02 120.79 79.02

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    Table 5 Moment and Reinforcement at Salient Section

    Member MAB MDC Mid span

    AB DC AD

    Moment in kN.m 120.79 79.02 95.09 51.18 31.57

    Area of steel in mm 1849.6 1299.8 1456 841.8 483.4

    7.2 Top Slab

    Maximum moment support/mid span including

    breaking = 120.79 kN.m

    Provided 362 mm is safe

    Check for Shear

    Shear force at deff

    from face of wall

    Shear Stress = 0.3247 N/mm > 0.312 N/mm

    permissible

    Permissible shear stress

    Increase tension steel to increase permissible shear

    stress.

    Required steel

    Hence, provide tension steel = 2076 mm in place

    of 1849.6 mm required for moment only.

    7.3 Bottom Slab

    B.M. (Max) = 79.02 kN.m

    Provided 337 mm is O.K.

    Check for Shear

    Shear Stress = 0.1613 N/mm < 0.2715 N/mm

    permissible, hence safe.7.4 Side Walls

    Moment at junction are same as slabs hence same

    tensile bars shall continue.

    Check for Shear

    = 18.460 + 17.545 = 36.01 kN

    RD = 18.468 + 35.090 = 53.56 kN

    S.F. at deff from

    = 53.56 11.92 4.45 = 37.19 kN

    S.F. at deff from

    = 30.796 kN

    Maximum Shear Stress (near base) = 0.100 N/mm (safe)

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    ANNEX B

    (Para 2)

    RCC BOX CULVERT, DESIGNATION: [1/3 x 3/5]1 SALIENT FEATURES

    Same as for box [1/3 x 3/0] given in Annex A,except the cushion which is 5.0 m total height

    above top slab.

    Fig. 1 Section of box culvert (All dimensions are in m)

    2 LOAD CALCULATION

    2.1 Top Slab

    2.1.1Dead Load

    a) Cushion = 5 x 18 = 90 kN/m

    b) Self weight of top slab = 0.42 x 24 =10.08 kN/m

    c) Total = 100.08 kN/m

    2.1.2Live Load

    Consider moving load of 70R (T). The dispersal

    and position of load shall be as under:

    Fig. 2 Dispersal of live load (All dimensions are in m)

    Dispersed area when 1 track loading is considered

    = 12.9 x 14.57 = 187.95 m

    Load per unit area when 1 track load (covering

    2-lanes) is considered = 700/187.95 = 3.724 kN/m

    Load per unit area when 2 track load (covering

    4-lanes) is considered

    = 1400 x 0.8/17 x 14.57 = 4.52 kN/m

    The larger of the two that is 4.52 kN/m is considered.

    Note:1) As the load of wheel after dispersal over lap both

    wheels need to be taken together.

    2) For dispersal refer IRC:21-2000 Clause 305.16.4.

    3) No impact as per IRC:6-2000 Clause 211.7 (c) due

    to cushion more than 3.0 m.

    2.1.3 Total load = 104.6 kN/m

    2.2 Bottom Slab

    2.2.1Dead Load

    Load from top slab including cushion

    =100.08 kN/m

    Load of walls

    = 2 x 3 x 0.42 x 24/3.84 = 15.75 kN/m

    Total load = 115.83 kN/m

    Live Load

    Load from top slab without impact

    = 4.52 kN/m

    Note: Some designers take further dispersal of live

    load from top slab. Although further dispersal through

    walls can not be denied but will affect only marginally,

    therefore, the load on top without impact can be taken

    for bottom slab also, which is already without impact

    in this case.

    2.2.2 Total load=115.83 + 4.52 = 120.35 kN/m

    2.3 Side Wall

    2.3.1Case 1: Box empty, earth pressure with live load

    surcharge equivalent to 1.2 m height of earth on

    both sides lls.

    Fig. 3 : Force diagram for vertical wall (All dimensions are in m)

    A

    D

    B

    C

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    Pressure due to live load surcharge

    = 1.2 x 18 x 0.5 = 10.80 kN/m

    Pressure due to earth surcharge

    = 5 x 18 x 0.5 = 45 kN/m

    Pressure due to earth ll

    = 0.5 x 18 x 3.42 = 30.78 kN/m

    Case 2 : Box full, Live load surcharge on side ll.

    Fig. 5 Force Diagram for wall

    Water pressure inside and outside will balance each

    other and hence not taken.

    Pressure due to live load surcharge

    = 10.8 = 10.8 kN/m

    Pressure due to earth surcharge

    = 45 = 45 kN/m

    Pressure due to submerged earth

    = 0.5 x (18-10) x 3.42 = 13.68 kN/m

    2.3.2 Case 3 : Box full, no live load surcharge on

    side ll.

    2.4 Base Pressure

    Dead load

    Load from top slab and walls including cushion

    = 115.83 kN/m

    Self weight of bottom slab= 0.42 x 24 =10.08 kN/m

    Total Load = 125.91 kN/m

    Live Load

    There is no live load except coming from top slab

    without impact = 4.52 kN/m

    2.4.1Base pressure = 130.43 kN/m

    (Is safe for a S.B.C of 150 kN/m)

    3 MOMENT CALCULATION

    3.1 Top Slab

    Fixed end moment due to dead load

    = 100.08 x 3.42 x 3.42 /12 = 97.55 Fixed end moment due to live load

    = 4.52 x 3.42 x 3.42/12 = 4.41

    Total xed end moment = 101.96 kN.m

    Mid span moment due to dead load

    =100.08 x 3.42 x 3.42/8 = 146.32

    Mid span moment due to live load

    = 4.52 x 3.42 x 3.42/8 = 6.61

    Total Mid Span Moment =152.93 kN.m

    3.2 Bottom Slab

    Fixed end moment due to dead load

    =115.83 x 3.42 x 3.42/12 = 112.9 Fixed end moment due to live load = 4.41

    Total xed end moment = 117.31 kN.m

    Mid span moment due to dead load

    = 115.83 x 3.42 x 3.42/8 = 169.35

    Mid span moment due to live load = 6.61

    Total Mid Span Moment = 175.96 kN.m

    3.3 Side Wall

    3.3.1Case 1 : Box empty, surcharge load on side ll

    F.E.M at top due to dead load

    =45 x 3.42 x 3.42/12 +30.78 x 3.42 x 3.42/30 = 55.86

    F.E.M at top due to live load= 10.8 x 3.42 x 3.42/12 = 10.53

    Total F.E.M at top = 66.39 kN.m

    F.E.M at base due to dead load

    = 43.86+30.78 x 3.42 x 3.42/20 = 61.86 kN.m

    F.E.M at base due to live load = 10.53

    Total F.E.M at base = 72.39 kN.m

    Mid span moment due to dead load

    = 45 x 3.42 x 3.42/8+30.78 x 3.42 x 3.42/16 = 88.29

    Fig. 4 Force Diagram for wall (All dimensions are in m)

    Pressure due to submerged earth =13.68 kN/m

    Pressure due to earth surcharge = 45 kN/m

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    Mid span moment due to live load= 10.8 x 3.42 x 3.42/8 = 15.79

    Total Mid Span Moment =104.08 kN.m

    3.3.2 Case 2 : Box full, live load surcharge on side ll.

    F.E.M at top due to dead load= 43.86+13.68 x 3.42 x 3.42/30 = 49.19

    F.E.M at top due to live load = 10.53

    Total F.E.M at top = 59.72 kN.m

    F.E.M at base due to dead load= 43.86+13.68 x 3.42 x 3.42/20 = 51.86

    F.E.M at base due to live load = 10.53

    Total F.E.M at bottom = 62.39 kN.m

    Mid span moment due to dead load= 65.79+13.68 x 3.42 x 3.42/16 = 75.79

    Mid span moment due to live load = 15.79

    Total Mid Span Moment = 91.58 kN.m3.3.3 Case 3 : Box full, no live load surcharge

    F.E.M at top due to dead load= 43.86 + 5.33 = 49.19 kN.m

    F.E.M due to live load = 0

    Total F.E.M at top = 49.19

    F.E.M at base due to dead load= 43.86 + 8 = 51.86

    F.E.M at base due to live load = 0

    Total F.E.M at base = 51.86 kN.m

    Mid span moment due to dead load

    = 65.79 + 13.68 x 3.42 x 3.42/16 = 75.79 Mid span moment due to live load = 0

    Total Mid Span Moment = 75.79 kN.m

    4 DISTRIBUTION FACTORS ARE SAME

    AS OBTAINED FOR BOX WITHOUT

    CUSHION

    5 MOMENT DISTRIBUTION

    5.1 F.E.M Due to Dead Load MAB= MBA = 97.54 kN.m

    MDC= MCD = 112.90 kN.m

    MAD= MBC = 55.86 kN.m (case 1),

    49.19 kN.m (case 2), 49.19 kN.m (case 3)

    MDA= MCB = 61.86 kN.m (case 1),

    51.86 kN.m (case 2), 51.86 kN.m (case 3)

    5.2 F.E.M Due to Live Load

    MAB= MBA = 4.41 kN.m

    MDC= MCD = 4.41 kN.m

    MAD= MBC = 10.53 kN.m (case 1),

    10.53 kN.m(case 2), 0 (case 3)

    MDA= MCB = 10.53 kN.m (case 1),

    0.53 kN.m (case 2), 0 (case 3)

    5.3 F.E.M Due to Total Load

    MAB= MBA = 101.95 kN.m

    MDC= MCD = 117.31 kN.m

    MAD= MBC = 66.39 kN.m (case 1),

    59.72 kN.m(case 2), 49.19 kN.m (case 3)

    MDA= MCB = 72.39 kN.m (case 1),

    62.39 kN.m (case 2), 51.86 kN.m (case 3)

    A typical distribution is shown in Table 1. Results basedon similar distribution for other combination of loads

    were done and given in Table 2.

    Table 1 Moment Distribution for Total Load on Top & Bottom Slab and Case 1 Load on Walls

    Joint A B C D

    Member AB AD BA BC CB CD DC DA

    D.F 0.500 0.500 0.500 0.500 0.500 0.500 0.500 0.500

    F.E.M -101.955 66.39 101.955 -66.389 72.389 -117.307 117.307 -72.389

    DIST. 17.78 17.78 -17.78 -17.78 22.46 22.46 -22.46 -22.46

    C.O. -8.89 -11.23 8.892 11.229 -8.892 -11.229 11.229 8.892

    DIST. 10.06 10.06 -10.06 -10.06 10.06 10.06 -10.06 -10.06

    C.O. -5.03 -5.03 5.030 5.030 -5.030 -5.030 5.030 5.030

    DIST. 5.03 5.03 -5.03 -5.03 5.03 5.03 -5.03 -5.03

    C.O. -2.52 -2.52 2.515 2.515 -2.515 -2.515 2.515 2.515

    DIST. 2.52 2.52 -2.52 -2.52 2.52 2.52 -2.52 -2.52

    C.O. -1.26 -1.26 1.258 1.258 -1.258 -1.258 1.258 1.258

    DIST. 1.26 1.26 -1.26 -1.26 1.26 1.26 -1.26 -1.26

    FINAL -83.00 83.00 83.00 -83.00 96.02 -96.02 96.02 -96.02

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    Table 2 Support Moments

    Load

    Distributed Moments at Supports

    RemarksCase

    MAB MDC MAD MDA

    (MBA) (MCD) (MBC) (MCB)

    Dead Load

    (1) (-) 75.54 88.55 75.54 (-) 88.55

    Load on top slab and bottom

    slab remains same in all

    cases, only load on side wall

    varies.

    No braking force need be

    considered due to cushion.

    (2) (-) 71.79 83.97 71.79 (-) 83.97

    (3) (-) 71.79 83.97 71.79 (-) 83.97

    Live Load

    (1) (-) 7.47 7.47 7.47 (-) 7.47

    (2) (-) 7.47 7.47 7.47 (-) 7.47

    (3) (-) 2.20 2.20 2.20 (-) 2.20

    Total Load

    (1) (-) 83.00 96.02 83.00 (-) 96.02

    (2) (-) 79.25 91.43 79.25 (-)91.43

    (3) (-) 73.99 86.17 73.99 (-) 86.17

    Maximum All cases 83.00 96.02 83.00 96.02

    Table 3 Mid Span Moments

    Member Case 1 Case 2 Case 3 Remarks

    MAB

    152.93 - 83.0 = 69.93 152.93 - 79.25 = 73.68 152.93 - 73.99 = 78.94When surcharge is not

    taken the Wall bends

    outwardly.

    MDC

    175.96 - 96.02 = 79.94 175.96 - 91.43 = 84.53 175.96 - 86.17 = 89.79

    MAD

    104.08 - (83+96.02)/2

    = 14.57

    91.58 - (79.25+91.43)/2

    = 6.24

    75.79 - (73.99+86.17)/2

    = (-) 4.29

    6 DESIGN OF SECTION

    Table 4 Moment and Reinforcement at Salient Section

    Member MAB MDCMid span

    AB DC AD

    Moment in kN.m 83.0 96.02 78.94 89.79 14.57

    Area of steel in mm 1271 1579 1209 1477 223

    6.1 Top Slab

    Maximum moment support/mid span = 83.0 kN.m

    Depth required =

    Check for Shear

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    Provide shear reinforcement

    Shear capacity

    = 0.2623 x 1000 x 362 = 94953N = 94.95 kN

    Balance Shear = 113.80 94.95 = 18.85 kN

    Take spacing 250 c/c of 8 mm

    Shear capacity of section

    = 0.2623 x 362 = 94.95kN

    Say x is the distance from the face of wall where

    shear force equals shear capacity of the section.

    Then,

    and x = 0.543 m, say 600 mm

    Provide shear reinforcement upto 600 mm from

    face of near wall on both sides.

    6.2 Bottom Slab

    Maximum Moment support/mid span = 96.02 kN.m

    Provided = 420 75 8 = 337 mm is o.k.

    Check for Shear

    Shear Stress = 0.3975 N/mm

    Provide shear reinforcements

    Shear Capacity

    = 0.299 x 337 x 1000 = 100763 N =100.76 kN

    Balance shear force

    = 133.95 100.760 =33.19 kN

    x is the distance from face of wall where shear

    force equals shear capacity of the section

    Then,

    and x = 0.613 m say 650 mm

    Provide shear reinforcement upto 650 mm from

    face of near wall on both sides.

    6.3 Side Walls

    Maximum moments at junctions of slabs and

    walls are same as slabs. Hence provide same

    reinforcements as slabs at junctions/supports.

    Check for Shear

    Maximum shear near top at deff

    from top slab is

    obtained as under :

    Fig. 6 Shear force at dig. (All dimensions are in m)

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    ANNEX C

    (Para 9)

    RCC BOX CULVERT, DESIGNATION: [1/3 x 3/5]

    STAAD. Pro : Structural Analysis and Design Software

    STAAD SPACE

    START JOB INFORMATION

    ENGINEER DATE 17-Dec-08

    END JOB INFORMATION

    INPUT WIDTH 79

    * ANALYSIS FOR LIVE LOAD

    *

    *BOTTOM SLAB

    *LONGITUDINAL MEMBER

    * TRANSVERSE MEMBER

    *TOP SLAB*LONGITUDINAL MEMBER

    * TRANSVERSE MEMBER

    * VERTICAL WALL

    *

    UNIT METER kN

    JOINT COORDINATES

    1 0 0 0; 2 0 0 1.6416; 3 0 0 3.284; 4 0 0 4.926; 5 0 0 6.568; 6 0 0 8.21;

    7 0 0 9.852; 8 0 0 11.494; 9 0 0 13.136; 10 0 0 14.778; 11 0 0 16.42;

    12 0 0 18.062; 13 0 0 19.704; 14 0.57 0 0; 15 0.57 0 1.6416; 16 0.57 0 3.284;

    17 0.57 0 4.926; 18 0.57 0 6.568; 19 0.57 0 8.21; 20 0.57 0 9.852;

    21 0.57 0 11.494; 22 0.57 0 13.136; 23 0.57 0 14.778; 24 0.57 0 16.42;25 0.57 0 18.062; 26 0.57 0 19.704; 27 1.14 0 0; 28 1.14 0 1.6416;

    29 1.14 0 3.284; 30 1.14 0 4.926; 31 1.14 0 6.568; 32 1.14 0 8.21;

    33 1.14 0 9.852; 34 1.14 0 11.494; 35 1.14 0 13.136; 36 1.14 0 14.778;

    37 1.14 0 16.42; 38 1.14 0 18.062; 39 1.14 0 19.704; 40 1.71 0 0;

    41 1.71 0 1.6416; 42 1.71 0 3.284; 43 1.71 0 4.926; 44 1.71 0 6.568;

    45 1.71 0 8.21; 46 1.71 0 9.852; 47 1.71 0 11.494; 48 1.71 0 13.136;

    49 1.71 0 14.778; 50 1.71 0 16.42; 51 1.71 0 18.062; 52 1.71 0 19.704;

    53 2.28 0 0; 54 2.28 0 1.6416; 55 2.28 0 3.284; 56 2.28 0 4.926;

    57 2.28 0 6.568; 58 2.28 0 8.21; 59 2.28 0 9.852; 60 2.28 0 11.494;

    61 2.28 0 13.136; 62 2.28 0 14.778; 63 2.28 0 16.42; 64 2.28 0 18.062;

    65 2.28 0 19.704; 66 2.85 0 0; 67 2.85 0 1.6416; 68 2.85 0 3.284;69 2.85 0 4.926; 70 2.85 0 6.568; 71 2.85 0 8.21; 72 2.85 0 9.852;

    73 2.85 0 11.494; 74 2.85 0 13.136; 75 2.85 0 14.778; 76 2.85 0 16.42;

    77 2.85 0 18.062; 78 2.85 0 19.704; 79 3.42 0 0; 80 3.42 0 1.6416;

    81 3.42 0 3.284; 82 3.42 0 4.926; 83 3.42 0 6.568; 84 3.42 0 8.21;

    85 3.42 0 9.852; 86 3.42 0 11.494; 87 3.42 0 13.136; 88 3.42 0 14.778;

    89 3.42 0 16.42; 90 3.42 0 18.062; 91 3.42 0 19.704; 92 0 3.42 0;

    93 0 3.42 1.6416; 94 0 3.42 3.284; 95 0 3.42 4.926; 96 0 3.42 6.568;

    97 0 3.42 8.21; 98 0 3.42 9.852; 99 0 3.42 11.494; 100 0 3.42 13.136;

    101 0 3.42 14.778; 102 0 3.42 16.42; 103 0 3.42 18.062; 104 0 3.42 19.704;

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    105 0.57 3.42 0; 106 0.57 3.42 1.6416; 107 0.57 3.42 3.284;

    108 0.57 3.42 4.926; 109 0.57 3.42 6.568; 110 0.57 3.42 8.21;

    111 0.57 3.42 9.852; 112 0.57 3.42 11.494; 113 0.57 3.42 13.136;

    114 0.57 3.42 14.778; 115 0.57 3.42 16.42; 116 0.57 3.42 18.062;

    117 0.57 3.42 19.704; 118 1.14 3.42 0; 119 1.14 3.42 1.6416;

    120 1.14 3.42 3.284; 121 1.14 3.42 4.926; 122 1.14 3.42 6.568;

    123 1.14 3.42 8.21; 124 1.14 3.42 9.852; 125 1.14 3.42 11.494;

    126 1.14 3.42 13.136; 127 1.14 3.42 14.778; 128 1.14 3.42 16.42;

    129 1.14 3.42 18.062; 130 1.14 3.42 19.704; 131 1.71 3.42 0;

    132 1.71 3.42 1.6416; 133 1.71 3.42 3.284; 134 1.71 3.42 4.926;

    135 1.71 3.42 6.568; 136 1.71 3.42 8.21; 137 1.71 3.42 9.852;

    138 1.71 3.42 11.494; 139 1.71 3.42 13.136; 140 1.71 3.42 14.778;

    141 1.71 3.42 16.42; 142 1.71 3.42 18.062; 143 1.71 3.42 19.704;

    144 2.28 3.42 0; 145 2.28 3.42 1.6416; 146 2.28 3.42 3.284;

    147 2.28 3.42 4.926; 148 2.28 3.42 6.568; 149 2.28 3.42 8.21;

    150 2.28 3.42 9.852; 151 2.28 3.42 11.494; 152 2.28 3.42 13.136;

    153 2.28 3.42 14.778; 154 2.28 3.42 16.42; 155 2.28 3.42 18.062;

    156 2.28 3.42 19.704; 157 2.85 3.42 0; 158 2.85 3.42 1.6416;

    159 2.85 3.42 3.284; 160 2.85 3.42 4.926; 161 2.85 3.42 6.568;

    162 2.85 3.42 8.21; 163 2.85 3.42 9.852; 164 2.85 3.42 11.494;

    165 2.85 3.42 13.136; 166 2.85 3.42 14.778; 167 2.85 3.42 16.42;

    168 2.85 3.42 18.062; 169 2.85 3.42 19.704; 170 3.42 3.42 0;

    171 3.42 3.42 1.6416; 172 3.42 3.42 3.284; 173 3.42 3.42 4.926;

    174 3.42 3.42 6.568; 175 3.42 3.42 8.21; 176 3.42 3.42 9.852;

    177 3.42 3.42 11.494; 178 3.42 3.42 13.136; 179 3.42 3.42 14.778;

    180 3.42 3.42 16.42; 181 3.42 3.42 18.062; 182 3.42 3.42 19.704; 183 0 0.855 0;

    184 0 0.855 1.6416; 185 0 0.855 3.284; 186 0 0.855 4.926; 187 0 0.855 6.568;

    188 0 0.855 8.21; 189 0 0.855 9.852; 190 0 0.855 11.494; 191 0 0.855 13.136;192 0 0.855 14.778; 193 0 0.855 16.42; 194 0 0.855 18.062; 195 0 0.855 19.704;

    196 3.42 0.855 0; 197 3.42 0.855 1.6416; 198 3.42 0.855 3.284;

    199 3.42 0.855 4.926; 200 3.42 0.855 6.568; 201 3.42 0.855 8.21;

    202 3.42 0.855 9.852; 203 3.42 0.855 11.494; 204 3.42 0.855 13.136;

    205 3.42 0.855 14.778; 206 3.42 0.855 16.42; 207 3.42 0.855 18.062;

    208 3.42 0.855 19.704; 209 0 1.71 0; 210 0 1.71 1.6416; 211 0 1.71 3.284;

    212 0 1.71 4.926; 213 0 1.71 6.568; 214 0 1.71 8.21; 215 0 1.71 9.852;

    216 0 1.71 11.494; 217 0 1.71 13.136; 218 0 1.71 14.778; 219 0 1.71 16.42;

    220 0 1.71 18.062; 221 0 1.71 19.704; 222 3.42 1.71 0; 223 3.42 1.71 1.6416;

    224 3.42 1.71 3.284; 225 3.42 1.71 4.926; 226 3.42 1.71 6.568;

    227 3.42 1.71 8.21; 228 3.42 1.71 9.852; 229 3.42 1.71 11.494;230 3.42 1.71 13.136; 231 3.42 1.71 14.778; 232 3.42 1.71 16.42;

    233 3.42 1.71 18.062; 234 3.42 1.71 19.704; 235 0 2.565 0; 236 0 2.565 1.6416;

    237 0 2.565 3.284; 238 0 2.565 4.926; 239 0 2.565 6.568; 240 0 2.565 8.21;

    241 0 2.565 9.852; 242 0 2.565 11.494; 243 0 2.565 13.136; 244 0 2.565 14.778;

    245 0 2.565 16.42; 246 0 2.565 18.062; 247 0 2.565 19.704; 248 3.42 2.565 0;

    249 3.42 2.565 1.6416; 250 3.42 2.565 3.284; 251 3.42 2.565 4.926;

    252 3.42 2.565 6.568; 253 3.42 2.565 8.21; 254 3.42 2.565 9.852;

    255 3.42 2.565 11.494; 256 3.42 2.565 13.136; 257 3.42 2.565 14.778;

    258 3.42 2.565 16.42; 259 3.42 2.565 18.062; 260 3.42 2.565 19.704;

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    MEMBER INCIDENCES

    1 1 2; 2 2 3; 3 3 4; 4 4 5; 5 5 6; 6 6 7; 7 7 8; 8 8 9; 9 9 10; 10 10 11;

    11 11 12; 12 12 13; 13 14 15; 14 15 16; 15 16 17; 16 17 18; 17 18 19; 18 19 20;

    19 20 21; 20 21 22; 21 22 23; 22 23 24; 23 24 25; 24 25 26; 25 27 28; 26 28 29;

    27 29 30; 28 30 31; 29 31 32; 30 32 33; 31 33 34; 32 34 35; 33 35 36; 34 36 37;

    35 37 38; 36 38 39; 37 40 41; 38 41 42; 39 42 43; 40 43 44; 41 44 45; 42 45 46;43 46 47; 44 47 48; 45 48 49; 46 49 50; 47 50 51; 48 51 52; 49 53 54; 50 54 55;

    51 55 56; 52 56 57; 53 57 58; 54 58 59; 55 59 60; 56 60 61; 57 61 62; 58 62 63;

    59 63 64; 60 64 65; 61 66 67; 62 67 68; 63 68 69; 64 69 70; 65 70 71; 66 71 72;

    67 72 73; 68 73 74; 69 74 75; 70 75 76; 71 76 77; 72 77 78; 73 79 80; 74 80 81;

    75 81 82; 76 82 83; 77 83 84; 78 84 85; 79 85 86; 80 86 87; 81 87 88; 82 88 89;

    83 89 90; 84 90 91; 85 1 14; 86 14 27; 87 27 40; 88 40 53; 89 53 66; 90 66 79;

    91 2 15; 92 15 28; 93 28 41; 94 41 54; 95 54 67; 96 67 80; 97 3 16; 98 16 29;

    99 29 42; 100 42 55; 101 55 68; 102 68 81; 103 4 17; 104 17 30; 105 30 43;

    106 43 56; 107 56 69; 108 69 82; 109 5 18; 110 18 31; 111 31 44; 112 44 57;

    113 57 70; 114 70 83; 115 6 19; 116 19 32; 117 32 45; 118 45 58; 119 58 71;

    120 71 84; 121 7 20; 122 20 33; 123 33 46; 124 46 59; 125 59 72; 126 72 85;

    127 8 21; 128 21 34; 129 34 47; 130 47 60; 131 60 73; 132 73 86; 133 9 22;

    134 22 35; 135 35 48; 136 48 61; 137 61 74; 138 74 87; 139 10 23; 140 23 36;

    141 36 49; 142 49 62; 143 62 75; 144 75 88; 145 11 24; 146 24 37; 147 37 50;

    148 50 63; 149 63 76; 150 76 89; 151 12 25; 152 25 38; 153 38 51; 154 51 64;

    155 64 77; 156 77 90; 157 13 26; 158 26 39; 159 39 52; 160 52 65; 161 65 78;

    162 78 91; 163 92 93; 164 93 94; 165 94 95; 166 95 96; 167 96 97; 168 97 98;

    169 98 99; 170 99 100; 171 100 101; 172 101 102; 173 102 103; 174 103 104;

    175 105 106; 176 106 107; 177 107 108; 178 108 109; 179 109 110; 180 110 111;

    181 111 112; 182 112 113; 183 113 114; 184 114 115; 185 115 116; 186 116 117;

    187 118 119; 188 119 120; 189 120 121; 190 121 122; 191 122 123; 192 123 124;

    193 124 125; 194 125 126; 195 126 127; 196 127 128; 197 128 129; 198 129 130;

    199 131 132; 200 132 133; 201 133 134; 202 134 135; 203 135 136; 204 136 137;205 137 138; 206 138 139; 207 139 140; 208 140 141; 209 141 142; 210 142 143;

    211 144 145; 212 145 146; 213 146 147; 214 147 148; 215 148 149; 216 149 150;

    217 150 151; 218 151 152; 219 152 153; 220 153 154; 221 154 155; 222 155 156;

    223 157 158; 224 158 159; 225 159 160; 226 160 161; 227 161 162; 228 162 163;

    229 163 164; 230 164 165; 231 165 166; 232 166 167; 233 167 168; 234 168 169;

    235 170 171; 236 171 172; 237 172 173; 238 173 174; 239 174 175; 240 175 176;

    241 176 177; 242 177 178; 243 178 179; 244 179 180; 245 180 181; 246 181 182;

    247 92 105; 248 105 118; 249 118 131; 250 131 144; 251 144 157; 252 157 170;

    253 93 106; 254 106 119; 255 119 132; 256 132 145; 257 145 158; 258 158 171;

    259 94 107; 260 107 120; 261 120 133; 262 133 146; 263 146 159; 264 159 172;

    265 95 108; 266 108 121; 267 121 134; 268 134 147; 269 147 160; 270 160 173;

    271 96 109; 272 109 122; 273 122 135; 274 135 148; 275 148 161; 276 161 174;277 97 110; 278 110 123; 279 123 136; 280 136 149; 281 149 162; 282 162 175;

    283 98 111; 284 111 124; 285 124 137; 286 137 150; 287 150 163; 288 163 176;

    289 99 112; 290 112 125; 291 125 138; 292 138 151; 293 151 164; 294 164 177;

    295 100 113; 296 113 126; 297 126 139; 298 139 152; 299 152 165; 300 165 178;

    301 101 114; 302 114 127; 303 127 140; 304 140 153; 305 153 166; 306 166 179;

    307 102 115; 308 115 128; 309 128 141; 310 141 154; 311 154 167; 312 167 180;

    313 103 116; 314 116 129; 315 129 142; 316 142 155; 317 155 168; 318 168 181;

    319 104 117; 320 117 130; 321 130 143; 322 143 156; 323 156 169; 324 169 182;

    325 183 184; 326 184 185; 327 185 186; 328 186 187; 329 187 188; 330 188 189;

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    331 189 190; 332 190 191; 333 191 192; 334 192 193; 335 193 194; 336 194 195;

    337 196 197; 338 197 198; 339 198 199; 340 199 200; 341 200 201; 342 201 202;

    343 202 203; 344 203 204; 345 204 205; 346 205 206; 347 206 207; 348 207 208;

    349 209 210; 350 210 211; 351 211 212; 352 212 213; 353 213 214; 354 214 215;

    355 215 216; 356 216 217; 357 217 218; 358 218 219; 359 219 220; 360 220 221;

    361 222 223; 362 223 224; 363 224 225; 364 225 226; 365 226 227; 366 227 228;367 228 229; 368 229 230; 369 230 231; 370 231 232; 371 232 233; 372 233 234;

    373 235 236; 374 236 237; 375 237 238; 376 238 239; 377 239 240; 378 240 241;

    379 241 242; 380 242 243; 381 243 244; 382 244 245; 383 245 246; 384 246 247;

    385 248 249; 386 249 250; 387 250 251; 388 251 252; 389 252 253; 390 253 254;

    391 254 255; 392 255 256; 393 256 257; 394 257 258; 395 258 259; 396 259 260;

    397 1 183; 398 183 209; 399 209 235; 400 235 92; 401 2 184; 402 184 210;

    403 210 236; 404 236 93; 405 3 185; 406 185 211; 407 211 237; 408 237 94;

    409 4 186; 410 186 212; 411 212 238; 412 238 95; 413 5 187; 414 187 213;

    415 213 239; 416 239 96; 417 6 188; 418 188 214; 419 214 240; 420 240 97;

    421 7 189; 422 189 215; 423 215 241; 424 241 98; 425 8 190; 426 190 216;

    427 216 242; 428 242 99; 429 9 191; 430 191 217; 431 217 243; 432 243 100;

    433 10 192; 434 192 218; 435 218 244; 436 244 101; 437 11 193; 438 193 219;

    439 219 245; 440 245 102; 441 12 194; 442 194 220; 443 220 246; 444 246 103;

    445 13 195; 446 195 221; 447 221 247; 448 247 104; 449 91 208; 450 208 234;

    451 234 260; 452 260 182; 453 90 207; 454 207 233; 455 233 259; 456 259 181;

    457 89 206; 458 206 232; 459 232 258; 460 258 180; 461 88 205; 462 205 231;

    463 231 257; 464 257 179; 465 87 204; 466 204 230; 467 230 256; 468 256 178;

    469 86 203; 470 203 229; 471 229 255; 472 255 177; 473 85 202; 474 202 228;

    475 228 254; 476 254 176; 477 84 201; 478 201 227; 479 227 253; 480 253 175;

    481 83 200; 482 200 226; 483 226 252; 484 252 174; 485 82 199; 486 199 225;

    487 225 251; 488 251 173; 489 81 198; 490 198 224; 491 224 250; 492 250 172;

    493 80 197; 494 197 223; 495 223 249; 496 249 171; 497 79 196; 498 196 222;

    499 222 248; 500 248 170;START GROUP DEFINITION

    MEMBER

    _TS 253 TO 318

    _TS1 247 TO 252 319 TO 324

    _BS 91 TO 156

    _BS1 85 TO 90 157 TO 162

    _DBS 1 TO 84 163 TO 246 325 TO 396

    END GROUP DEFINITION

    DEFINE MATERIAL START

    ISOTROPIC MATERIAL1

    E 3.05e+007POISSON 0.196183

    ISOTROPIC MATERIAL2

    E 3.05e+007

    POISSON 0.196183

    DENSITY 24

    END DEFINE MATERIAL

    MEMBER PROPERTY AMERICAN

    85 TO 90 157 TO 162 247 TO 252 319 TO 324 PRIS YD 0.42 ZD 0.821

    91 TO 156 253 TO 318 PRIS YD 0.42 ZD 1.642

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    401 TO 444 453 TO 496 PRIS YD 0.42 ZD 1.642

    1 TO 12 73 TO 84 163 TO 174 235 TO 246 PRIS YD 0.42 ZD 0.285

    13 TO 72 175 TO 234 PRIS YD 0.42 ZD 0.57

    397 TO 400 445 TO 452 497 TO 500 PRIS YD 0.42 ZD 0.821

    325 TO 396 PRIS YD 0.42 ZD 0.855

    CONSTANTS

    MATERIAL MATERIAL1 MEMB 1 TO 84 163 TO 246 325 TO 396

    MATERIAL MATERIAL2 MEMB 85 TO 162 247 TO 324 397 TO 500

    SUPPORTS

    1 TO 91 ELASTIC MAT DIRECT Y SUBGRADE 20400

    *DEFINE MOVING LOAD

    * IMPACT FACTOR 1

    * REDUCTION OF LOAD 20%

    *TYPE 1 LOAD 28 28 28 28 28 28 28 28 28 28

    *DIST 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46

    *TYPE 2 LOAD 28 28 28 28 28 28 28 28 28 28

    *DIST 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46*TYPE 3 LOAD 68 68 68 68 48 48 32

    *DIST 1.37 3.05 1.37 2.13 1.52 3.96

    *TYPE 4 LOAD 68 68 68 68 48 48 32

    *DIST 1.37 3.05 1.37 2.13 1.52 3.96

    *TYPE 5 LOAD 27 27 27 27 46 46 11 11

    *DIST 3 3 3 4.3 1.2 3.2 1.1

    *TYPE 6 LOAD 27 27 27 27 46 46 11 11

    *DIST 3 3 3 4.3 1.2 3.2 1.1

    LOAD 1

    MEMBER LOAD

    253 TO 318 UNI GY -16.55247 TO 252 319 TO 324 UNI GY -8.275

    *LOAD 2

    MEMBER LOAD

    253 TO 318 UNI GY -148

    247 TO 252 319 TO 324 UNI GY -74

    1 TO 12 73 TO 84 UNI GY -30.24

    *ACTIVE EARTH PRESSURE ON BOTH SIDE OF WALL

    * COEFFICIENT OF ACTIVE EARTH PRESSURE = KA=0.5

    * CALCULATION IS BASED ON 0.50x20xWxH

    * LOAD 3

    MEMBER LOAD

    400 448 TRAP GX 0 6.318

    399 447 TRAP GX 6.318 12.64

    398 446 TRAP GX 12.64 18.95

    397 445 TRAP GX 18.95 25.27

    404 408 412 416 420 424 428 432 436 440 444 TRAP GX 0 12.64

    403 407 411 415 419 423 427 431 435 439 443 TRAP GX 12.64 25.27

    402 406 410 414 418 422 426 430 434 438 442 TRAP GX 25.27 37.91

    401 405 409 413 417 421 425 429 433 437 441 TRAP GX 37.91 50.54

    452 500 TRAP GX -6.318 0 -6.318

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    451 499 TRAP GX -12.64 -6.318 -12.64

    450 498 TRAP GX -18.95 -12.64 -18.95

    449 497 TRAP GX -25.27 -18.95 -25.27

    456 460 464 468 472 476 480 484 488 492 496 TRAP GX 0 -12.64

    455 459 463 467 471 475 479 483 487 491 495 TRAP GX -12.64 -25.27

    454 458 462 466 470 474 478 482 486 490 494 TRAP GX -25.27 -37.91

    453 457 461 465 469 473 477 481 485 489 493 TRAP GX -37.91 -50.54

    * VALUE USED 0.50 x 18 x 1.20 x W

    * SURCHARGE LOAD

    MEMBER LOAD

    397 TO 400 445 TO 448 UNI GX 45.812

    449 TO 452 497 TO 500 UNI GX -45.812

    401 TO 444 UNI GX 91.62

    453 TO 496 UNI GX -91.62

    253 TO 318 UNI GY -7.42

    247 TO 252 319 TO 324 UNI GY -3.71

    PRINT SUPPORT INFORMATION

    *LOAD 4 MOVING LOAD

    *LOAD GENERATION 16 ADD LOAD 1

    *TYPE 1 0 3.42 12.12 XINC 0.5

    *TYPE 2 0 3.42 14.18 XINC 0.5

    *TYPE 1 0 3.42 16.22 XINC 0.5

    *TYPE 2 0 3.42 18.28 XINC 0.5

    *TYPE 5 0 3.42 20.15 XINC 0.5

    *TYPE 6 0 3.42 21.95 XINC 0.5

    *LOAD GENERATION 16 ADD LOAD 1

    *TYPE 1 0.5 8.42 12.12 XINC 0.5

    *TYPE 2 0.5 8.42 14.18 XINC 0.5

    *TYPE 1 0.5 8.42 16.22 XINC 0.5

    *TYPE 2 0.5 8.42 18.28 XINC 0.5

    *TYPE 5 0.5 8.42 20.15 XINC 0.5

    *TYPE 6 0.5 8.42 21.95 XINC 0.5

    *LOAD GENERATION 16 ADD LOAD 1

    *TYPE 1 1 8.42 12.12 XINC 0.5

    *TYPE 2 1 8.42 14.18 XINC 0.5

    *TYPE 1 1 8.42 16.22 XINC 0.5

    *TYPE 2 1 8.42 18.28 XINC 0.5

    *TYPE 5 1 8.42 20.15 XINC 0.5*TYPE 6 1 8.42 21.95 XINC 0.5

    *LOAD GENERATION 16 ADD LOAD 1

    *TYPE 1 1.5 8.42 12.12 XINC 0.5

    *TYPE 2 1.5 8.42 14.18 XINC 0.5

    *TYPE 1 1.5 8.42 16.22 XINC 0.5

    *TYPE 2 1.5 8.42 18.28 XINC 0.5

    *TYPE 5 1.5 8.42 20.15 XINC 0.5

    *TYPE 6 1.5 8.42 21.95 XINC 0.5

    *LOAD GENERATION 16 ADD LOAD 1

    *TYPE 1 2 8.42 12.12 XINC 0.5

    *TYPE 2 2 8.42 14.18 XINC 0.5

    *TYPE 1 2 8.42 16.22 XINC 0.5

    *TYPE 2 2 8.42 18.28 XINC 0.5

    *TYPE 5 2 8.42 20.15 XINC 0.5

    *TYPE 6 2 8.42 21.95 XINC 0.5

    *LOAD GENERATION 16 ADD LOAD 1

    *TYPE 1 2.5 8.42 12.12 XINC 0.5

    *TYPE 2 2.5 8.42 14.18 XINC 0.5*TYPE 1 2.5 8.42 16.22 XINC 0.5

    *TYPE 2 2.5 8.42 18.28 XINC 0.5

    *TYPE 5 2.5 8.42 20.15 XINC 0.5

    *TYPE 6 2.5 8.42 21.95 XINC 0.5

    *LOAD GENERATION 16 ADD LOAD 1

    *TYPE 1 3.995 8.42 12.12 XINC 0.5

    *TYPE 2 3.995 8.42 14.18 XINC 0.5

    *TYPE 1 3.995 8.42 16.22 XINC 0.5

    *TYPE 2 3.995 8.42 18.28 XINC 0.5

    *TYPE 5 6.01 8.42 20.15 XINC 0.5

    *TYPE 6 6.01 8.42 21.95 XINC 0.5

    * IMPACT FACTOR 1

    * REDUCTION OF LOAD 20%

    *TYPE 1 LOAD 28 28 28 28 28 28 28 28 28 28

    *DIST 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46

    *TYPE 2 LOAD 28 28 28 28 28 28 28 28 28 28

    *DIST 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46 0.46

    *TYPE 3 LOAD 68 68 68 68 48 48 32

    *DIST 1.37 3.05 1.37 2.13 1.52 3.96

    *TYPE 4 LOAD 68 68 68 68 48 48 32

    *DIST 1.37 3.05 1.37 2.13 1.52 3.96

    *TYPE 5 LOAD 27 27 27 27 46 46 11 11

    *DIST 3 3 3 4.3 1.2 3.2 1.1*TYPE 6 LOAD 27 27 27 27 46 46 11 11

    *DIST 3 3 3 4.3 1.2 3.2 1.1

    *LOAD 5 MOVING LOAD

    *LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 0 8.42 12.13 XINC 0.5

    *TYPE 4 0 8.42 14.06 XINC 0.5

    *TYPE 3 0 8.42 16.12 XINC 0.5

    *TYPE 4 0 8.42 18.08 XINC 0.5

    *TYPE 5 0 8.42 19.93 XINC 0.5

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    *TYPE 6 0 8.42 21.73 XINC 0.5

    *LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 0.5 8.42 12.63 XINC 0.5

    *TYPE 4 0.5 8.42 14.56 XINC 0.5

    *TYPE 3 0.5 8.42 16.62 XINC 0.5

    *TYPE 4 0.5 8.42 18.58 XINC 0.5

    *TYPE 5 0.5 8.42 20.43 XINC 0.5

    *TYPE 6 0.5 8.42 22.23 XINC 0.5

    *LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 1 8.42 12.63 XINC 0.5

    *TYPE 4 1 8.42 14.56 XINC 0.5

    *TYPE 3 1 8.42 16.62 XINC 0.5

    *TYPE 4 1 8.42 18.58 XINC 0.5

    *TYPE 5 1 8.42 20.43 XINC 0.5

    *TYPE 6 1 8.42 22.23 XINC 0.5

    *LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 1.5 8.42 12.63 XINC 0.5*TYPE 4 1.5 8.42 14.56 XINC 0.5

    *TYPE 3 1.5 8.42 16.62 XINC 0.5

    *TYPE 4 1.5 8.42 18.58 XINC 0.5

    *TYPE 5 1.5 8.42 20.43 XINC 0.5

    *TYPE 6 1.5 8.42 22.23 XINC 0.5

    *LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 2.395 8.42 12.63 XINC 0.5

    *TYPE 4 2.395 8.42 14.56 XINC 0.5

    *TYPE 3 2.395 8.42 16.62 XINC 0.5

    *TYPE 4 2.395 8.42 18.58 XINC 0.5

    *TYPE 5 6.01 8.42 20.43 XINC 0.5

    *TYPE 6 6.01 8.42 22.23 XINC 0.5*LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 3 8.42 12.63 XINC 0.5

    *TYPE 4 3 8.42 14.56 XINC 0.5

    *TYPE 3 3 8.42 16.62 XINC 0.5

    *TYPE 4 3 8.42 18.58 XINC 0.5

    *TYPE 5 3 8.42 20.43 XINC 0.5

    *TYPE 6 3 8.42 22.23 XINC 0.5

    *LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 3.5 8.42 12.63 XINC 0.5

    *TYPE 4 3.5 8.42 14.56 XINC 0.5

    *TYPE 3 3.5 8.42 16.62 XINC 0.5*TYPE 4 3.5 8.42 18.58 XINC 0.5

    *TYPE 5 3.5 8.42 20.43 XINC 0.5

    *TYPE 6 3.5 8.42 22.23 XINC 0.5

    *LOAD GENERATION 33 ADD LOAD 1

    *TYPE 3 5 8.42 12.63 XINC 0.5

    *TYPE 4 5 8.42 14.56 XINC 0.5

    *TYPE 3 5 8.42 16.62 XINC 0.5

    *TYPE 4 5 8.42 18.58 XINC 0.5

    *TYPE 5 5 8.42 20.43 XINC 0.5

    *TYPE 6 5 8.42 22.23 XINC 0.5

    * IMPACT FACTOR 1

    * REDUCTION OF LOAD 20%

    *TYPE 5 LOAD 27 27 27 27 46 46 11 11

    *DIST 3 3 3 4.3 1.2 3.2 1.1

    *TYPE 6 LOAD 27 27 27 27 46 46 11 11

    *DIST 3 3 3 4.3 1.2 3.2 1.1

    *LOAD 1 MOVING LOAD

    *LOAD GENERATION 44 ADD LOAD 1

    *TYPE 5 0 8.42 20.43 XINC 0.5

    *TYPE 6 0 8.42 22.23 XINC 0.5

    *TYPE 5 0 8.42 20.23 XINC 0.5

    *TYPE 6 0 8.42 22.23 XINC 0.5

    *TYPE 5 0 8.42 20.23 XINC 0.5

    *TYPE 6 0 8.42 22.23 XINC 0.5

    *TYPE 5 0 8.42 20.23 XINC 0.5

    *TYPE 6 0 8.42 22.23 XINC 0.5*TYPE 5 0 8.42 20.23 XINC 0.5

    *TYPE 6 0 8.42 22.23 XINC 0.5

    *LOAD GENERATION 44 ADD LOAD 1

    *TYPE 5 1.5 8.42 20.43 XINC 0.5

    *TYPE 6 1.5 8.42 22.23 XINC 0.5

    *TYPE 5 1.5 8.42 20.43 XINC 0.5

    *TYPE 6 1.5 8.42 22.23 XINC 0.5

    *TYPE 5 1.5 8.42 20.43 XINC 0.5

    *TYPE 6 1.5 8.42 22.23 XINC 0.5

    *TYPE 5 1.5 8.42 20.43 XINC 0.5

    *TYPE 6 1.5 8.42 22.23 XINC 0.5

    *TYPE 5 1.5 8.42 20.43 XINC 0.5*TYPE 6 1.5 8.42 22.23 XINC 0.5

    *LOAD GENERATION 44 ADD LOAD 1

    *TYPE 5 6.01 8.42 20.43 XINC 0.5

    *TYPE 6 6.01 8.42 22.23 XINC 0.5

    *TYPE 5 6.01 8.42 20.43 XINC 0.5

    *TYPE 6 6.01 8.42 22.23 XINC 0.5

    *TYPE 5 6.01 8.42 20.43 XINC 0.5

    *TYPE 6 6.01 8.42 22.23 XINC 0.5

    *TYPE 5 6.01 8.42 20.43 XINC 0.5

    *TYPE 6 6.01 8.42 22.23 XINC 0.5

    *TYPE 5 6.01 8.42 20.43 XINC 0.5*TYPE 6 6.01 8.42 22.23 XINC 0.5

    *LOAD GENERATION 44 ADD LOAD 1

    *TYPE 5 7 8.42 20.43 XINC 0.5

    *TYPE 6 7 8.42 22.23 XINC 0.5

    *TYPE 5 7 8.42 20.43 XINC 0.5

    *TYPE 6 7 8.42 22.23 XINC 0.5

    *TYPE 5 7 8.42 20.43 XINC 0.5

    *TYPE 6 7 8.42 22.23 XINC 0.5

    *TYPE 5 7 8.42 20.43 XINC 0.5

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    *TYPE 6 7 8.42 22.23 XINC 0.5

    *TYPE 5 7 8.42 20.43 XINC 0.5

    *TYPE 6 7 8.42 22.23 XINC 0.5

    PERFORM ANALYSIS

    PRINT SUPPORT REACTION

    PERFORM ANALYSIS

    PRINT MAXFORCE ENVELOPE LIST 85 TO 162

    247 TO 324

    PRINT MAXFORCE ENVELOPE LIST 397 TO 500

    START CONCRETE DESIGN

    Fig. 1 Model of box showing nodes and members

    CODE INDIAN

    FC 25000 ALL

    CLEAR 0.05 MEMB 163 TO 500

    CLEAR 0.075 MEMB 1 TO 162

    FYMAIN 415000 ALL

    FYSEC 415000 ALL

    DESIGN BEAM 1 TO 500

    END CONCRETE DESIGN

    FINISH

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    Table 1 Beam End Force Summary

    Beam Node L/C Axial Shear Torsion Bending

    Fx (kN) Fy (kN) Fz (kN) Mx

    (kNm)

    My

    (kNm)

    Mz

    (kNm)

    Max Fx 473 1 1: 85 294.174 -217.946 0.004 0.000 -0.002 -155.240

    Min Fx 163 1 1: 92 -0.004 0.091 -0.025 -0.005 0.021 0.075

    Max Fy 283 1 1: 98 181.746 294.014 0.002 -0.001 -0.000 136.419

    Min Fy 264 1 1: 172 181.859 -294.142 -0.070 0.004 0.016 136.647

    Max Fz 397 1 1: 1 147.825 109.156 5.118 -0.007 -5.533 77.873

    Min Fz 445 1 1: 13 147.845 109.162 -5.131 0.009 5.543 77.880

    Max

    Mx

    162 1 1: 78 0.000 142.375 0.000 0.718 0.000 3.481

    Min Mx 90 1 1: 66 0.000 142.354 0.000 -0.724 0.000 3.477

    Max

    My

    445 1 1: 13 147.845 109.162 -5.131 0.009 5.543 77.880

    Min My 397 1 1: 1 147.825 109.156 5.118 -0.007 -5.533 77.873

    Max Mz 405 1 1: 3 293.940 218.072 -0.640 0.030 0.082 155.434

    Min Mz 97 1 1: 3 0.000 -284.032 0.000 0.056 0.000 -155.434

    Refer Fig. 2

    WIDTH OF MEMBERS 97 to 102,405 TO 408,489 TO 492,259 TO 264 = 1.642 m

    B.M. PER M RUN AT CORNERS OF TOP SLAB IN MEMBERS 259,264,408 AND 492 = 136.369/1.642 =

    83.05 kNm

    B.M. PER M RUN AT CORNERS OF BOTTOM SLAB IN MEMBERS 97, 102, 405 AND 489 =

    155.434/1.642=94.66 kNm

    B.M. PER M RUN AT MID POINT OF TOP SLAB AT JOINT OF MEMBERS 261 AND 262 = 114.918/1.642

    = 69.99 kNm

    B.M. PER M RUN AT MID POINT OF BOTTOM SLAB AT JOINT OF MEMBERS 99 AND 100 =

    134.148/1.642 = 81.70 kNm

    B.M. PER M RUN AT MID POINT OF SIDE SLAB AT JOINT OF MEMBERS 406-407 AND 490-491 =

    25/1.642 = 15.22 kNm

    Refer Fig. 3

    SHEAR FORCE DIAGRAM

    WIDTH OF MEMBERS 121 to 126,421 to 424,283 TO 288,473 TO 476 = 1.642 m

    S.F. PER M RUN AT EFFECTIVE DISTANCE 0.622 m FROM CENTER OF SUPPORT IN TOP SLAB IN

    MEMEBR 284=97.972*1.088/(1.642*.57) = 113.88 kN

    S.F. PER M RUN AT EFFECTIVE DISTANCE 0.597 m FROM CENTER OF SUPPORT IN BOTTOM

    SLAB IN MEMBER 122

    =168.253 /(1.642) = 102.46 kN

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    S.F. PER M RUN AT EFFECTIVE DISTANCE 0.622 m FROM CENTER OF SUPPORT IN SIDE SLAB IN

    MEMEBR 424 =98.004*1.088/(1.642*.855) = 75.95 kN

    S.F. PER M RUN AT EFFECTIVE DISTANCE 0.622 m FROM CENTER OF SUPPORT IN SIDE SLAB IN

    MEMEBR 421

    =101.89*1.088 (1.642*.855) = 78.96 kN

    Fig. 2 Bending Moment Diagram

    (Value are for element length of 1.642 m)

    Fig. 3 Shear Force Diagram

    (Value are for element length of 1.642 m)