Question Design of Concrete VSem Civil

(OBJECTIVE QUESTION)

DESIGN OF CONCRETE (UNIT-1) (OBJECTIVE QUESTION)

1) Factor of safety for

a) Steel should be based on its yield stress

b) Concrete should be based on its ultimate stress

c)both a and b

d) None of these

2) Prestressing losses in post-tensioned and pre-tensioned beams are respectively

a) 15% and 20%

b) 20% and 15%

C) 15% and 15%

d) 20% and 20%

3) I n symmetrically reinforced sections shrinkage stresses in concrete and steel are respectively

a) Compressive and tensile

b) Tensile and compressive

c) Both compressive

d) Both tensile

4) The theoretical failure load of the beam for attainment of limit state of collapse in flexure is

a) 23.7kn

b) 25.6kn c) 28.7kn

d) 31.6kn

5) The partial factor of safety for concrete as per IS:456-2000 is

a) 1.50

b) 1.15

c) 0.87

d) 0.446

6) What is the value of minimum reinforcement in a slab

a) 0.1%

b) 0.12%

c) 0.15%

d) 0.2%

7) What is the value of flexural strength of % M25 concrete

a) 4.0Mpa

b) 3.5Mpa

c) 3.0Mpa

4)1.75Mpa

8) What should be the minimum grade of reinforced concrete in and around sea cost construction?

a) M35

b) M30

c) M25

d) M20

9) Doubly reinforced beams are recommended when

a) Depth of the beam is restricted

b) Breadth of the beam is restricted

c) Both depth and breadth are restricted

d) Shear is high

10) The effective width flange of the beam is

a) 3000mm

b) 1900mm

c) 1600mm

d) 1500mm

11) Yield line theory results in

a) Elastic solution

b) Lower bound solution

c) Upper bound solution

d) Unique solution

12) Shear span is defined as the zone where

a) Bending moment is zero

b) Shear force is zero

c) Shear force is constant

d) Bending moment is constant

13) Deflection can be controlled by using appropriate

a) Aspect ratio

b) Modular ratio

c)span/depth ratio

d) water/cement ratio

14) In limit state approach spacing of main reinforcement controls primarily

a) Collapse

b) Cracking

c) Deflection

d) Durability

15) Drops are provided in flat slab to resist

a) Bending moment

b) Thrust

c) Shear

d) Torsion

16) In an RCC Beam side face reinforcement is provided if its depth exceeds

a) 300mm

b) 500mm

c) 700mm

d) 750mm

17) In a load balanced prestressed concrete beam under self load the cross-section is subjected to

a) Axial stress

b) Bending stress

c) Axial and bending stress

d) Axial and shear stress

18) A reinforced concrete slab is 75mm thick the maximum size of reinforcement bar can be used is

a) 12mm diameter

b) 10mm diameter

C) 8mm diameter

d) 6mm diameter

19) Maximum spacing of vertical reinforcement in RCC wall should not exceed

a) The thickness of wall

b) 1.5 times the thickness of wall

c) 2 times the thickness of wall

d)3 times the thickness of wall

20) Ratio of the diameter of reinforcing bars and the slab thickness is

a) 1/4

b) 1/5

c) 1/6

d) 1/8

ASSUMPTION IN LIMIT STATE DESIGN METHOD(UNIT 2)

1)Strength and quality of concrete depends on

a)aggregate shape

b)aggregate grading

c)surface area of the aggregate

d)all of these

2)The lower water cement ratio in concrete produces

a)more density

b)small creep and shrinkage

c)more bond

d)all of these

3)The entrained air in concrete

a)increase workability

b)decrease workability

c)increase strength

d)none of these

4)Separation of ingredients from concrete during transportation is called

a)Bleeding

b)Creep

c)Segregation

d)Shrinkage

5)For making impermeable concrete the process contains

a)through mixing

b)proper compaction

c)proper curing

d)all of these

6)After casting an ordinary cement concrete on drying

a)shrinks

b)expands

c)remains unchanged

d)can expand or shrink

7)Approximate ratio of strength of cement concrete at 3 months to that at 28 days of curing is

a)1.15

b)1.30

c)1.0

d)0.75

8)Workability of concrete can be improved by addition

a)Iron

b)Sodium

c)Zinc

d)Sulphur

9)Split strength of concrete can be determined by

a)Brazilion

b)Vicat apparatus

c)Cube test

d)Briquettes test

10)Workability of concrete can be improved by

a)more sand

b)more cement

c)more fine aggregate

d)fineness of coarse aggregate

11)Workability of concrete is directly proportional to

a)grading of the aggregate

b)time of transit

c)aggregate cement ratio

d)none of these

12)Approx ratio of the strength of the concrete of 7 days to that of 28 days

a)0.56

b)0.85

c)1.0

d)1.15

13)Durability of concrete is proportional to

a)sand content

b)water cement ratio

c)aggregate ratio

d)cement aggregate ratio

14)Poissons ratio for concrete ranges between

a)0.10-0.15

b)0.15-0.25

c)0.25-0.30

d)0.30-0.35

15)Fineness modulus of aggregate is between

1)2-3.5

2)3.5-5.0

c)5-6.0

d)6-7.5

16)If slump of concrete mix is 60 mm,then its workability is

1)low

2)medium

c)high

d)very high

17)If compaction factor is 0.95,then workability of concrete is

a)very low

b)low

c)medium

d)high

18)Size of the fine aggregate should not exceed

a)2.0

b)3.0

c)3.5

d)4.75

19)Total creep strain in concrete is directely proportional to

a)elastic strain

b)time of loading

c)duration of loading

d)moisture content

20)Expansion joints are provided if length of the concrete exceeds

a)20m

b)45m

c)60m

d)75m

BEHAVIOUR OF RC BEAM IN SHEAR (UNIT-3)

1) Prestressing losses in post-tensioned and pre-tensioned beams are respectively

a) 15% and 20%

b) 20% and 15%

C) 15% and 15%

d) 20% and 20%

2) I n symmetrically reinforced sections shrinkage stresses in concrete and steel are respectively

a) Compressive and tensile

b) Tensile and compressive

c) Both compressive

d) Both tensile

3)Bond strength between steel and concrete is due to

a)friction

b)adhesion

c)both friction and adhesion

d)none of these

4)The theoretical failure load of the beam for attainment

Of limit state of collapse in flexure is

a)23.7kn

b)25.6kn

c)28.7kn

d)31.6kn

5) )If compaction factor is 0.95,then workability of concrete is

a)very low

b)low

c)medium

d)high

6)Reduction coefficient of a reinforced concrete column with an effective length of 4.8m and size 250*300mm is

a)0.80

b)0.85

c)0.90

d)0.95

7) Fineness modulus of aggregate is between

1)2-3.5

2)3.5-5.0

c)5-6.0

d)6-7.5

8)Sum of nodal forces at any yield line intersection in a slab is

a)zero

b)infinity

c)independent of the reinforcement

d)indeterminate

9)If sea water will use for preparing concrete it

a)will cause efflorescence

b)may corrode the reinforcement

c)will cause dampness

d)all of these

10)With rise in temperature of atmospheric air,setting time of cement

a)increases

b)decreases

c)remains affected

d)none of these

11)Main object of compaction of concrete is

a)eliminate air holes

b)achieve maximum density

c)get intimate contact between concrete and embedded material

d)all of these

12) Strength and quality of concrete depends on

a)aggregate shape

b)aggregate grading


d)all of these


a)more density


c)more bond

d)all of these




c)increase strength

d)decrease strength

15)Too wet concrete may cause

a)segregation

b)lower density

c)weakness of concrete

d)all of these

16)Minimum water cement ratio required for full hydration of cement is

a)0.18

b)0.36

c)0.54

d)0.60

17)Steam curing is not used with

a)ordinary Portland cement

b)rapid hardening cement

c)high alumina cement

d)all of these

18)In case of hand mixing of concrete,extra cement is to be added

a)5%

b)10%

c)15%

d)20%

19)Two main basic materials are

a)lime stone and silica

b)lime and alumina

c)lime and clay

d)lime and chalk

20) ) Shear span is defined as the zone where





Design of one way and two way solid slabs (unit-4)

1)Maximum permissible unit of magnesia concentration in ordinary portland cement is

a)2%

b)4%

c)6%

d)8%

2)Normal consistency of Portland cement is about

a)50%

b)30%

c)25%

d)15%

3)When water is added to cement

a)heat is generated

b)heat is absorbed

c)chemical reaction is started

d)impurities is washed out

4) )Reduction coefficient of a reinforced concrete column with an effective length of 4.8m and size 250*300mm is

a)0.80

b)0.85

c)0.90

d)0.95

5) ) The effective width flange of the beam is

a) 3000mm

b) 1900mm

c) 1600mm

d) 1500mm

6) Yield line theory results in

a) Elastic solution

b) Lower bound solution

c) Upper bound solution

d) Unique solution

7) Shear span is defined as the zone where





8) Deflection can be controlled by using appropriate

a) Aspect ratio

b) Modular ratio

c)span/depth ratio

d) water/cement ratio

9) In limit state approach spacing of main reinforcement controls primarily

a) Collapse

b) Cracking

c) Deflection

d) Durability

10)Percentage void ration of cement is

a)50

b)40

c)30

d)20

11)In case of deep beam or in thin webbed R.C.C, members the first crack form is

a)flexural crack

b)diagonal crack due to compression

c)diagonal crack due to tension

d)shear crack


a)zero

b)infinity


d)indeterminate





d)all of these


a)increases

b)decreases

c)remains affected

d)none of these





d)all of these

16) Strength and quality of concrete depends on

a)aggregate shape

b)aggregate grading


d)all of these


a)more density


c)more bond

d)all of these




c)increase strength

d)decrease strength

19)Too wet concrete may cause

a)segregation

b)lower density

c)weakness of concrete

d)all of these

20)An axially loaded column is of 300*300mm size,Effective length of column is 3m.what is the minimum eccentricity of the axial load for the column

a)0

b)10

c)16

d)20

Design of Columns by Limit State Design Method(Unit-5)

1)Flash set of Portland cement is

a)hardening of silicate content

b)flash hardening of calcium

c)flash hardening of gypsum

d)reaction of tricalcium aluminate with water

2)Fineness of cement is tested by

a)Le-chatelier apparatus

b)Sieve-analysis

c)Vicat,s needle

d)Specific surface air permeability method

3)Soundness test of cement is indicated by its soundness gives unsoundness due to

a)free lime only

b)magnesium only

c)both a and b

d)none of these

4)Maximum permissible unit of magnesia concentration in ordinary Portland cement is

a)2%

b)4%

c)6%

d)8%

5)Specific gravity of portland cement is

a)3.50

b)3.30

c)3.15

d)3.00

6)Density of Portland cement is about

a)25000

b)23000

c)20000

d)18000

7)Bulking of aggregate is due to

a)moisture content

b)absorbed water

c)voids

d)less compaction

8)If angularity number of a aggregate is increased then workability of concrete will

a)increase

b)decrease

c)no change

d)none of these

9)Sieve number used in the fineness modulus test of cement is

a)1

b)5

c)7

d)9

10)The theoretical failure load of the beam for attainment

Of limit state of collapse in flexure is

a)23.7kn

b)25.6kn

c)28.7kn

d)31.6kn

11 )If compaction factor is 0.95,then workability of concrete is

a)very low

b)low

c)medium

d)high

12)Reduction coefficient of a reinforced concrete column with an effective length of 4.8m and size 250*300mm is

a)0.80

b)0.85

c)0.90

d)0.95

13) Fineness modulus of aggregate is between

1)2-3.5

2)3.5-5.0

c)5-6.0

d)6-7.5


a)zero

b)infinity


d)indeterminate





d)all of these


a)increases

b)decreases

c)remains affected

d)none of these





d)all of these

18)For R.C.C section with congested reinforcement compaction factor is

a)0.8

b)0.87

c)0.92

d)0.95

19)Relation between strength of concrete (s) in kg/m3and get space ratio(x) is given by

a)S=600x

b)S=1200x2

c)S=2400x3

d)none of these

20)Strength of concrete decreases

a)if w/c ratio is less than 0.38

b)if w/c ratio is less than 0.6

c)with entrapped air

d)if cement is increased

(Theory Question)

DESIGN OF CONCRETE (unit-1)

1) Write a note on requirements of good concrete.

2) What are the various types of cement

3) What precautions should be taken while storing cement for a long time?

4) What do you mean by specific surface of a sample of cement

5) What do you mean by consistency of a cement paste

6) Describe the Vicat apparatus

7) How do you determine the initial and final setting times of cement

8) How are aggregate classified

9) What do you mean by fineness modulus?

10) What do you mean by grade of concrete? What are the grades recommended by the I.S.code?

11) Describe the slump test for concrete. What are the slump requirements for various situations?

12) What do you mean by equivalent concrete area of a reinforced concrete member?

13) What are the basic assumptions in the analysis of reinforced concrete members?

14) A 300mm*300mm R.C. member reinforced with 2032mm square of steel supports an axial compression load of 750kn.calculate the stresses in concrete and steel. Take m=18

15) A 400mm*400mm R.C. member has to support an axial compressive load of 425kn.if the stress in concrete is not to exceed 4N/mm square. Calculate the area of steel required. Take m=18

16) Describe about compacting factor test.

17) Describe about workability of concrete.

18) Describe about buckling of sand.

19) The cross section of a singly reinforced concrete beam is 300mm wide and 500mm deep to the centre of the tension reinforcement which consists of four bars of 16mm diameter. if the stresses in concrete and steel are not to exceed 7N/mm2and 140N/mm2respectively. Determine the moment of resistance of the beam. Take m=13.33

20)Find the percentage of tensile reinforcement necessary for a singly reinforced balanced rectangular section if the permissible stresses in concrete and steel are c and t Newton/mm2respectively and the modular ratio is m.

Design of concrete unit-2

1)A doubly reinforced rectangular beam is 300mm wide and 500mm deep to the centre of tension steel.it is reinforced with four bars of 18mm diameter as compressive steel at an effective cover of 40mm and with four bars of 20mm diameter as tensile steel.if the stresses in concrete and steel are not to the exceed 7n/mm2 and 230n/mm2 respectively,find the moment of resistance of the section.Take m=13.33 adopt revised elastic theory

2)A doubly reinforced rectangular beam is 300mm wide and 500mm deep to the centre of tension steel.it is reinforced with four bars of 20mm diameter as compressive steel at an effective cover of 40mm and with four bars of 25mm diameter as tensile steel.if the stresses in concrete and steel are not to the exceed 7n/mm2 and 230n/mm2 respectively,find the moment of resistance of the section.Take m=13.33 adopt revised elastic theory

3)A reinforced concrete section is subjected to a bending moment of 150KNm which may be positive or negative.if the permissible stresses in concrete and steel are 7N/mm2and 230N/mm2and m=13.33 .design the section




7)A doubly reinforced rectangular beam is 250mm wide and 550mm deep to the centre of tension steel.it is reinforced with four bars of 16mm diameter as compressive steel at an effective cover of 40mm and with four bars of 20mm diameter as tensile steel.if the stresses in concrete and steel are not to the

exceed 7n/mm2 and 230n/mm2 respectively,find the moment of resistance of the section.Take m=13.33 adopt revised elastic theory

8)A singly reinforced beam 250mm wide and 380mm deep to the centre of reinforcement is reinforced with 3 bars of 18mm diameter.Determine the depth of netural axis and the maximum stress in concrete when the stress in steel is 150N/mm2 .Take m=13.33

9)Find the permissible of tensile reinforcement necessary for a singly reinforced balanced rectangular section if the permissible stresses in concrete and steel are c and t Newton/mm2 respectively and the modular ratio is m.

10)Describe the analysis of a doubly reinforced section-conventional elastic theory

11)What are the effect of reinforcement in concrete

12)Describe about over reinforced section

13)Design a singly reinforced beam section subjected to a maximum bending moment of 55.35knm.The width of the beam may be made two third the effective depth.Use M20 anf Fe415 steel.

14)A singly reinforced beam 300mm wide and 450mm deep to the centre of reinforcement is reinforced with 4 bars of 16mm diameter.Determine the depth of netural axis and the maximum stress in concrete when the stress in steel is 150N/mm2 .Take m=13.33


16)Find the percentage of tensile reinforcement necessary for a singly reinforced balanced rectangular section if the permissible stresses in concrete and steel are c and t Newton/mm2respectively and the modular ratio is m.

17)Fine the moment of resistance of the beam section ,safe stresses in concrete and steel are 7N/mm2 and 230N/mm2 Take m=13.33

18)The beam section is subjected to a bending moment of 150kNm.Determine the maximum compressive stress in concrete and the tensile stress in steel .Take m=13.33

19)What are the properties of balanced sections for various grades of concrete with various types of steel.

20)What are the types of bars used in R.C.C

DESIGN OF CONCRETE (UNIT-3)

1)Describe about shear distribution in a beam of rectangular section

2)Describe about shear stresses in homogeneous sections

3)What are the design processes if vertical striuuups-conventional method

4)Abeam 200mm wide ,500mm effective depth and 6 metres span supports a total load of 190,500 Newtons including its weight.Find the maximum shear stress and determine the spacing of 10mm stirrups by conventional method,Allowable shear stress is 0.50N/mm2

5)Describe about lattice girder effect(Truss theory)

6) Whatis the revised theory recommended by the I.S.CODE?

7)A reinforced concrete section is subjected to a bending moment of 150KNm which may be positive or negative. if the permissible stresses in concrete and steel are 7N/mm2and 230N/mm2and m=13.33 .design the section

8) Whatare the recommendations development lengths?

9) Describe the necessity of bending reinforcement

10) Describe about Bond (Detailed examples with limit state design method)

11)A beam 300mm wide and 500mm effective deep of 5m span supports a total load of 20000N including its weight. Determine the maximum shear stress in concrete and the spacing of 10mm diameter stirrups by conventional method .Allowable shear stress is 0.50 N/mm2.Take c=7N/mm2.t=230N/mm2 ,a=0.90d.




15) Describe about shear distribution in a beam of rectangular section.

16) What are the concept of Equivalent Shear and Moments?

17) A reinforced rectangular beam of span 5m is 300mm wide and 550mm deep to the centre of the tensile reinforcement which consists of four bars of 22mm diameter .The beam carries a load of 20kn/m inclusive of its weight. Design the shear reinforcement. Use M20 concrete and Fe415 steel.




DESIGN OF CONCRETE (UNIT 4)

1)Discuss about reinforcement of a slab.

2)Discuss about loads on slabs.

3)What are the steps to be followed in the design of a one way slab.

4)Design a simply supported slab supported on masonary walls to the following requirements

a)Clear span=3m

b)Live load=4000N/m2

c)Use M20 concrete and Fe 415 steel

5)Discuss about slab carrying concentrated load.

6)Discuss about two way slabs(slabs spanning in two directions)

7)Discuss about Rankine-Grashoff Theory.

8)Discuss about Two way slabs with corners held down (Marcus correction)

9)Analysis of two way slabs by I.S.CODE

10)Design a slab over a room 4m*6m as per I.S.code.The edges of the slab are simply supported and the corners are not held down.The live load on the slab is 3000N/m2.The slab has a bearing of 150mm on the supporting walls.Use M20 concrete and Fe 415 steel.

11)Design a simply supported slab supported on masonary walls to the following requirements

a)Clear span=2.5m

b)Live load=3000N/m2

c)Use M20 concrete and Fe 415 steel

12)Discuss about disposition of reinforcement.

13)Design a 4m*6m interior panel of a two way continuous slab for a live load of 3000N/m2 .Use M20 concrete and Fe 415 steel.

14)Discuss about Flat slabs and what are the advantages of flat slab construction.

15)Discuss about Theory of a flat slab.

16)Discuss about bending moment of a flat slab

17)Discuss about Reinforcement in a flat slab.

18)Design an interior panel of a flat slab for a live load of 4000N/m2.The slab is provided with a floor finish weighing 1000 N/m2.The panels are 6m*6m.Drops shall be provided .Use M20 concrete and Fe415 steel.



DESIGN OF CONCRETE (UNIT 5)

1)Discuss about Transverse reinforcement.

2)What are recommendation regarding longitudinal reinforcement.

3)Discuss about Axially loaded short columns.

4)A short R.C.C columns 400mm*400mm is provide with 8 bars of 16mm diameter.If the effective length of the column is 2.25m.find the ultimate load for the column.Use M20 concrete and Fe 415 steel.

5)Find the area of steel required for a short reinforced concrete column 400mm*425mm to carry an axial load of 1195kn.Use M20 concrete and Fe 415 steel.

6)Analysis and design of axially loaded columns by the use of charts.

7)Determine the safe axial load for a short column 450mmm in diameter ,Reinforced with 6 bars of 25mm diameter.it is provided with 8mm diameter helical reinforcement at a high of 45mm.Use M20 concrete and Fe 415 steel

8)Discuss about combined axial load and uniaxial bending .

9)Areinforced concrete column section is 250mm*400mm is provided with reinforcement as given.Taking xu =550mm,find pu and MU .Use M15 concrete and Fe415 steel.

10)Discuss about Axial load and Biaxial Bending.

11)Design a short columns subjected to biaxial bending to the following particulars

a)Size of the column=400mm*400mm

b)Factored load=1200kn

c)Factored moment=85kn

d)Use M20 concrete and Fe415 steel

12) Describe about Bond (Detailed examples with limit state design method)



15)What are the properties of balanced sections for various grades of concrete with various types of steel.

16)What are the types of bars used in R.C.C

17)Describe the analysis of a doubly reinforced section-conventional elastic theory

18)What are the effect of reinforcement in concrete

19)Describe about over reinforced section

20)Determine the safe axial load for a short column 350mmm in diameter ,Reinforced with 8 bars of 20mm diameter.it is provided with 8mm diameter helical reinforcement at a high of 45mm.Use M20 concrete and Fe 415 steel

Question Design of Concrete VSem Civil

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