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EINSTEIN COLEGE OF ENGINEERING

CIVIL ENGINEERING DEPARTMENT

NOTES OF LESSIONS

SUBJECT NAME: CONSTRUCTION TECHNIQUES, EQUIPMENTS

AND PRACTICES

SUBJECT CODE: CE 36

YEAR&SEMESTER: II, III

OBJECTIVE:

The main objective of this course is to make the students aware of the various

construction techniques, practices and equipments needed for different types of

construction activities. At end this course students gain the knowledge about construction

procedures for sub and super structures and equipment needed for construction of various

types of structures from foundation to super structures.

UNIT-1

1. CONSTRUCTION PRACTICES 15 HRS

SPECIFICATION

1. General specification

2. Detailed specification

General specification

It give only general idea of the whole work and are useful in estimating the

approximate cost of construction .They give general description of the different part of

the building. This specification depends upon the types of building to be built.

Detailed specification

It gives details of each of the different types of work in the order in which the work is

carried out at the site.

DETAILS AND SEQUENCES OF ACTIVITIES

1. Site clearance

2. Marking

3. Earth work

4. Masonary

5. Flooring

6. Damp proofing courses

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Site clearance

a) Surface cleaning of grass, trees, and hillocks.

b) Cleaning of all obstruction on site

Marking

Marking is the setting out of building works

It consists of two operations.

a) setting out centre line

b) Setting out of trenches

.

Earth work

After setting out of trenches, we proceed with the excavation for the

foundation. The earthworks have been classified following.

a)soft or loose soil

b) Hard or dense soil

c) Ordinary rock not requiring blasting

d) Hard rock where blasting is allowed

e) Hard rock where blasting is not allowed

MASONRY

The masonry is a wall it built of individual blocks of material such as

stone, brick.concrete, hollow blocks, celluar concrete, laterite etc, usually in

horizontal courses cemented together some form of mortar.

1. Stone masonry

The construction are made by using stone blocks is called stone masonry.

Tools used in masonry

1.Trowel

2.Square

3.Plump rule

4.Spirit level

5.Line and pins

6.Bevel

7.Pick Axe

8.Crow Bar

Classification of masonry

a). Rubble masonry

b). Ashlars masonry

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a). Rubble masonry

In this category the stones used either undressed or rough dressed

having wider joint.

The following are the classication of rubble masonry

1. Uncoursed rubble masonry

2. Uncoursed random masonry

3. Uncoursed squared rubble

4. Coursed random rubble

5. Polymer rubble masonry

6. Ploygonal rubble masonry

7. Dry rubble masonry

b). Ashlars masonry

This is a costlier, high grade and superior quality of masonry. This is built

from accurately dressed stones with uniform and very fine joints of about 3mm

thickness.

The following are the classication of Ashlars masonry`

1. Ashlar fine masonry

2. Ashlar rough tooled

3. Ashlar rock

4. Ashlar chamfered

5. Ashlar facing

6. Ashlar block in course

2. Brick masonry The construction are made by using stone blocks is called brick masonry.

Tools used in masonry

1. Trowel

2. Square

3. Plump rule

4. Spirit level

5. Line and pins

6. Bloster

7. Brick Hammer

8. Scutch

The following are the classication of bonds in masonry

1. Stretcher bond

2. Header bond

3. English bond

4. Double Flemish bond

5. Single Flemish bond

6. Garden wall bond

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7. Facing bond

8. Dutch bond

9. Racking bond

3. Concrete hollow block masonry

The construction are made by using hollow blocks is called concrete

hollow block masonry.

The common size generally adopted for building blocks are:

1.39cm*19cm*30cm

2.39cm*19cm*20cm

3.39cm*19cm*10cm

FLOORING

Floors are the horizontal elements of a building structure which divide the

building into different levels for the purpose of creating more accommodation

with in a restricted space one above the other and provide support for the

occupants.

Types of flooring

1. Mud flooring

2 . Muram flooring

3. Stone flooring

4. Cement concrete flooring

5. Glass flooring

6. Marble flooring

7. Plastic flooring

Materials used

1. Wooden blocks

2. Stones

3. Bricks

4. Concrete

DAMP PROOFING COURCES

The damp proofing is a treatment of a building, against dampness.

Causes of dampness

1. Faulty design of structure,

2. Faulty construction

3. Use of poor quality materials in construction.

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Materials used for damp proofing

1. Flexible materials

2. Semi Rigid materials

3. Rigid materials

CONSTRACTION JOINTS

Joints provided in reinforcement concrete construction can be classified as

follows:

1. Construction joints

2. Expansion joints

3. Contraction joints

4. Sliding joints

Construction joints

These joints are provided at places where places of concrete has to be

stopped for some reasons during construction.

Expansion joints

This joints permit expansion and construction. They are provided to allow

for the movement of the structure and hence they come under the movement

joint.

Contraction joints

These joints allow only contraction. They generally consist of a simple butt

joint without any bond. They are shrinkage joints to allow shrinkage.

Sliding joints

These joints are usually formed by introducing smooth layer of plastic

between the two surfaces.

BUILDING FOUNDATIONS

a) Shallow foundation

b) Deep foundation

Shallow foundation

The depth of foundation is less than the breadth of foundation is called

Shallow foundation.

Types of shallow foundation

1. Wall footing

2. Isolated footing

3. Combined footing

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4. Continious footing

5. Strap footing

6. Grilllage footing

7. Raft foundation

Deep foundation

The depth of foundation is greater than the breadth of foundation is called

deep foundation.

Types of deep foundation

1. Classification based on function

2. Classification based on materials and composition

3. Well and caissons foundation

Classification based on function

1. Bearing piles

2. Friction piles

3. Screw piles

4. Compaction piles

5. Uplift piles

6. Sheet piles

Classification based on materials and composition

1. Cement concrete piles

2. Cast in situ piles

3. under reamed piles

4. Bored compaction piles

TEMPOARY WORKS

a) Centering

Temporary work used for construction of arches is called centering

b) Shuttering (form work) and de-shuttering

Temporary work used as a mould in which fresh concrete is poured for it

to harden is called shuttering and removing of shuttering work is called

deshutering.

c) Scaffolding

Temporary works erected for construction of masonry works, plastering,

Painting, etc is called scaffolding.

FABRICATION AND ERECTION OF STEEL STRUCTURES

The commonly used steel section in a structure as follows

1. Plate

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2. Flats

3. Angles

4. Channels

5. Joist

6. Tees

7. Z-bars

8. Rails

Equipments used in erection process

The following equipments are mainly used for steel erection process.

Such as Trusses, Frames, Braced domes

1. Cranes

2. Derrick poles

3. Power driven scotch derricks

4. Hand operated driven scotch derricks

5. Guy derricks cranes

6. Mobile cranes

7. Winches, Blocks and Jacks

8. Crawer tracks

Erection of building

Most of the buildings are purpose made and hence rarely identical. Even when

Identical building have to be erected, the chances are that site conditions will vary

to such extent that different erection procedures have to be adopted.

The following facts to be consider while selecting tackle for any construction.

1. Proposed method of erection

2. Speed of erection desired

3. Height of the structures

4. Reach required of the tackle

5. Weight and number of maximum lifts

WATER PROOFING

Application of water proofing materials makes the stone masonry free from

Efflorescence, dampness, frost action, etc.Generally heavy petroleum

Distillates, fatty oils, are excellent for waterproofing. These materials are

Applied as washing coat and they may cause some temporary discoloration.

Methods of water proofing

1. Brick jelly lime concrete terracing with or without tiles

2. Membrane water proofing with bituminous membrane

3. Thermal insulation combined with waterproofing for flat concrete roof

4. Water proofing and insulating Roofs by elastic membrane

5. Water proofing and insulating by mud phuska terracing with

Tile brick paving

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ROOF FINISHES

The upper part of the building is called roof. It protect from weathering

agent.

Roof covering

1. Tatch covering

2. Shingles

3. Tiles

4. Asbestos-cement sheets

5. Slates

AIR CONDITIONING OF BUILDING

It is the process of treating air as to control simultaneously its temperature,

humity, purity and distribution to meet the requirements of the conditioned

Space such comfort and health of human beings, needs of industrial process,

efficient working of commercial premises etc.

Purposes

1. It is required to preserve and maintained the health,

comfort, and convenient Of the occupants.

2. Improve the working condition of theatre,offices,

Banks, shops, etc.

3. Controlling the quality of air in the aero planes,

Railway coaches, road-car etc.

Classification air conditioning

1. Comfort air conditioning

2. Industrial air conditioning

3. Summer air conditioning

Principles of comfort Air conditioning

A feeling of comfort is a good indication of healthier atmospheric

Condition but this atmospheric condition, in turn, depends upon

The temperature, air motion and humity change for different season

Of the year

Hence the principle of air conditioning should involve the proper control

of temperature ,humity, and air velocity so as to suit the majority of people

throughout the year,givining the comfortable condition..

ACOUSTIC AND FIRE PROTECTION

Acoustic

The term ‘acoustic” may be defined as the science of sound and it describes

the orgion, propagation and sensation of sound.

Fire protection

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It is practically impossible to eliminate completely the changes of fire in a

Building as it is a facts no building material is fully fire –proof. Every

Building has some materials which catches the fire quickly.

Fire resisting materials

1. Stone

2. Brick

3. Timber

4. Glass

5. Cast iron

6. Steel

7. Concrete

General guide lines for fire resisting building

1. Alaram system

2. Protection of opening

3. Common wall

4. Stairs

5. Floors

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UNIT-II

2. SUB STRUCTURE CONSTUCTION 15HRS

SUB STRUCTURE CONSTRUCTION

Pipe Jacking method

In a situation where the sewerage pipes have to be laid in deeper ground (3 to 7

meters),the pipe jacking method will be adopted. This method not only minimizes the

digging of the trench to lay the new pipes but also alleviates disruption to the public.

. To form the pipe jacking or pipe

receiving station, a temporary shaft will

be set up at the proposed new manhole

location.

2. The soil in the temporary shaft is

excavated

3. The pipe jacking machine is then set

up at the base of the shaft. Upon confirmation of the alignment, the roller cutter at the

face of the cutting head machine cuts the soil in front of it.

4. The excavated soil is then fed to the crusher through a pipe and further crushed to

smaller pieces, after which it is transported up to the ground surface in a fluid form using

a slurry pump.

5. The excavated soil in slurry form is treated by passing it through a number of screens.

6. The dry spoil is then removed from site, so as to keep the works area clean.

7. The new pipe is lowered in sections behind the cutting head machine and gradually

pushed behind the cutting head machine into the area excavated. The excavation and pipe

installation cycle continues until the cutting head machine reaches the receiving station

with the new pipeline laid behind it.

8. A new manhole structure is then constructed in the receiving shaft.

9. Once the manhole construction is completed, the temporary shaft is backfilled and

surrounding area reinstated.

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10. Finally the manhole is cleaned and inspected by the relevant agency for handing

over and commissioning of the new line.

Pipe Jacking, also known as pipejacking or pipe-jacking, is a method of tunnel

construction where hydraulic jacks are used to push specially made pipes through the

ground behind a tunnel boring machine or shield. This technique is commonly used to

create tunnels under existing structures, such as roads or railways.

Tunneling

Tunnel Basics

A tunnel is a horizontal passageway located underground. While erosion and other forces

of nature can form tunnels, in this article we'll talk about man made tunnels -- tunnels

created by the process of excavation. There are many different ways to excavate a tunnel,

including manual labor, explosives, rapid heating and cooling, tunneling machinery or a

combination of these methods

Types of Tunnels

1. Mine tunnels

2. Public works tunnels

Mine tunnels are used during ore extraction, enabling laborers or equipment to access

mineral and metal deposits deep inside the earth. These tunnels are made using similar

techniques as other types of tunnels, but they cost less to build. Mine tunnels are not as

safe as tunnels designed for permanent occupation, however.

Public works tunnels carry water, sewage or gas lines across great distances. The

earliest tunnels were used to transport water to, and sewage away from, heavily populated

regions. Roman engineers used an extensive network of tunnels to help carry water from

mountain springs to cities and villages. These tunnels were part of aqueduct systems,

which also comprised underground chambers and sloping bridge-like structures

supported by a series of arches. By A.D. 97, nine aqueducts carried approximately 85

million gallons of water a day from mountain springs to the city of Rome.

Before there were trains and cars, there were transportation tunnels such as canals --

artificial waterways used for travel, shipping or irrigation. Just like railways and

roadways today, canals usually ran above ground, but many required tunnels to pass

efficiently through an obstacle, such as a mountain. Canal construction inspired some of

the world's earliest tunnels.

The Underground Canal, located in Lancashire County and Manchester, England, was

constructed from the mid- to late-1700s and includes miles of tunnels to house the

underground canals. One of America's first tunnels was the Paw Paw Tunnel, built in

West Virginia between 1836 and 1850 as part of the Chesapeake and Ohio Canal.

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Although the canal no longer runs through the Paw Paw, at 3,118 feet long it is still one

of the longest canal tunnels in the United States.

Photo courtesy Eric and Edith Matson Photograph

Collection/Library of Congress Prints and Photographs

Division

A Roman aqueduct that runs from the Pools of Solomon

to Jerusalem

Photo courtesy Kmf164/ Creation Commons Attribution Share-alike

License

Traveling through the Holland Tunnel from Manhattan to New

Jersey

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By the 20th century, trains and cars had replaced canals as the primary form of

transportation, leading to the construction of bigger, longer tunnels. The Holland Tunnel,

completed in 1927, was one of the first roadway tunnels and is still one of the world's

greatest engineering projects. Named for the engineer who oversaw construction, the

tunnel ushers nearly 100,000 vehicles daily between New York City and New Jersey.

Tunnel construction takes a lot of planning. We'll explore why in the next section.

Tunneling technique

Principal Benefits

The principal benefits of jacked box tunneling are:

A non-intrusive construction method

Minimal disturbance to surface infrastructure

Traffic flows maintained throughout the construction period

Traffic flows maintained with only minor restrictions during box installation

An efficient structural form incorporating a low bearing pressure foundation

A high quality maintenance free structure

Historical development

Jacked box tunneling in the UK developed from the. pipe jacking of the mid-1960s

Initially, small precast concrete boxes were jacked to form pedestrian subways and

portal bridge foundations. Later small boxes were jacked one on top Of another and filled

with concrete to form bridge abutments. In recent years, the development of high

capacity jacking equipment and sophisticated techniques for controlling ground

disturbance has led to the jacking of very large boxes each Capable of accommodating a

highway, railway or flood defense channel. Several large box structures have now been

installed in a wide variety of ground conditions.

Anti-drag systems

Referring to Fig. 1b, it can be seen that as the box is jacked forward it will tend to

drag the ground along with it. In the case of a wide box at shallow cover the mass of

ground on top of the box could be dragged forward, causing major disturbance and

possible disruption to the infrastructure above. Similarly, the underside of the box will

tend to drag and Shear the ground, resulting in remolding accompanied by a loss in

volume that will cause the box to dive. These effects are minimized by the use of a

proprietary anti-drag system (ADS) at the top and bottom of the box.

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Jacked box tunneling

The method in outline

Jacked box tunneling is a non-intrusive method for constructing a new under-bridge,

culvert or subway beneath existing surface infrastructure, for example railways and

highways.

The method enables traffic flows to be maintained throughout the construction period,

and maintained with only minor restrictions during the brief period of tunneling. The

inconvenience and costs of disruption to infrastructure and traffic flows experienced with

traditional construction methods can be avoided.

An example of the method is illustrated simply in Fig. 1. An open ended reinforced

concrete box is cast on a jacking base adjacent to a railway embankment, see Fig. 1a. A

purpose designed tunneling shield is provided at its leading end, and thrust jacks are

provided at its rear end reacting against a jacking slab. The box is then jacked slowly

through the ground under the railway in a carefully controlled tunneling operation, see

Fig. 1b. Excavation and jacking take place alternately in small increments of advance.

Measures are taken to ensure stability of the tunnel face and to prevent the ground from

being dragged forward by the advancing box. When the box has reached its final position,

Fig. 1c, the shield and jacking equipment are removed, and bridge construction is

completed with the addition of wing walls and road pavement.

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© Einstein College of Engineering

Tunnel Construction: Soft Ground and Hard Rock

Workers generally use two basic techniques to advance a tunnel. In the full-face method,

they excavate the entire diameter of the tunnel at the same time. This is most suitable for

tunnels passing through strong ground or for building smaller tunnels. The second

technique, shown in the diagram below, is the top-heading-and-bench method. In this

technique, workers dig a smaller tunnel known as a heading. Once the top heading has

advanced some distance into the rock, workers begin excavating immediately below the

floor of the top heading; this is a bench. One advantage of the top-heading-and-bench

method is that engineers can use the heading tunnel to gauge the stability of the rock

before moving forward with the project.

Notice that the diagram shows tunneling taking place from both sides. Tunnels through

mountains or underwater are usually worked from the two opposite ends, or faces, of the

passage. In long tunnels, vertical shafts may be dug at intervals to excavate from more

than two points.

Now let's look more specifically at how tunnels are excavated in each of the four primary

environments: soft ground, hard rock, soft rock and underwater.

Soft Ground (Earth)

Workers dig soft-ground tunnels through clay, silt, sand, gravel or mud. In this type of

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tunnel, stand-up time -- how long the ground will safely stand by itself at the point of

excavation -- is of paramount importance. Because stand-up time is generally short when

tunneling through soft ground, cave-ins are a constant threat. To prevent this from

happening, engineers use a special piece of equipment called a shield. A shield is an iron

or steel cylinder literally pushed into the soft soil. It carves a perfectly round hole and

supports the surrounding earth while workers remove debris and install a permanent

lining made of cast iron or precast concrete. When the workers complete a section, jacks

push the shield forward and they repeat the process.

Marc Isambard Brunel, a French engineer, invented the first tunnel shield in 1825 to

excavate the Thames Tunnel in London, England. Brunel's shield comprised 12

connected frames, protected on the top and sides by heavy plates called staves. He

divided each frame into three workspaces, or cells, where diggers could work safely. A

wall of short timbers, or breasting boards, separated each cell from the face of the

tunnel. A digger would remove a breasting board, carve out three or four inches of clay

and replace the board. When all of the diggers in all of the cells had completed this

process on one section, powerful screw jacks pushed the shield forward

.

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In 1874, Peter M. Barlow and James Henry Greathead improved on Brunel's design by

constructing a circular shield lined with cast-iron segments. They first used the newly-

designed shield to excavate a second tunnel under the Thames for pedestrian traffic.

Then, in 1874, the shield was used to help excavate the London Underground, the world's

first subway. Greathead further refined the shield design by adding compressed air

pressure inside the tunnel. When air pressure inside the tunnel exceeded water pressure

outside, the water stayed out. Soon, engineers in New York, Boston, Budapest and Paris

had adopted the Greathead shield to build their own subways.

Hard Rock

Tunneling through hard rock almost always involves blasting. Workers use a scaffold,

called a jumbo, to place explosives quickly and safely. The jumbo moves to the face of

the tunnel, and drills mounted to the jumbo make several holes in the rock. The depth of

the holes can vary depending on the type of rock, but a typical hole is about 10 feet deep

and only a few inches in diameter. Next, workers pack explosives into the holes, evacuate

the tunnel and detonate the charges. After vacuuming out the noxious fumes created

during the explosion, workers can enter and begin carrying out the debris, known as

muck, using carts. Then they repeat the process, which advances the tunnel slowly

through the rock.

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Fire-setting is an alternative to blasting. In this technique, the tunnel wall is heated with

fire, and then cooled with water. The rapid expansion and contraction caused by the

sudden temperature change causes large chunks of rock to break off. The Cloaca

Maxima, one of Rome's oldest sewer tunnels, was built using this technique.

The stand-up time for solid, very hard rock may measure in centuries. In this

environment, extra support for the tunnel roof and walls may not be required. However,

most tunnels pass through rock that contains breaks or pockets of fractured rock, so

engineers must add additional support in the form of bolts, sprayed concrete or rings of

steel beams. In most cases, they add a permanent concrete lining.

We'll look at tunnel driving through soft rock and driving underwater next

Other tunneling methods include:

Drilling and blasting

Slurry-shield machine

Wall-cover construction method.

Other uses

Excavation techniques, as well as the construction of underground bunkers and other

habitable areas, are often associated with military use during armed conflict, or civilian

responses to threat of attack. The use of tunnels for mining is called drift mining. One of

the strangest uses of a tunnel was for the storage of chemical weapons

Natural tunnel

Natural Tunnel State Park (Virginia, USA) features an 850 feet (259 m) natural

tunnel, really a limestone cave, that has been used as a railroad tunnel since 1890.

Punarjani Guha Kerala, India. Hindus believe that crawling through the tunnel

(which they believe was created by a Hindu god) from one end to the other will

wash away all of one’s sins and thus attain rebirth, although only men are

permitted to crawl through the cave.

Snow tunnels are created by voles, chipmunks and other rodents for protection and

access to food sources. Larger versions are created by humans, usually for fun.

For more information regarding tunnels built by animals, see Burrow

Temporary Way

During construction of a tunnel it is often convenient to install a temporary railway

particularly to remove spoil. This temporary railway is often narrow gauge so that it can

be double track, which facilitates the operation of empty and loaded trains at the same

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time. The temporary way is replaced by the permanent way at completion, thus

explaining the term Perway.

The diagram below shows the relationship between these underground structures in a

typical mountain tunnel. The opening of the tunnel is a portal. The "roof" of the tunnel,

or the top half of the tube, is the crown. The bottom half is the invert. The basic

geometry of the tunnel is a continuous arch. Because tunnels must withstand

tremendous pressure from all sides, the arch is an ideal shape. In the case of a tunnel, the

arch simply goes all the way around

Diaphragm Walls

A diaphragm wall is a reinforced concrete wall constructed in the ground using under

slurry techniques. Walls with widths of between 300mm and 1500mm can be formed in

this way to depths in excess of 60 meters.

Positive Features

Walls can be installed to considerable depths

Walls with substantial thickness can be formed

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The system is flexible in plan layout

The wall can easily be incorporated into the permanent works

The wall, or certain sections, can be designed to carry vertical load

Basement construction time can be reduced

Economical, positive solution for large, deep basements in saturated and unstable

soil profiles

Noise levels limited to engine noise only

No vibration during installation

Other Considerations

Not normally economical for small, shallow basements

The system needs a relatively large site area

Under certain conditions diaphragm walls may be used as cantilever, braced or tie-back

walls. Diaphragm walls are necessary :

in very unstable soil profiles below the water-table where continuous support and

watertight conditions are required to prevent mud flows, piping and erosion of the

soils;

where construction time is important and the use of a diaphragm wall can shorten

the programme;

in conditions where deeper than normal cantilever support may be required. These

conditions could occur where the wall is to act only as a cantilever, or where a

very deep initial excavation is required before the first braced or tie-back supports

can be installed.

Diaphragm wall is a kind of retaining wall which appropriate for using in a limited area

of work and better protection than the "Sheet Pile" type. Diaphragm wall can deep

penetrate vertically and perform as a pile in carrying the weight. Then this wall is best for

the building which has a deep foundation or many storeys of underground level. With

selected and carefully quality control for materials used such as concrete, steel bar, and

bentonite for stronger and better reinforcement.

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Typical Details for Diaphragm Wall Construction

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Diaphragm Wall Construction photos

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SHORING

Shoring is the process of placing props against the side of a structure, or beneath or above

anything, to prevent sinking or sagging.

During and after battle, ships may have occasion to support ruptured decks, to strengthen

weakened bulkheads, to build up temporary bulkheads against the sea, to support hatches

and doors, and to provide props for equipment that has broken loose. This is done largely

by shoring.

A shore is a portable beam. A wedge is a block, triangular on the sides and

rectangular on the butt end. A shole is a flat plate which may be placed under the end of a

shore to distribute weight or pressure. A strongback is a bar or beam, often shorter than a

shore, and used to distribute pressure or to serve as an anchor for a patch over a hole. Any

of the foregoing items can be made of metal or of wood.

Tools used for shoring

In addition to shores, wedges, Sholes, and strong-backs, the following tools, materials

and equipment are often used in connection with shoring

1. Axes.

2. Battens (wooden).

3. Bolts, nuts and washers.

4. Canvas.

5. Chain falls.

6. Chisels (cold).

7. Chisels (wood).

8. Electric welding machine.

9. Hammers (claw).

10. Hatchets.

11. Hydraulic jacks.

12. Mattresses.

13. Mauls and sledges.

14. Nails.

15. Oxyacetylene cutting torches.

16. Pillows.

17. Plugs (wooden).

18. Sand.

19. Saws (carpenter's hand).

20. Saws (lumberjack's cross-cut).

21. Screw jacks

22. Sheet packing.

23. Turnbuckles.

24. Wire (binding).

25. Wire hawser.

26. Wood clamps

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© Einstein College of Engineering

© Einstein College of Engineering