Civil construction project report at kmda

PROJECT REPORT

Submitted to

Kolkata metropolitan development authority

TRAINING PERIOD: 19 TH MAY 2014-18 TH MAY 2015

Submitted by:

AVIJIT BANERJEE

ACKNOWLEDGEMENT

It is indeed a great pleasure and privilege to present this report on training At K.M.D.A.The internship opurtunity I had with K.M.D.A was a great chance for learning and development ,therefore I consider myself as a very lucky person as I was provided with an opportunity to be a part of it.I am also grateful for having a chance to meet so many wonderful people and professionals who led me through this internship period.

I am extremely grateful to my training and placement officer for issuing a Training letter, whichmade my training possible at K.M.D.A(R.E SECTOR).

I would like to express my gratitude to and special thanks to Executive Engineer of K.M.D.A (R.E SECTOR) MR.TAPAN DAS and MR. TULSI DAS PRAMANIK inspite of being extraordinarily busy with their duties ,look time out to hear, guide and keep me on the correct path and allowing me to carry the project at their esteemed organization .

I would also thank to Assistant Engineers of K.M.D.A (R.E SECTOR) MR.SUPRIYO PAL and MR. PRADIP BARUA.

I further express my deepest gratitude to AVIJIT BISWAS,Technical Assistant of K.M.D.A (R.E SECTOR) without whose suggestions and brotherly affection to me I could not complete this project.

Thanks to all other K.M.D.A officials and all other members of K.M.D.A, yet uncounted for their help in completing the project and see the light of success.

KOLKATA METROPOLITAN DEVELOPMENT AUTHORITY ,R.E SECTOR Page 2

ABOUT K.M.D.A Kolkata Metropolitan Development Authority (K.M.D.A) is the statutory planning and development authority for the Kolkata Metropolitan Area (K.M.D.A) in the state of West Bengal, India. The organisation was previously known as Calcutta Metropolitan Development Authority (CMDA) and still retains the previous logo. KMDA is under the ministry of Municipal Affairs and Urban Development of West Bengal state government.

KMDA's role is multi disciplinary - it is the agency of city planning, it sculpts new areas and townships, it develops physical infrastructure as well as provide basic services like water, drainage, waste management. Besides these KMDA is also the Technical Secretariat to Kolkata Metropolitan Planning Committee (KMPC).

The organisation was initially formed under a Presidential Ordinance in 1970. It works now under provision of the West Bengal Town and Country (Planning & Development) Act, 1979. Its Planning Directorate was set up in 1974.


Project site 1

Name of the work

Conversion of existing open air hall to auditorium hall of nazrul mancha at Kolkata


Index

Contents page no.

ABOUT 6

INTRODUCTION 6

CALCIUM SILICATE BOARD 6

GLASS WOOL 7

USES OF ETCHING TOUGHENED GLASS 8

FALSE CEILING 9

USES OF ARMAFLEX RUBBER 10

SOME MISCELLANEOUS WORKS 11


ABOUT

Nazrul Mancha is an auditorium in Kolkata, India. Noted for the Dover Lane Music Conference, the open-air theatre becomes the centre of attention for music lovers when it becomes the venue for the Dover Lane Music Conference in January each year. For four consecutive nights music lovers are treated to musical performances.

INTRODUCTION

Muktangan, the city's first - and only - open air theatre, was made for the largest air-conditioned hall in Kolkata. Built in 1980 and rechristened as Nazrul Mancha a decade later, when an overhead steel frame was added to provide a corrugated tin sheet roof, the facility soon became a popular venue for high-profile music concerts. The facility, owned by the Kolkata Improvement Trust, was renovated by the

Kolkata Metropolitan Development Authority (KMDA).

The threatre has been also be fitted with a state-of-the-art fire fighting system. A reservoir is being created to meet the system's needs. The interiors of the hall be renovated. Nothing much has to be done externally to keep the heritage of the place alive.

BEFORE RENNOVATION after renovation

USES OF CALCIUM SILICATE BOARD

Calcium silicate (often referred to by its shortened trade name Cal-Sil or Calsil) is the chemical compound Ca2SiO4, also known as calcium ortho silicate and sometimes formulated 2CaO.SiO2.

Calcium silicate is commonly used as a safe alternative to asbestos for high temperature insulation materials. Industrial grade piping and equipment insulation is often fabricated from calcium silicate. Its fabrication is a routine part of the curriculum for insulation apprentices. One of the most successful materials in fireproofing in Europe is calcium silicate. Where North Americas use spray fireproofing


plasters, Europeans are more likely to use cladding made of calcium silicate. High performance calcium silicate boards retain their excellent dimensional stability even in damp and humid conditions and can be installed at an early stage in the construction program, before wet trades are completed and the building is weather-tight. For sub-standard products, silicone treated sheets are available to fabricators to mitigate potential harm from high humidity or general presence of water. Fabricators and installers of calcium

silicate in passive fire protection often also install firestops . so it was used in nazrul mancha as a coated bluish white colour outside.

GLASS WOOL

Glass wool is an insulating material made by glassfibres. arranged using a binder into a texture similar to wool. Glass wool is produced in rolls or in slabs, with different thermal and mechanical properties. It may also be produced as a material that can be sprayed or applied in place, on the surface to be insulated.

Principles of function

Gases possess poor thermal conduction properties compared to liquids and solids, and thus makes a good insulation material if they can be trapped. In order to further augment the effectiveness of a gas (such as air) it may be disrupted into small cells which cannot effectively transfer heat by natural convection. Convection involves a larger bulk flow of gas driven by buoyancy and temperature differences, and it does not work well in small cells where there is little density difference to drive it.In order to accomplish formation of small gas cells in man-made thermal insulation, glass and polymer materials can be used to trap air in a foam-like structure.


Uses of glass wool

Glass wool is a thermal insulation that consists of intertwined and flexible glass fibers, which causes it to "package" air, resulting in a low density that can be varied through compression and binder content . Glass wool can be a loose fill material, blown into attics, or, together with an active binder sprayed on the underside of structures, sheets and panels that can be used to insulate flat surfaces such as cavity wall insulating purpose, ceiling tiles, curtain walls as well ducting. It is also used to insulate piping and for sound proofing.

USES OF ETCHING TOUGHENED GLASS

What is toughened glass?

Toughened glass is physically and thermally stronger than regular glass. The greater contraction of the inner layer during manufacturing induces compressive stresses in the surface of the glass balanced by tensile stresses in the body of the glass. For glass to be considered toughened, this compressive stress on the surface of the glass should be a minimum of 69 mega pascals (10,000 psi). For it to be considered

safety glass, the surface compressive stress should exceed 100 mega pascals (15,000 psi). The greater the surface stress, the smaller the glass particles will be when broken.It is this compressive stress that gives the toughened glass increased strength.

Etching

Etching refers to the technique of creating art on the surface of glass by applying acidic, caustic, or abrasive substances.

Techniques

Various techniques are used to achieve an etched surface in glass, whether for artistic effect, or simply to create a translucent surface.


Acid etching is done using hexafluorosilicic acid (H2SiF6) which, when anhydrous, is colourless. The acid is prepared by dissolving silica in a mixture of hydrofluoric acid, quartz powder, calcium fluoride, and concentrated sulfuric acid derived after heating.

Glass etching cream is used by hobbyists as it is generally easier to use than acid. Available from art supply stores, it consists of fluoride compounds, such as hydrogen fluoride and sodium fluoride (which are still very dangerous). As the types of acids used in this process are extremely hazardous, abrasive methods have gained popularity.

FALSE CEILING

false celing is used to conceal the air condition and electrical appliances and the fault in plastering.

it has an unavoidable aesthetic function .false ceiling increases the inner beauty of the room.

It is also essential for accentuating the lighting of the room.it is a neccessary part of cove lighting and indirect lighting. false ceiling is also necessary for making arrangements for the lighting accessories, for lighting given at two or three levels and for uplighting. It also decreases the heat of the room.

FALSE CEILING IN NAZRUL MANCHA

For increasing the accoustics of the home theatre room,false ceiling is used.

The ceiling panels of false ceiling can be easiliy removed .it helps in the repairing and maintenance of air

conditioning, plumbingand wiring accessories by provi ding quick access to them.

USED OF M.D.F BOARD FOR FALSE CEILING PURPOSE

M.D.F (medium-density fiber board is an engineered wood product made of fine wood chips. M,D,F boards has been easily transformed into suspended ceiling in that auditorium.. Because of perforation,

ventilation systems and diffuse cells can be placed behind the boards to avoid the damage of the room interior


USES OF ARMAFLEX RUBBERAF/Armaflex Class O is the flexible, closed cell, elastomeric nitrile rubber insulation that offers reliable protection against condensation and effectively prevents energy loss. It is a grey elastomeric foam sheet supplied in rolls and especially produced for the thermal and acoustic insulation of metal air-conditioning ducts.

Air ducts are not only insulated in order to minimize heat and energy losses and, in the case of outdoor air ducts or air-supply and exhaust ducts running through cool rooms, condensation can occur on the surface or on the inside of the duct if the temperature falls below the dew point. Insulation must be installed to prevent this and also to reduce the emission of air and structure-borne sound, which occurs due to flow noise in the air ducts. In addition Armaflex engenders improved indoor air quality by making it more difficult for micro-organisms, such as mould, to settle.

Duct has been made with coated out side with armaflex rubber and inside with glasswool.

SOME MISCELLANEOUS WORKS

An old roller of Jessop has been painted new with a doll as a driver of human size for memento.


Old plastic chairs has been replaced by back push auditorium chair.

Pave block has been laid in passage.


PROJECT SITE 2

Name of the work

CONSTRUCTION OF WOMENS COLLEGE with allied works for minority within the campus of jnan Chandra ghosh POLYTECHNIC

TENDER NO.

SE(W)/C-II/RE/KMDA/24 OF 2013-2014

agency

m/s madhumita construction pvt.ltd.


Index

Contents page no.

INTRODUCTION AND IMPORTANT INFORMATION 14

SITE CLEARANCE 15

POSITIONING OF CENTRAL COORDINATE AND LAYOUT 15

EARTH WORKING EXCAVATION 15

PUMPING OUT OF WATER 16

BRICK WORK IN PERIPHERY WALL 16

SILVER SAND FILLING 16

FOUNDATION LAYOUT AND CENTRELINE EVALUATION 17

SINGLE BRICK FLAT SOLING 17

PLAIN CEMENT CONCRETE (P.C.C) 18

R.C.C FOOTING 20

R.C.C COLUMN CONSTRUCTION 21

R.C.C ROOF SLAB CASTING PROCEDURE 23

BRICK WORK 29

PLASTERING 31


INTRODUCTION AND IMPORTANT INFORMATION

The proposed minority women’s college consists of three buildings – Academic 1, Academic 2 and Administrative building, where Academic 1 and Academic 2 are identical. Each building are three storied.

INFORMATION

1. Grade of reinforcement is tor steel deformed bar of grade Fe-500

2. Clear cover to main reinforcement

A) Column =40 mm

b) Floor beams= 25 mm

c) Floor Slab/Waist slab =20 mm

3. Lap length = 50* Diameter of bar

4. All chair bars in slab is 10 tor @1000c/c

5. all spacer bar is 25 tor @1000c/c

6 .all distributor steel 8 tor @ 25 c/c

Foundation –Strip footing


SITE CLEARANCE -

The very first step is site clearance, which involves removal of grass and vegetation along with any other

objections, which might be there in the site location.

Positioning of Central coordinate and layout -

The centre point was marked with the help of a digital Theodolite, Thread and Plumb bob as per the grid drawing. With respect to this centre point, all the other points of columns were to be decided so its exact position is very critical.

EARTHWORKING EXECAVATION

This is the primary part of building construction. Excavation was carried out mechanically. A hydraulic excavator (Tata Hitachi ex-200) was used for excavated the soil & two dumpers were used for carried the excavated soil & stack them on another place nearby. Adequate precautions are taken to see that the excavation process do not damage the adjoining structures. Excavation was carried out providing

adequate slide slopes & dressing of excavation bottom. Earthwork excavated up to 2675 mm.

Two hydraulic excavators during excavation


PUMPING OUT OF WATER After excavation, two pumps were used to remove the stagnant

water as far as possible. This was the hard task in this project, because it was the monsoon season.

BRICK WORK IN PERIPHERY WALL

SILVER SAND FILLING After excavation, the cut out portion was filled up with silver sand. This

filled up process was controlled by dumper and backhoe loader (JCB). Silver sand filled upto 1500 mm.


After sand filing it was compacted by PLATE COMPACTOR with sprinkling water.

FOUNDATION LAYOUT AND CENTERLINE EVALUATION This is one of the important part

of building construction. To determine the centreline as per plan the used instrument was digital theodolite (for measure horizontal and vertical angle), peg , nail , hammer ,tread. This was my first experience using digital theodolite to determine gridline as per plan.

SINGLE BRICK FLAT SOLING In which land the soling process did ,before that compacted by

plate compactor machine with using water. To hold the grid line mason are laid the brick.the instrument

was used in this process thread ,plumb bob ,measuring tape


first of all, compact the surface by hand rammer and sprinkling water.

Lay the bricks on surface so that they contact with each other. And keep the frog mark upwards.

Fill the gaps or joints among the bricks with sand.

Finally check the finish surface is levelled both longitudinally and transversely.

P.C.C (PLAIN CEMENT CONCRETE)

after finished 75 mm thick brick flat soling ,the next step was p.c.c .for p.c.c plain cement also called only “cement concrete” or “binding concrete”.


Materials used for producing pcc

Cement: the cement used in site was Portland pozzolona cement as bonding material.

Fine aggregate: sand as used as fine aggregate.

Coarse aggregate: stone chips used for this purpose

Water: pure drinkable water used in pcc.

Tools used for producing pcc

Normally used tools in the site for pcc

Wooden rammer

Mixture machine (tilting mixture was used)

Thickness of pcc was 100 mm.

Placing and compaction of pcc

first step was formwork for p.c.c with ply board as per specified dimensions. then clean dust or foreign or

loose earth from concreting area placed the concrete gently from one side .used the mixed concrete

within 45 minutes after the water was added. then used wooden rammer for compaction and finishing pcc

.checked the finish level of pcc by thread fixed with nails in form work.


RCC FOOTING

The type of footing used was Strip foundation.it consist of a continuous strip , usually of concrete,formed centrally under load bearing walls.this continuous strip serves as a level base on which the wall is built and is of such the built and is of such a width as is necessary to spread the load on the foundations to an area of subsoil capable of supporting the load without undue compaction .

The width of a concrete strip foundation depends upon the bearing capcity of the subsoil and the load on the foundations.the greater the bearing capacity of the subsoil the less the width of the foundation for the same load.

Arrangement of bars

After the pcc process had been done , the steel bars was laying on the spot,as per bar bending schedule.main bar had been laid along shorter span and distribution bar along longer direction.dia of main bar used in this purpose of footing was 12 mm and 16 mm And distribution was 8 mm diameter as per plan.


Cover block then used in the footing . it is Prevent steel bars from getting exposed to the atmosphere so that steel corrosion may result.

RCC COLUMN CONSTRUCTION

RCC (Reinforced Cement Concrete) column is a structural member of RCC frame structured building. It's a vertical member which transfers loads from slab and beam directly to subsequent soil.

A whole building stands on columns. Most of the building failure happens due to column failure. And most of the column failure happens not for design fault but for the poor construction practice. So, it is very important to know the construction process of the RCC column properly.

Two types of dimension the column at site were (350*450)mm and (300*450)mm. but their tie bars position and longitudinal bars dia were different.

Constructing RCC (Reinforced Cement Concrete) Column involves following four stages of works -

1. Column layout work


2. Column reinforcement work3. Column formwork, and4. Pouring concrete into column.

1. Column layout work: In this stage of works the location of columns are determined practically in field. It is done by laying rope according to grids shown in the drawing and then mark the location of columns related to rope.

In drawing, column locations are shown related to grid-line with dimension. Practically, in field, ropes are our grid-line. So we place columns related to rope-line by measuring dimension shown in the drawing.

2. Column Reinforcement work: After marking the column locations, we then start to place reinforcement as instructed in the structural drawing.

3. Column formwork: In building, floor height is normally kept 10 feet. If the slab has beam then we have to pour concrete up to beam bottom level. Suppose, beam height specified in drawing is 1'-6". So, the casting height of our column will be 8'-6". And our formwork height will be 8'-6". But one thing should be considered here is that dropping concrete from above 5' height isn't suggested during pouring. Because it leads concrete segregation. So we should make one-side of column formwork within 5 feet height range. After casting 5 feet of column, we just lift the short side up to full-casting height of column next day.


4. Pouring concrete into column: Casting column is easy. For small quantity of concrete volume we normally depend on machine-mix concrete and for large concrete quantity ready-mix concrete. In my site machine mix concrete has been used.

precaution taken on column work

All rubbish, particularly chippings, shavings and saw dust, was removed from the interior of the forms (plywood) before the concrete is placed. The form work in contact with the concrete was cleaned and thoroughly wetted or treated with an approved composition to prevent adhesion between form work and

concrete. Care was taken that such approved composition is kept out of contact with the reinforcement.

The form-work should be designed and constructed such that the concrete can be properly placed and thoroughly compacted to obtain the required shape, position, and levels subject.


All the outer columns of the frame were checked for plumb by plumb-bob as the work proceeds to upper floors. Internal columns were checked by taking measurements from outer row of columns for their exact position. Jack were used to lift the supporting rods called props.

RCC ROOF SLAB CASTING PROCEDURE

Materials and machinery used

Rmc vehicle

Concrete pump

Vibrators

Scope of the work

Marking the slab

Arrangement and placing the reinforcement

Form work for slab

Placing the concrete

Before casting of slab, staging is very necessary. it made of ply .for this purpose presence of skilful labours needed and it was happened in site.

Reinforcement


It shall be as per BBS prepared according to approved drawing. The R/F shifting and binding shall be started as soon as shuttering is completed. R/F binding shall continue as formwork and shuttering work is progresses.

Test conducted before placement

Before concrete placement workability had been done. for this slump test had been occurred.

Concrete Slump Test

Slump is a measurement of concrete's workability, or fluidity.

It's an indirect measurement of concrete consistency or stiffness.

A slump test is a method used to determine the consistency of concrete. The consistency, or stiffness, indicates how much water has been used in the mix. The stiffness of the concrete mix should be matched to the requirements for the finished product quality

Concrete Slump Test

The concrete slump test is used for the measurement of a property of fresh concrete. The test is an empirical test that measures the workability of fresh concrete. More specifically, it measures consistency between batches. The test is popular due to the simplicity of apparatus used and simple procedure.

Principle

The slump test result is a measure of the behavior of a compacted inverted cone of concrete under the action of gravity. It measures the consistency or the wetness of concrete.

Apparatus


Slump cone,

Scale for measurement,

Temping rod (steel)

Procedure of Concrete Slump test:

The mold for the slump test is a frustum of a cone, 300 mm (12 in) of height. The base is 200 mm (8in) in diameter and it has a smaller opening at the top of 100 mm (4 in).

The base is placed on a smooth surface and the container is filled with concrete in three layers, whose workability is to be tested .

Each layer is temped 25 times with a standard 16 mm (5/8 in) diameter steel rod, rounded at the end.

When the mold is completely filled with concrete, the top surface is struck off (leveled with mould top opening) by means of screening and rolling motion of the temping rod.

The mould must be firmly held against its base during the entire operation so that it could not move due to the pouring of concrete and this can be done by means of handles or foot - rests brazed to the mould.

Immediately after filling is completed and the concrete is leveled, the cone is slowly and carefully lifted vertically, an unsupported concrete will now slump.

The decrease in the height of the center of the slumped concrete is called slump.

The slump is measured by placing the cone just besides the slump concrete and the temping rod is placed over the cone so that it should also come over the area of slumped concrete.

The Degree of workability

slump Compacting factor Use for which concrete is suitable

mm in


Very low 0-25 0-1 0.78 Very dry mixes; used in road making. Roads vibrated by power operated machines..

low 25-50 1-2 0.82 Low workability mixes; used for foundations with light reinforcement. Roads vibrated by hand operated Machines

Medium 50-100 2-4 0.92 Medium workability mixes; manually compacted flat slabs using crushed aggregates. Normal reinforced concrete manually compacted and heavily reinforced sections with vibrations.

High 100-175 4-7 0.95 High workability concrete; for sections with congested reinforcement.

140 mm slump used in this site.

placement of concrete.

through the rmc van the casting process occurred. Proper walkways/platforms had been arranged so that the supports of the pipeline and manpower are not directly stand on reinforcement.

Sufficient carpenters along with supervisor shall inspect the behavior of supports below the slab during the casting. Extra Props had been stocked below slab to provide additional supports in case of any failure of supports.


General precautions

Before casting of slab Check concealed electric conduit work, junctions and all electrical points, positions of fan points,

MS boxes as per electrical layout plan Check the reinforcement and obtain approval from RCC consultant Decide the position of concrete joints in case of a big slab after consulting the RCC consultant Ensure removal of wooden pieces, paper, nails, etc. from slab/ beam before casting Ensure that shuttering, support and scaffolding is firm and proper Ensure all joints in formwork are properly sealed to avoid slurry leakage. Instead of using mud,

jute, paper, etc. it is desirable to use putty of used grease and cement (50 : 50). It effectively seals joints and remains intact during vibration of concreting.

i. Make arrangement of wooden planks and steel chairs and place them on slab for labour movement. Do not allow labour to directly walk on reinforcement

ii. Check if vibrator is in working condition and adequate labour is availableiii. Sprinkle little water over shuttering just before placing the concreteiv. Ensure sufficient light arrangements in case of late evening/night concreting and provide

safety measuresv. Ensure that concrete cover blocks of proper size & type are provided at site as per

requirement of BIS standards

At the time of casting


Check and ensure that the position of cover blocks are intact and not disturbed during concreting operations

Closely supervise the proper batching of ingredients, water content, mixing and testing of fresh concrete in case of concrete made at site.

Beams had been cast first in layers and properly compacted with vibrators One carpenter & helper should be present below slab shuttering to ensure that props/supports

are not disturbed and shuttering remains intact in position during & after concreting also One bar bender should be present to ensure that no displacement of steel reinforcement takes

place

After concreting of slab Deshuttering of vertical sides of beam, columns only after 24 hours Curing of slab for 14 to 20 days depending upon the type of structure Deshuttering of slab after 7, 10 or 15 days depending upon span of slab and type of cement used Deshuttering of beams after 14 or 21 days depending upon span Checking all spots of honeycombing and finishing the same with rich cement sand mortar.

Brick work


Brickwork is an important part of construction work done with the help of bricks and cement mortar. Types of the brick depends upon the importance of the work. 250 mm thick main wall and 125 mm thick partition walls had been done.

Cement sand ratio in the mortar was 1:4

Tools recommended for brick work

1. Wooden setting out square2. Spirit level3. Water level4. Boning rod5. Plumb rule6. Laying trowel7. Brick hammer8. Lump hammer and bolster chisel.9. Double end comb hammer10. Straight edge11. Brick work gauge rod12. Checking the accuracy of spirit plumb level

How to test the quality of Bricks at small construction sites?

Normally the bricks are tested for Compressive strength, water absorption, dimensional tolerances and efflorescence. However at small construction sites the quality of bricks can be assessed based on following, which is prevalent in many sites.

1. Visual check - Bricks should be well burnt and of uniform size and color.

2. Striking of two bricks together should produce a metallic ringing sound.

3. It should have surface so hard that can’t be scratched by the fingernails.

4. A good brick should not break if dropped in standing position from one metre above ground level.

5. A good brick shouldn’t absorb moisture of more than 15-20% by weight, when soaked in water For


example, a good brick of 2 kg shouldn’t weigh more than 2.3 to 2.4 kg if immersed in water for 24 hours

Working procedure

All the bricks to use in construction are soaked well in water so that they did not absorb water from the mortar.mortar was spread on the top of the foundation course over an area to be covered by the edges of the wall. the corner of the wall was constructed first .the excess mortars from the sides will squeeze out,which was cleaned up with trowel. the level and alignment checked. Bricklayers has been checked vertical by plum bob.

Precautions to be taken in brick masonry work• Bricks should be soaked in water for adequate period so that the water penetratesto its full thickness. Normally 6 to 8 hours of wetting is sufficient.

• A syst• All bricks should be placed on their bed with frogs on top (depression on top of thebrick for providing bond with mortar).• Thread, plumb bob and spirit level should be used for alignment, verticality andhorizontality of construction.• Joints should be raked and properly finished with trowel or float, to provide good bond.• A maximum of one metre wall height should be constructed in a day.• Brickwork should be properly cured for at least 10 days.


PLASTERING

The purposes of plastering are to give a wear resistance to the wall, increase fire resistance of the building elements, and to give a good appearance to the wall. plastering conceals defective workmanship and cover up unsound and cheap quality material.

Necessary handling equipment

1. Hand gloves 2. Bucket 3. Spread4. Trowel5. Pan6. Float 7. Plumb bob


Step by Step Guide for Cement Plastering

Step-1 (Preparation of Surface for Plastering)

1. Keep all the mortar joints of wall rough, so as to give a good bonding to hold plaster.2. Clean all the joints and surfaces of the wall with a wire brush, there should be no oil or

grease etc. left on wall surface.3. If the surface is smooth or the wall to be plastered is old one, then rake out the mortar

joint to a depth of at least 12 mm to give a better bonding to the plaster.4. If the projection on the wall surface is more than 12 mm, then knock it off, so as to obtain

a uniform surface of wall. This will reduce the consumption of plaster.5. If there exist any cavities or holes on the surface, then fill it in advance with appropriate

material.6. Roughen the entire wall to be plastered.7. Wash the mortar joints and entire wall to be plastered, and keep it wet for at least 6 hours

before applying cement plaster.

Step-2 (Applying First Coat or Under Coat or Rendering Coat)

1. In case of brick masonry the thickness of first coat plaster is in general 12 mm and in case of concrete masonry this thickness varies from 9 to 15 mm.

2. The ratio of cement and sand for first coat plaster varies from 1:3 to 1:6.3. Apply the first coat of plaster between the spaces formed by the screeds on the wall

surface. This is done by means of trowel.4. Level the surface by means of flat wooden floats and wooden straight edges.5. After leveling, left the first coat to set but not to dry and then roughen it with a scratching

tool to form a key to the second coat of plaster.

Step-3 (Applying Second Coat or Finishing Coat or Fine Coat)

1. The thickness of second coat or finishing coat may vary between 2 to 3 mm.2. The ratio of cement and sand for second coat plaster varies from 1:4 to 1:6.3. Before applying the second coat, damp the first coat evenly.


4. Apply the finishing coat with wooden floats to a true even surface and using a steel trowel, give it a finishing touch.

5. As far as possible, the finishing coat should be applied starting from top towards bottom and completed in one operation to eliminate joining marks.

After completion of the plastering work, it is kept wet by sprinkling water for at least 7 days in order to develop strength and hardness.


PROJECT SITE 2

Name of the work

REPAIR, RECTIFICATION AND UP-GRADATION WORK OF KING’S BUILDING IN THE CAMPUS OF JNAN CHANDRA GHOSH POLYTECHNIC

TENDER NO

SE(W)/C-I/RE/KMDA/12 OF 2014-2015

agency

m/s standard engineers


Index

Contents page no.

INTRODUCTION 36

PROBLEM OF THE BUILDING 38

REPAIR OF PLASTER ON WALLS 38

ROOF RENOVATION 40

SOME MISCELLANEOUS WORK 43


INTRODUCTION

King's building is the heritage building situated within the campus of jnan Chandra ghosh polytechnic campus.The building is a full of architectural work inside the

building.

such as Bifurcated stair, beautiful veranda, mumpty room.The wall of the building is 500mm(20”)thick.

BIFURCATED STAIR


verandah

rooms of the building is quite large & its ceiling height is approximately same to modern conventional buildings 1st floor height.floor is consisstof floor beam which is I section floor beam made from

frodinham ,England.

Roof of the building made of lime terracing & tile.


LIME TERRACING WITH TILE

PROBLEM OF THE BUILDING After elapses of the long time the rooftop of the building had been seriously damaged. So the repair and rectification of the building had to properly upgraded.

REPAIR OF PLASTER IN WALLS

Repair of plaster is needed from time to time as the building ages.the plaster repair work includes cutting the patch and preparing the wall surface.

Procedure involves in repair of plaster are:

Setting up scaffolding

Scaffolding if required for the proper execution of the repair work should be erected .ladder can also be used in case of scaffolding if the work can be done safely.


Cutting of old plaster

The mortar of the patch was cut to a square or rectangle shape at position where repairing is needed.

Preparation of surface

It is necessary things to do before plastering.the old plaster was throughly scrubbed with wire brushes after the plaster had been cut out and marked the surface is roughned by wire brushing and all the dust and loose particles cleaned off.

In kings building internal walls surface had been washed and cleaned and kept wet .

Application of plaster

Mortar of specific mix 1:4 with the good quality plaster sand was used.with the cement mortar dr.fixits lw+ damp proof chemical used.

Curing of plaster

Curing of plaster had been done for 3 days at regular interval.


ROOF RENOVATION

Tree roots had seriously damaged the most section of lime concrete roof. Therefore, decision had been taken by authorities to replace the old roof with rcc slab.

RCC ROOF CASTING PROCEDURE

Materials and machinery used

Rmc vehicle

Concrete pump

Vibrators

Scope of the work

Marking the slab

Arrangement and placing the reinforcement

Form work for slab

Placing the concrete

Before casting of slab, staging is very necessary. it made of ply .for this purpose presence of skilful labours needed and it was happened in site. After ply laying process plastic sheet had been laid so that the slurry had not drop drown in time of slab casting.


placement of concrete.

Through the rmc van the casting process occurred. Proper walkways/platforms had been arranged so that the supports of the pipeline and manpower are not directly stand on reinforcement. Sufficient carpenters along with supervisor shall inspect the behavior of supports below the slab during the casting. Extra Props had been stocked below slab to provide additional supports in case of any failure of supports.


At the time of casting

Check and ensure that the position of cover blocks are intact and not disturbed during concreting operations

Closely supervise the proper batching of ingredients, water content, mixing and testing of fresh concrete in case of concrete made at site.

One carpenter & helper should be present below slab shuttering to ensure that props/supports are not disturbed and shuttering remains intact in position during & after concreting also

One bar bender should be present to ensure that no displacement of steel reinforcement takes place


After concreting of slab Curing of slab for 14 to 20 days depending upon the type of structure Deshuttering of slab after 7, 10 or 15 days depending upon span of slab and type of cement used

Some miscellaneous work

Septic tank construction

Arch construction



SOME IMPORTANT BUILDING CONSTRUCTION TERMS RELATED TO PROJECT 2

Some important terms ,which I’ve learned in site.

SHUTTERING OR FORMWORK

Formwork is a mould or die used to support and shape the concrete until it attains sufficient to carry its own weight. The formwork holds the concrete until it hardens to required shape and size.it is maid by hard wood for interior works and steel plate for superior works and they are supported by staging of bamboo,salballah,structural tubing.

SIGNIFICANCE OF FORMWORK

1) Formwork constitutes 30% of the cost and 60% of the time in concrete construction.

2) Quality of concrete finish and soundness of concrete depends very much on the formwork system

3) Desired shape of concrete is not possible if formwork not done properly.

4) Formwork should be properly designed, fabricated and erected to receive concrete.

5) Accidents happen because of the faulty formwork and scaffolding or staging.


SAFETY IN USING FORMWORK

1) Components are light in weight for manual handling.

2) Loose or hanging components are minimal.

3) Appropriate use of tools.

4) Minimum operations are involved in each reuse

STAGING

Staging is for the purpose of site work for the purpose of site work for the labour worker .upon which shuttering work or form work is done by labour work. it generally made by wooden

ply ,steel plate.

PROP

Prop is metal item, generally made of iron rod or bamboo. iron rod used in the site of gyan ghosh premises. its purpose is support the stage and it can be adjustable.


SCAFFOLDING

Scaffolding is a temporary structure used to support people and material in the construction or repair of building and other structures.

Scaffolding has been used since ancient times.there are many kinds of prefabricated ,modular system of metal pipes or tubes ,although it can be custom made from other materials such as wood and bamboo

which is frequently used in south east asia.


SPACER BAR

Where there are two or more row of bars ,the bars shall be vertically in line and the minimum vertical distance between the bars shall be 15 mm, two thirds the nominal maximum size of coarse aggregate or the maximum size of bar whichever is geatest.the vertical distance may be maintained by providing

spacer bars placed 0.9 m-1.2 m,apart fromn one another through out the length of the beam.

COVER BLOCK

Cover blocks are placed to prevent the steel rods from touching the shuttering plates and there by providing a minimum cover and fix the reinforcements as per the design drawings. Sometimes it is commonly seen that the cover gets misplaced during the concreting activity. To prevent this, tying of cover with steel bars using thin steel wires called binding wires (projected from cover surface and placed during making or casting of cover blocks) is recommended. Covers should be made of cement sand mortar (1:3).Shape of the cover blocks could be cubical or cylindrical. However, cover indicates thickness of the cover block. Normally, cubical cover blocks are used.

COVER BLOCK PREPARATION


COVER BLOCK IN FOOTING

PURPOSE OF COVER BLOCK Prevent steel bars from getting exposed to the atmosphere so that steel corrosion may result.Place and fix reinforcement based on design drawing.

Structural element

Cover to reinforcement (mm)

Footings 40Columns 40Slabs 15Beams 25

CHAIR BAR


It maintains the gap between the two layer of bar.

It supports the bars .

it helps to prevent the fear of building collapse due to the failure of compression and tension zone.

RMC

Full form of r.m.c is ready mixed concrete, that is manufactured in a factory or batching plant , according to a set recipe, and then delivered to a worksite ,by truck mounted in transit mixtures.this results in a precise mixture , allowing specially concrete mixtures to be developed and implemented on construction sites.the first rmc plant was installed in uk.and in india it was first established in 1950. The nominal

capacity of rmc was used on project II 6.5 cubic meter.

COMPACTION BY VIBRATOR

it is pointed out that the compaction by hand, if properly carried out on concrete .with sufficient workability, gives satisfactory results, but the strength of the hand compacted concrete will b e necessarily low ,because of higher water cement ratio required for full compaction ,where high strength is required . it is necessary that stiff concrete with low w/c ratio be used . to compact such concrete , mechanically operated vibratory equipment must be used . the vibrated concrete with low water cement ratio will have many advantages over the hand compacted concrete with higher w/c ratio.


HONEY COMBING

Honey combing may be caused by insufficient fine material in the mix perhaps due to incorrect aggregate grading on poor mixing . This can be can be corrected by increasing the sand and cement content of the mix and by proper mixing , placing and compaction. It can also occur due to the improper method of using

vibrator. So during using vibrator ,it is necessary to compacted the concrete properly through vibrator.

STIRRUP

A reinforcement used to resist shear and diagonal tension stresses in a concrete structural member. it binds and holds longitudinal bars of steel in position . it is used to prevent the buckling or spreading out the longitudinal reinforcement and also to prevent concrete from splitting outwards.


EFFLORESCENCE

This defect is caused because of alkalis present in brick ,when bricks come in contact with moisture ,water is absorbing them. This absorbed water dries out by evaporation from the exposed faces , and as it does so , the soluble salts it contains crystallation out on the surfaces . on drying grey or white powder patches appear on the brick surfaces .the bricks which have been saturated before their

placement .

Various methods have been used in attempts to remove efflorescence from masonry structures. It was learned accordingly, that the best way to remove these soluble salts was to brush the surface thoroughly with a stiff brush. Water, however, has been satisfactory for removing efflorescence from the face of concrete structures, since concrete is fairly well saturated with water. In fact, efflorescence in the form of alkali salts will be washed from the surface of concrete structures, if exposed to rain, over some period of time. If the coating is largely calcium carbonate or calcium sulfate, it adheres rather strongly and is difficult to remove by brushing. The practice developed in this case for masonry surfaces, has been to saturate the structure as thoroughly as possible with water, and then wash with diluted muriatic acid, followed immediately with an alkaline wash, then washed with water. The acid recommended is five (5) parts hydrochloric to one hundred (100) parts water, or twenty (20) parts vinegar to one hundred (100) parts water. The alkaline wash recommended is diluted household ammonia.

Much care must be taken in applying acid to Portland cement products. The acid will attack, not only the calcium carbonate and calcium sulfate efflorescence, but also other calcium compounds to produce


calcium salts such as calcium chloride. It is, therefore, very important to neutralize the acid before it can attack other compounds.

CURING

Curing decribed as the process of maintaining a satisfactory moisture content and a favourable temperature in concrete during the period immediately following placement ,so that the hydration of cement may continue until the desired properties are developed to a sufficient degree to meet the

requirement of service.


CONCLUSION

Though I have gathered sound knowledge regarding construction of a new building and repair, rectification and renovation of heritage building from the site of Jnan Chandra Ghosh Polytechnic, but it is indeed a rare chance to have an experience over such a sophisticated auditorium like Nazrul Mancha where all modern auditorium facilities sofisticated acoustics ,heat insulation materials like glass wool ,armaflex foam ,calcium silicate board, m.d.f board etc properly used.


Engineering

Civil construction project report at kmda