PROJECT REPORT

ON

COMMON DEFERCT

IN BUILDING

CONSTRUCTION AND

REMDIAL MEASURES

PRESENTED BY:

S.K. SHARMA XEN/BR/NWR R.MURALI AXEN/Works/SR

L.N. REDDY ADEN/SCR K.K. SINGH ADEN/NFR

IN THE GUIDANCE OF: SHRI. N.C.SHARADA Sr. PROFESSOR

IRICEN, PUNE

1. PREAMBLE

Importance of Housing Housing is an important scale of the level of country’s social progress. Besides food and clothing human’s next basic need is shelter. Shelter – they requires for protecting himself against natural calamities, wild animals and beasts and from other fellow beings. The history of mankind reveals that the man has been moulding his environment consciously or unconsciously throughout the ages. From the cave – his early abode – down to the most sophisticated air-conditioned houses of today, it is an absorbing and thought-provoking study of human’s progress and advances in various fields. House is a medium for self expression as well as a sanctuary for old age. On an average, one lives almost two-thirds of one’s life in the house. As such, ownership and utility of house contributes a lot to human welfare and joy. In India particularly, the very possession of house is regarded as a symbol of prestige and status in society. The house ownership inculcates a feeling of responsibility by society about use, poise and belonging to a community of people. Voltaire had rightly said that ownership gives personality and uplifting pride. House ownership binds one to the soil, to the community, ennobles, and creates self-confidence, dignity, a sense of responsibility, security, civic sense and stable personal behavior. It is not uncommon that to acquire this objective, the people put all efforts and hard earned savings towards this end. Housing building design which includes its internal and external environment has traditionally been the responsibility of the architect. With recent developments house building has now become so complex a task that, except for the simplest of buildings, a multi-disciplinary involvement is necessary. Internal form and environment will be determined by the functional requirements of the occupants, the space needed to meet these functional requirements and the required comfort levels in regard to such items as noise, temperature, humidity and lighting. The external form and environment depends upon the site characteristics and adjacent buildings.

Housing Organizations and Associations In India, general requirements for planning and layout of buildings have been covered by the relevant by – laws brought out by the local authorities in various big cities of different states. All these by-laws more or less follow in principle the by-laws laid down by the Indian Standard Institution in IS : 1256and the National Building Code – Part II Administration, Part III General Building Requirements, Part IV Fire Protection, Part VIII Building Services, and Part IX Plumbing Services. In India, four organizations dealing with various aspects of housing are functioning under the aegis of the Ministry of Works and Housing, namely, National Building Organisation, National Building Construction Corporation Limited (N.B.C.C). Housing and Urban Development Corporation ( H.U.D.C.O), and Hindustan Housing Factory ( H.H.F). Central Building Research Institute The Central Building Research Institute is essentially a research body set up by the Council of Scientific and Industrial Research. This National Institute was established in the year 1951. this work of the Institute is organized in seven research divisions, viz (1) Building Materials, (2) Soiling Engineering, (3) Efficiency of Buildings, (4) Building Process, Plant and Productivity, (5) Architecture and Physical Planning, (6) Fire Research, and (7) Rural Building. The last two have been added in the last. Besides these, there is also a division of information and extension to look after the research needs of the scientists and to assist in the utilization of the results of research.

2. INTRODUCTION

In Railways yearly around Rs. 1200 crore spend for the construction of New Buildings, bridges and Roads. In addition to that for maintenance of exgissiting structures lot of amount spend on every year, but proper planning, supervision, good quality of raw materials and skilled workmanship not ensured at the time of construction which leads to lot of construction defects, thus makes perennial problem to maintenance of Railway Buildings.

Practically no supervision available at the time of Building construction

work, in most of the Railway work spot, it is left to choice of contractor to choose the raw materials and to decide labour workmanship.

Most of the Labour engaged by contractor is not suitable to carry out the work, and not having adequate experience in the work entrusted to them.

Due to construction boom in private sector skilled labours are not

available in market, so forced to compromise with semi-skilled/unskilled labours.

In this Project we made small attempt to bring out the some of the most

common defects noticed in Railway Building construction works spots, it is not to find a fault in any individual but to improve the system of work and to achieve safe and maintenance free Buildings in Railways. 3. BUILDING CONSTRUCTION IN RAILWAY Indian Railways has large number of buildings for its various infrastructural needs, viz., service buildings, staff quarters, passenger amenities, etc. At present more than 7000 station buildings, many types of passenger amenities, and approximate six lakhs staff quarters are available to meet with daily requirement of about 15million passengers and 14lakhs railway employees The construction of these buildings was started at the time of introduction of railway system in India and still continued along with the extension of railway network in the India. Initially most of railway building

were constructed in stone masonry/ brick masonry in lime mortar with tiled roof or jack arch terracing etc. afterwards with the production of cement in India, construction started with stone masonry/ brick masonry in cement mortar along with RCC roof slabs. Many of the old buildings have given aesthetically pleasing look and historical heritage look as per that area and are landmarks even today. The service life of a building is expected more than 50 years with normal maintenance. Indian Railway has a big building infrastructure but no due care is being given for the building construction and their maintenance which is resulted in poor construction and quality work. We in the Railway far behind from other department as well as from open market in the building construction because very casual approach is being taken in Railway for construction/maintenance of buildings.

To look after building construction works in open line, the administrative set up are CE/Works at zonal level available, at divisional level Sr.DEN/DEN, sub-divisional level ADEN and field level SSE/SE/JE (Works) are responsible. 4. What are Construction Defects?

Although there is controversy in defining what construction defects are, normally it is grouped into four categories.

a). Design Deficiencies: Design deficiencies, which sometimes stem from the work of engineers. These design professionals design a building or design a specific system that does not function, as it was intended to function. The end result is a product that is defective.

b). Material Deficiencies: Material deficiencies are occurring by using inferior building material that causes a variety of defect. This type of defect that is fairly common is doors and windows built with poor quality materials will warping and cracking.

c). Substandard Workmanship: This category of construction defect usually becomes evident with water seepage through some part of the building structure. Other examples of such as cracks in floor slabs or in the

foundation. There could also be evidence of construction deficiencies in plumbing.

d). Subsurface or Geo-technical Problems: This issue occurs when housing developments are built in areas where water once stood, or is hilly, both resulting in an unstable foundation upon which to build a house. If foundation not did properly on this soil then inevitably it will begin to see symptoms of this construction defect.

In this project we had taken up last three defects for discussion and left design aspect deficiencies. 5. CRACKS IN THE BUILDING

Occurrence of various crack patterns in the building during construction, after completion when it is subjected to super imposed load or during the service life, is a common phenomenon. A building component develops cracks whenever the stress in the components exceeds its strength. Stress in the building component could be caused by externally applied forces, such as dead, live, wind or seismic loads; foundation settlement etc Cracks in buildings could be broadly classified as structural and non – structural cracks. Structural Cracks:- These occur due to incorrect design, faulty construction or overloading and these may endanger the safety of a building. e.g.Extensive cracking in wall and beams.

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Non Structural Cracks:- These are mostly due to internally induced stresses in buildings materials and do not endanger safety of a building but may look unsightly, or may create an impression of faulty work or may give a feeling of instability. In some situations due to penetration of moisture through them non structural cracks may spoil the internal finishes thus adding to the cost of maintenance, or corrode the reinforcement, thereby adversely affecting the stability of the Structural in long run. e.g. Plastering cracks, Vertical crack in a long compound wall due to shrinkage or thermal movement etc.

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6.PRINCIPAL CAUSES OF CRACKS

To prevent or minimize the occurrence of non-structural cracks it is necessary to understand the basic causes and mechanism of cracking, and certain properties of building materials which may lead to dimensional changes of the structural components. The principal mechanism causing non-structural cracks in the building are: a). Moisture change b). Thermal movement c). Elastic deformation d). Creep e). Chemical reaction f). Foundation movement & settlement of soil g). Growth of vegetation a) Moisture change: Most of the building material (e.g. Concrete, mortar, burnt clay brick, timber, plywood etc.,) are porous in their structure in the form or inter – molecular shrinks on drying. These movements are reversible i.e. cyclic in nature and are caused by increase or decrease in the inter – pore pressure wit moisture change. Extent of movement depends upon molecular structure and porosity of a material. Apart from reversible movement certain materials undergo some irreversible movement due to initial moisture changes after their manufacture or construction. The incidences of irreversible movement in materials are shrinkage of cement and lime based materials on initial drying i.e. initial shrinkage/plastic shrinkage and expansion of burnt clay bricks and other clay products on removal from kilns i.e. initial expansion. b) Thermal movement All materials more or less expand on heating and contracts on cooling. When this movement is restraint, internal stresses are set-up in the component, and may cause cracks due to tensile or shear stress. Thermal movement is one of the most potent causes of cracking in buildings and calls for careful consideration. The extent of thermal movement depends upon.

1). Ambient temperature variation

2).Co-efficient of thermal expansion:- Expansion of cement mortar & concrete is almost twice of the bricks and brickwork. Movement in brickwork in vertical direction is 50 % more than in horizontal direction. 3. Dimensions of components: - The cracks due to thermal movement is caused either due to external heat i.e. due to variation in ambient temperature, or due to internally generated heat i.e. due to heat of hydration in mass concrete during construction. Cracks in the building component due to thermal movement opens and closes alternatively with charges in the ambient temperature. The concreting done in summer in more liable for cracking due to drop in temp. in winter since thermal contraction and drying shrinkage act in unison. Whereas the concrete job done in the winter in less liable to cracking through it may require wider expansion joints. Generally specking, thermal variation in the internal walls and intermediate floors are not much and thus do not cause cracking. If is mainly the external walls exposed to direct solar radiation, and the roof, which are subjected to substantial thermal variation, are more liable to cracking.

c) Elastic Deformation Structural components of a building undergo elastic deformation due to dead and the super imposed live loads, in accordance with hook law. The amount of deformation depends upon elastic modulus, meningitides of loading and the dimension of the component. This elastic deformation under certain circumstances causes cracking in the building as under: -

1. When walls are unevenly loaded with wide variations in stress in different parts, excessive shear stress is developed which causes cracking in walls. 2. When a beam or slab of large span undergoes excessive deflection and there is not much vertical load above the supports (as in the case of roof slab), ends of beam / slab curl up causing cracks in supporting masonry. 3. When two materials, having widely different elastic properties, are built side by side, under the effect of load, shear stresses are set up at the interface of the two materials, resulting in cracks at the junction. Such a situation is commonly encountered in the constructions of RCC framed structure and brick masonry panel (external) and partitions (internal) walls. d) Creep: - In concrete, the extent of creep depends on.

1. Water & cement content 2. Water cement ratio 3. Temperature and humidity 4. Use of Admixture and pozzalans 5. Age/strength of concrete at the time of loading 6. Size and shape of the component Creep increases with water and cement content, water cement ratio and temperature; it decreases with increases in humidity of surroundings and the age/strength of the material at the time of loading. Use of admixtures and pozzalans in concrete increases the creep. Creep also increase with increase in surface to volume ratio of component.

IN brickwork the creep depends upon stress/ strength ratio therefore the creep in brickwork with weak mortar in generally higher. For example : For same quality of brick, creep of brick work in 1:1:6 mortar is 2 to 3 times that of bricks work in 1:1:3 mortar. Generally creep in brickwork in approx 20 to 25 % that of concrete. In brickwork it ceases after 4 months while in concrete it may continue up to a year or so, and most of creep takes place in 1st month thereafter it pace slows down. The major affect of creep in concrete is the substantial increase in the deformation of structural members, which may be to the extent of 2 to 3 times the initial elastic deformation. This deformation sometimes causes cracks in brick masonry of frame and load bearing structures. When the deformation due to elastic strain and creep occurs in conjunction with shortening of an RCC member due to shrinkage, cracking is must more severe and damaging.

e) Movement due to Chemical reaction Certain chemical reactions in building materials result in appreciable increase in volume of materials, due to which internal stresses are setup which may results in outward thrust and formations of cracks. The material involve in reaction also chemical reactions are.

Sulphate attack Carbonation in cement based materials Corrosion of reinforcement in concrete and brickwork Alkali – aggregate reaction

f) Foundation movement and settlement of soil: Shear cracks in buildings occurs when there is large differential settlement of foundation due to one of the following causes.

1. Unequal bearing pressure under different parts of the structure. 2. Bearing pressure being in excess of safe bearing strengths of the soil. 3. Low factor of safety in the design of foundations. 4. Local variations in the nature of supporting soil, which remained undetected and could not be taken care of the foundations design at the time of constructions. 5. Foundations resting in active zone on expensive soil.

Leaning PISA TOWER due to settlement

g). Growth of vegetation: -

Roots of a tree generally spread horizontally on all sides to the extent of height of the tree above the ground and when the trees are located in the vicinity of a wall, they can cause cracks in walls due to expensive action of roots growing under the foundations.

Sometimes plants take root and being to grow in fissures of walls, because of seeds contained in bird droppings. If these plants are not removed well in time, these may in course of time develop and causes serve cracking of wall. When soil under the foundations of a building happens to be shrinkable clay, cracking in walls and floors of buildings can occur following ways. Growing roots of trees cause de-hydration of soil which may shrink and cause foundation settlement, or In areas where old trees had been cut of to make way for building construction roots had be – hydrated the soil. ON receiving moisture from some sources, such as rain etc., the soil swells up and causes an up-ward thrust on a portion of the building resulting in cracks in the building.

7. COMMON CRACK PATTERNS IN BUILDINGS The commonly observed crack pattern in building can be group as, cracks in:

a). Walls, b). RCC members, c). Renderings and plasters, d). Concrete and terrazzo floors, and e). Roof terrace.

There are some method /preventive measures for repairs of cracks in

specific cases. However, main emphasis should be given on prevention of cracks, as in many cases there may be no satisfactory method of repairing the cracks after they have appeared.

a). Cracks in walls

In masonry structure i. Cracks at ceiling level in cross walls

ii. Cracks at the base of a parapet wall iii. Horizontal cracks in the topmost story below slab level. iv. Diagonal cracks in cross walls of a multi-story lead bearing structure

v. Vertical cracks below opening sin line with window jambs vi. Vertical cracks in the top most storey at the corner

vii. Vertical cracks around stair case / balconies opening viii. Vertical cracks in the side walls at the corner of long buildings

ix. Horizontal cracks at lintel / sill level in top storey x. Diagonal cracks over RCC lintels spanning large opening.

Staff quarters wall cracks

In RCC framed structures

i) Cracking of panel walls ii) Cracking of partition walls iii) Crack in free standing walls

b. Cracks in RCC members

i) In exposed members ii) Racks in RCC members due to corrosion of re-inforcement

c. Cracks in rendering and plastering

i) On masonry background ii) On concrete background iii) Cracks around door &window frames

d. Cracks in concrete and terrazzo floors i).Crazing ii) Corner cracks iii) Cracking of floor in deep fillings

e. Cracks in roof terrace

8.COMMON DEFECTS IN BUILDINGS DUE TO NEGLIGENCE-

These can be classified based on it position and it nature of construction as under:

a. Improper layout b. Improper orientation of buildings, far & setbacks c. Casual decision for foundation d. Casual decision of plinth level e. Improper construction of wall f. Construction joint between old/new wall and dissimilar structure. g. Defective RCC work. h. Improper slope of floors in rooms and bathrooms i. Cracks in the plastering. j. Breakage of wall & plastering by installation of electrical insulation. k. Improper drainage and sewage line. l. Defects in wooden doors, window and ventilators. m. Defects painting and distempering

a). IMPROPER LAYOUT: Normally layouts are given by lay men who are not technically sound and efficient. In later stage the following difficulties may arise due to defective layout of building.

i). Properly squaring of building corner. ii).Even thickness of courses in building. iii).Straightness of wall iv).Levels of the buildings. v). Gradient of the sewage live. vi).Gradient of road and connection to the main road

REMADIAL MEASURES i). Leveling instrument and theodolite should be invariably used for out of buildings, surface drainage, sewage disposal or water supply works. No work should be started be started without installing pegs and bench marks for centre lines and levels. ii). The survey instruments should be kept in proper adjustment. Supervisor should acquire the knowledge and confidence in making permanent

adjustment. The instruments including the optical parts should be kept clean. Those should be transported with almost care. b). IMPROPER ORIENTATION OF BUILDINGS, FAR & SETBACKS- Orientation of a building is defined as a method of fixing the direction of the building in such a way that it derives maximum benefit from sun air and nature. Where possible a house or buildings facing south direction is regarded to have a best orientation as sun is at low attitude in winter days. Otherwise a house should be oriented in such a direction in which wind blows for most of time during the year. Generally in hot regions. The building facing east direction is preferred to safe guard against westerly wind. In railway very casual approach is taken for orientation FAR & set backs of the building. We are simply constructing our building parallel to otherwise perpendicular railway line without giving proper attention to the orientation, FAR and set backs. REMADIAL MEASURES i). Provide proper orientation, far & setbacks based direction of sun, and wind direction. c). CASUAL DECISION FOR FOUNDATION

Very casual approach/decision is taken in the matter mentioned below- i. Arbitrary decision for depth of foundation.

ii. Visual decision for level of bottom of foundation. iii. Not uniform width of foundation. iv. Not properly leveling of foundation. v. Excess excavation of foundation in the in same place.

REMADIAL MEASURES

i. The bottom level of foundation concrete should be governed by the benchmarks, even for a simple work, such as construction of compound wall. Otherwise the longitudinal pro of the wall will become ‘snaky’ with undulating terrain.

ii. If square ness of walls in building is not achieved through proper initial setting the blunder will show up when flooring tiles are fixed.

d). CASUAL DECISION OF PLINTH LEVEL- We are deciding the plinth level casually without seeing the following points- i) Not watching the surrounding to decide the plinth level. ii) Not taking the consideration of approach road at the time, when deciding the plinth level. iii) Not watching drainage and sewage disposal in vicinity. REMADIAL MEASURES

i. Plinth level of a building should be carefully decided depending on site conditions post history of flood level and future level of the serving roads.

ii. Where plinth masonry is of brick has the super structural and has no plinth offset, there should be a groove in plastering of exterior wall. The plinth masonry thus demonstrated should receive darker colour to suppress earth-splash due to rains. This scheme will also add to the appearance of the building.

iii. If RCC belt or plinth beam is provided at plinth level it should be cast at such a distance below floor level, so that any sewer pipe called is clearly above the belt or beam. The structural designer also should remember this point.

e. IMPROPER CONSTRUCTION OF WALL - We are not giving due consideration on the following points.

i. Improper ratio of opening. ii. Plumb ness of the wall.

iii. Improper sequence of material used in masonry work. as in stone masonry bigger size stones in lower courses and smaller in upper courses.

iv. Not proper curing of the work. v. Direction of opening

vi. Not providing leveling course/ bed blocks under lintels, slabs. vii. Not staggering of joints at a particular point.

viii. Not proper bedding of stone/ bricks in the same layer. ix. Filling of gaps in between big stones by small stone/brick pieces

without properly filling of motor.

x. Not properly mixing of mortar. xi. Thick joints

No proper Bonding at wall junction REMADIAL MEASURES

i. Adequate attention should be paid while positioning the door and

window frame with respect to the width of gap, de the hinge side and deciding the direction of opening of the shutters.

ii. In tropical countries too many windows and glazing are not required. However, of there is a tendency to wear the wall by providing too much of opening. If a wall between are junctions has openings at window level totaling to more than 50 to 60% of its length, engineering of wall by RCC pillars is necessary. Further due to unfavorable positioning of openings, scene locations of masonry may get weakened. In such situations also RCC pillar may have to be provided on the openings may have to be provided on the openings may have to be repositioned. Plasters in masonry as adopted in olden days are not just for luxury or look these have structural function too.

Every civil engineer should be conversant with the principles of brick masonry design, as explained in the National Building Code. No location on the earth is free of the earthquake possibility. Careful design and construction of masonry may save many lives in future.

iii. 3. RCC bed block should be provided at the bearing of beam carrying heavy load and resting on brick wall, to avoid stress concentration, even if drawing fails to details the same.

f. CONSTRUCTION JOINT BETWEEN OLD/NEW

WALL AND DISSIMILAR STRUCTURE- i. Casual approach is being taken for joining of masonry of new

work with the old work resulted cracks in between both the work. ii. If we are constructing the main building along with the compound

wall etc. (i.e. dissimilar work) and taking the work continuously without providing construction joints the cracks will be developed due to different loading on the work.

REMADIAL MEASURES

i. Construction must be provided in between dissimilar works right from the bottom.

g. IMPROPER BONDING OF DISIMILAR MATERAIL AND AT JUNCTION OF THE WALLS- It is because of not proper bonding of masonry in super structure. Bonding is a process of arranging bricks and mortars to tie them together in a mass of brick work. It should have a minimum of vertical joints in any part of the work. It is a weak portion of brick work and should not be continuous in two successive courses. A wall having continuous vertical joints can act as independent column. Hence, in such cases, load on wall shall not be uniformly distributed and there are chances of load settlement. A more strong and durable brick/stone masonry construction must not have continuous vertical joints. It shall distribute load on a wider area and thereby minimize the tendency to settlement. At some places some vertical cracks in masonry are seen near the joints of two angled wall and near the corner of walls. At the time of construction building masonry work of one wall is taken at a time and bricks/ stone of each layer is left cantilevered outside the surface of this

wall. If these cantilever portions are not in proper line and level or not properly matched with the right angle/ any other angle walls then cracks may be appeared. REMADIAL MEASURES ii. Construction of wall on these location should be done simultaneously

on both the location iii. Proper toothing and jointing should be done j. DEFECTIVE RCC WORK –

i. HONECOMBING- If segregation takes places during concreting and mortar is separated from Grit than honeycomb may be seen and there may be leakage problem at these points. It is very harmful as the rusting on reinforcement bars may takes place.

ii. EXPOSITION OF STEEL REINFORCEMENT BARS- If the

cover in bottom surface is not properly provided or cover Block has disturbed during concreting of slab or concreting not properly poured around the reinforcement bars. Than these bars can be seen from bottom side . Exposed reinforcement bars may be rusted.

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iii. POOR WORKABLITY – If water cement ratio is not kept proper than it is harmful to concreting work. If it is less than concreting will not be workable and concreting will not flow around the

reinforcement bars. If it is more than segregation takes place than there may be chances of honeycombing and reinforcement exposition.

iv. IPROPER SLOPE- Generally No slope is provided in RCC slab and if there is any sag at centre or any other place than water is filled in these pocket resulted seepage in the Slab.

v. IMPROPER SHUTTERING: Shuttering not done with proper care and level props are supported in inclined manner without any lateral and horizontal bracing. To adjust the height of props bricks are used .Shuttering joints are not water tight.

Shuttering poles are not vertical position REMADIAL MEASURES i. Without using concrete mixer and vibrator no concreting should be

done. ii. Curing of concrete and mortar works should be ensured as

stipulated in code. iii. All slabs should be cast dense, particularly roof slab. Cover below

reinforcement rods should be ensured at all places, by providing ample cover blocks in a reliable manner.

h. IMPROPER SLOPE OF FLOORS OF ROOMS AND BATHROOMS Sometimes we see that water is stagnant in Bathrooms and tape water near water closet is flowing in Bath. It is also painful to see that discharge from Wash Basin is running in open drain in Bath room which is extremely repulsive and deplorable. It may be because of the following points.

i. Hesitating to give the slopes in the main room.

ii. Not giving proper slope in bathroom by which water is drained off regularly.

iii. Joint of the floor tiles is not proper and not in one line. iv. Improper bedding of mortar resulted as breakage of floor tiles corners. v. Proper joints are not giving in case of cement concrete-flooring and

not doing concreting in alternate bays. REMADIAL MEASURE i). Provide adequate slope in bath and toilet for easy drain out of water. ii). Slope to be providing in rooms also if is washable. iii). Proper mortar bedding under the tiles should be ensured. iv). Do floor concreting with alternate bay not to do as a whole. i. CRACKS IN THE PLASTERING - Some times minor cracks are seen in the may be small surface cracks due to weather effect. It is plastering surface. These may be isolated at some places .the different type of cracks can be seen in the building. These cracks may be because of –

i. Due to poor work men ship. ii. Due to thermo statically changes in the climate.

iii. Due to settlement in the building. iv. At the junction of dissimilar structures. v. Not proper bonding on the wall.

vi. Not uniformly of the thickness of the joints. vii. Improper curing of the wall.

viii. Not providing molding and drips. ix. Due to excessive silt in the sand. x. Due to application of plaster before completion of curing time of

masonry work. xi. Not proper mixing of mortar.

REMADIAL MEASURES i). Reference marks to given before starting plastering. ii). Background surface to be wetted properly in advance.

iii). Not to use Fine sands having more silt. l. BREAKAGE OF WALL & PLASTERING BY INSTALLATION OF ELECTRICAL INSULATION.

iv). Uniform Mortar mixing with adequate water and uniform colour. v). Ensure Curing for 14 days.. vi). Protect open surface direct from sun light.

Sometimes electrical department damage the Plastering and rectifies the same by applying Cement mortar by hand without using a trowel and finishing tools. Such Shabby works looks very odd. As a general practice, when the civil works are completed, the electrical & communication staff starts their works and damage the civil works and finished the work by unskilled people. Which looks very dirty? REMEDIAL MEASURES

i. For Electrical installations should be got prepared by Electrical branch. Concealed wiring should be planned. Casing and capping may be the next option

ii. Civil &electrical Engineers should jointly understand the location where electric supply line enters in the building

k. IMPROPER DRAINAGE AND SEWAGE LINE Generally we show the chocking of Drainage and sewage line. It may be because of not consideration of following points –

i. Not consideration of self cleaning velocity ii. Not watching of sewage disposal points before starting of work.

iii. Not providing the required slope in sewage line iv.

REMADIAL MEASURES

i. In the case of Indian water closes only orissa type pan should be used which has straight boundaries and ….. it is a good practice is lower the where the grill is loaded by a

ii. Slope of floating in bath and toilets is important. In the case of.. there should not be any open…. discharge from the parts. The pan should have any and it should join the

iii. Sun shade should not be allowed to collect water, by providing spout of large diameter at appropriate levels.

iv. Any hole or patchwork done subsequently for water supply ,sewerage or electrical work should be properly finished and cured, so that these location don’t form source for ingress of water.

v. Sunken slabs should invariably provide for bathrooms and toilets in framed structures, the beam of outer wall of toilets though which the sewer pipes emerge must be case at lower or higher level so that there is no need to make holes in the beam to pass the pipes. The structural drawings should show these details clearly.

m. DEFECTS IN WOODEN DOORS, WINDOW AND VETILATORS Freshly cut unseasoned wood are used in buildings for wooden door and window works. Wood which are not fit for woodwork, joinery also used in construction. At a time wood having moisture content up to 25% are used, which will leads to warping, bending and cracking and finally it will end up with door and windows not closing properly and gap will be there all-round between frames and shutters. Some time sap wood also used for making door and windows it is soft work portion and it will not withstand for long time ,using soft wood to be avoided. Remedial Measures

i. Use seasoned hard country wood or teakwood with moisture content less than 12%.

ii. Sapwood, cracked ring wood and soft wood not to be used. iii. Joints in wooden members should be snugly fitted, using the right

type of joints. iv. It is a good practice to nail wooden beadings around door and window

frames, so as to cover the shrinkage cracks between wood and wall. Ready- made teak wood beadings of various designs are available in the market.

v. Provide sufficient hold fast in each door frames, to hold in firm position.

n. DEFECTS PAINTING AND DISTEMPERING

SURFACE PREPARATION FAULTS:- Paint failures can result from many causes. Here, we’ll look at some of the most common caused by faults in surface preparation.

Alligatoring: Alligatoring refers to a coating pattern that looks like the hide of an alligator. It is caused by uneven expansion and contraction of the undercoat. Alligatoring can have several causes: applying an enamel over an oil primer; painting over bituminous paint, asphalt, pitch, or shellac; and painting over grease or wax.

Alligatoring .

Peeling: Peeling results from inadequate bonding of the topcoat with the undercoat or the underlying surface. It is nearly always caused by inadequate surface preparation. A topcoat peels when applied to a wet, dirty, oily or waxy, or glossy surface. All glossy surfaces must be sanded before painting. Also, the use of incompatible paints can cause the loss of adhesion. The

stresses in the hardening film can then cause the two coatings to separate and the topcoat to flake and peel.

Peeling.

Blistering: Blistering is caused by the development of gas or liquid pressure under the paint. The root cause of most blistering, other than that caused by caused by excessive heat is inadequate ventilation plus some structural defect allowing moisture to accumulate under the paint. A prime source of this problem, therefore, is the use of essentially porous major construction materials that allow moisture to pass through. Insufficient drying time between coats is another prime reason for blistering.

Blistering.

Inadequate Gloss: Sometimes a glossy paint fails to attain the normal amount of gloss. This may be caused by inadequate surface preparation, application over an undercoat that is not thoroughly dry, or application in cold or damp weather.

IMPROPER APPLICATION

It takes a lot of practice, but able to eliminate the two most common types of application defects: crawling and wrinkling.

Crawling: Crawling is the failure of a new coat of paint to wet and form a continuous film over the preceding coat. This often happens when latex paint is applied over high-gloss enamel or when paints are applied on concrete or masonry treated with a silicone water repellent.

Crawling.

Wrinkling: When coatings are applied too thickly, especially in cold weather, the surface of the coat dries to a skin over a layer of undried paint underneath. This usually causes wrinkling. Wrinkling can be avoided in brush painting or roller painting by brushing or rolling each coat of paint as thinly as possible. In spray painting, wrinkling can be avoided by keeping the gun in constant motion over the surface whenever is the trigger down.

Wrinkling.

PAINT DEFECTS

Not all painting defects are caused by the individual doing the job. It sometimes happens that the coating itself is at fault. Chalking, checking, and cracking are the most common types of product defects.

Chalking: Chalking is the result of paint weathering at the surface of the coating. The vehicle is broken down by sunlight and other destructive forces, leaving behind loose, powdery pigment that can easily be rubbed off with the finger. Chalking takes place rapidly with soft paints, such as those based on linseed oil. Chalking is most rapid in areas exposed to sunshine.

Checking and Cracking: Checking and cracking are breaks in a coating formed as the paint becomes hard and brittle. Temperature changes cause the substrate and overlying paint to expand and contract. As the paint becomes hard, it gradually loses its ability to expand without breaking. Checking consists of tiny breaks in only the upper coat or coats of the paint film without penetrating to the substrate. Cracking is larger with longer breaks extending through to the substrate. Cracking generally takes place to a greater extent on wood, due to its grain, than on other substrates. The stress in the coating is greatest across the grain, causing cracks to form parallel to the grain of the wood. Checking and cracking are aggravated by excessively thick coatings that have reduced elasticity. Temperature variations, humidity, and rainfall are also concerns for checking or cracking.

Severe Checking Severe Cracking.

o. OTHER PRECAUTIONS

i. For new building drawing should be prepared to details the scheme of root dia and the positioning of down pipes

ii. Access to open terrace should be made available should be made

available in all buildings by providing reliable service ladders, in case extended staircases ac not exist. This is to enable engineering staff to clean and to attend to bad spots in weathering course. This will be a positive step to avoid leakage problems.

iii. It is a bad practice to leave the droppings of cement mortar on the

floor, sun and open terrace and allow them to set permanently. This leaves a poor impression of the engineers in the minds of the building users.

9.CONCLUSIONS &SUGGISIONS: From the above it has been seen that defects are non-structural cracks and majority of common defects are due to negligence of Engineers. Also proper supervision available in most of the woks spot.

In Railway supervision of building construction is left to field staff i.e SSE/SE/JE (Works) since higher officials are busy in their office and track work and building works are totally neglected. The field supervisors of open line are also busy with their regular Building, bridge and road maintenance work, routine inspections, and staff matters. Some of the supervisors are also not having adequate technical knowledge about building works.

The present system of supervision will not help to improve the defect free construction and also it will reduce the maintenance burden and cost.

Some specialized training/courses in building construction, modern materials and in foundation Engineering may be arranged for from field level supervisor to Divisional Engineer level. The higher officials are afraid to exercising the power of deciding the type and depth foundation based on the site condition.

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