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Showing posts from July, 2020

What is the purpose of keeping tremie pipe’s tip immersed in freshly-placed concrete for about 1m in underwater concreting?

  What is the purpose of keeping tremie pipe’s tip immersed in freshly-placed concrete for about 1m in underwater concreting? The size of tremie pipe is about 300mm with sections having flange couplings fitted with gasket to prevent water leakage. The tremie pipe should be closed initially to prevent water from entering the pipe. It should be designed with sufficient thickness and weight so that it would not be buoyant when empty inside water. The placement of tremie concrete is commenced by putting the closed pipe underwater to the location for concreting, followed by partial filling of tremie pipe with concrete. In order to have tremie concrete flowed out of the pipe, it is necessary to fill the pipe with concrete of sufficient height to overcome the water pressure and frictional head. After that the tremie pipe is raised about 150mm to allow concrete to flow out. To enhance sufficient bonding, each succeeding layer of concrete should be placed before the preceding layer has reached
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what are the differences between epoxy grout, cement grout and cement mortar??What is the difference between foam concrete and cement grout?

differences between epoxy grout, cement grout and cement mortar Epoxy grout In fact, there are various types of resin used in construction industry like  epoxy, polyester, polyurethane etc. Though epoxy grout appears to imply  the presence of cement material by its name, it does not contain any  cement at all. On the other hand, epoxy hardener serves to initiate the  hardening process of epoxy grout. It is commonly used for repairing  hairline cracks and cavities in concrete structures and can be adopted as  primer or bonding agent. Cement grout ratio of cement of water is more or less similar to that of concrete.  Owing to the relatively high water content, the mixing of cement with water  produces a fluid suspension which can be poured under base plates or into  holes. Setting and hardening are the important processes which affect the  performance of cement grout. Moreover, the presence of excessive voids would also affect the strength, stiffness and permeability of grout. It is  ver
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WHAT IS THE MAIN PURPOSE OF PILE LOAD TEST ??

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Purpose of Pile Load Test. Pile foundations are designated for load tests more frequently in comparison to other foundation  units for two main reasons: 1) The inability to visually inspect the pile after installation and 2) The limited understanding of the material surrounding the pile. It is evident that the design and  construction of pile foundations involve numerous factors and potential problems, most of which  originate from the occurrence of defects in the load bearing pile body itself or its surrounding  soil material to which the load is transferred. Conducting load test compliment the pile foundation design and construction practice through provision of vital information regarding the pile-soil system particular to a combination of pile type, installation method and site condition. The load test is conducted either for investigation or confirmative purpose. Initial Load Test: The initial load test is required to be carried out for following purpose: a) To study the load sett
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what is bored cast in situ piles ?? step by step procedure.

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CAST-IN-SITU BORED PILES This topic provides basic Guidelines in case of cast in situ piling works, few points to be taken care of and things which can go wrong on-site during execution. Cast-in-Situ bored piles, as we all know, are constructed by various techniques: a) Using permanent casing. b) Using temporary casing. c) Using bentonite and chisel bailer boring. d) Using bentonite with direct mud circulation or reverse mud circulation or e) The pile may be bored by Rotary method using Rotary piling rigs. Today, when water is present in the bores, piles are concreted by use of tremmie pipes which is the  standard technique and acceptable to all. In and around the Mumbai area, the average length of piles is generally around 10 metres and most  contractors make use of temporary casing of 16 mm thickness driven into the bores upto noncollapsible  strata in order to stabilize the bores and prevent collapses. If these casing are driven up to  non-collapsible strata and boring is continued
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PAVER BLOCK.WHAT IS THE PROCEDURE FOR PAVER BLOCK FIXING ?? W.B.M (WATER BOND MACADAM)

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Paver blocks.   1-     Study the Arch drawing and services drawings to find out levels, and gradient of road. Paver block typical section is as shown below. Details can change depending on strata and vehicular loads.   2)   Every lot of paver blocks shall be tested to confirm strength as per requirements.   Preparation of Subgrade 3.1)  Cutting/filling of subgrade to required level, gradient and camber. 3.2)  Carry out lime stabilization treatment for sub base as per specifications given below.( Where ever specified ). 3.2.1) Excavate up to required level & Gradient. 3.2.2) Loosen the soil up to 200 / 300 mm below the required level preferably with JCB / Tractor having Pulversing tool attachment. 3.2.3) Spread the lime over the loose soil @ 5kg / sq.mtr. and mix the lime and soil by using spade and sprinkle water over it. 3.2.4) No traffic should be allowed to move over it other than the mixing equipments till mixing is complet
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WHAT IS THE STANDARD HEIGHTS FOR ELECTRICAL POINTS??

Standard Heights for Electrical Point The standard heights for electrical points to be provided at the below given heights in the flats: a) Bracket Light: 2200 mm above SFL (Except for kitchen; light point above main door & light point above window - where it shall be 2600mm) b) Switch boards near doors: 1200 mm above SFL. c) (i) 5A plug point: 625 mm above SFL.     (ii) 15A power plug point: 625 mm above SFL .(except AC points)     (iii) Bed side switch board: 700 mm     (iv) All Bed side points: 700 mm d) Telephone/Intercom point: 625 mm above SFL. e) TV Antenna/Cable TV: 625 mm above SFL. f) Distribution Board: 1600 mm above SFL. g) Door bell switch: 1200 mm above SFL. h) Heater connector : 2210 mm above SFL of toilet. i) Heater Indicator (switch): 1200 mm above SFL. j) Bell: 2500 mm above SFL k) BKT light , above wash basin/counter in toilet: 25 mm below bottom of loft or 1950 mm above FFL of toilet. l) 15A for A/C in living room / bedroom.: 15A plug point with 25
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WHAT IS FIRE FIGHTING SYSTEM ??WHAT IS THE CFO REQUIREMENT FOR BUILDING

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Fire Fighting system To begin with, FIRE is one of the five elements of Nature. As such, FIRE is omnipresent and is also known to be omnipotent. FIRE in the form of flame & heat is not only essential for the sustenance of  life but has also enormously contributed to the progress, prosperity and comforts of human race. Nevertheless, FIRE also has its destructive side. FIRE kills people & destroys property – the two most precious things for a human being. It is common knowledge that FIRE has destroyed the art, architecture and history over the centuries, bringing in its wake destruction and distress to human race. Obviously, it is the duty of one and all of us to prevent fires and minimize the life and property losses. • Fire fighting system required in the commercial or high rise buildings are as per the  requirement of the CFO ( Chief Fire Officer)  a) Hydrant system  b) Sprinkler system  c) Alarm system a) Hydrant system: 1) Main Fire Pump [ Design pressure 3.2 Kg/cm2 at topmo
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