concrete tech

  Anti- Termite(AAT) Chemical treatment of soil for the Protection of building form attack by subterranean termites . its include reference to the chemicals to be used, lays down minimum rates of application for usage and out line Procedures to be followed while The building is under construction.  IS CODE IS 6313 (part2) for ATT using procedure location of the structure  IS 8944 For Tasting  Pre - Construction Soil treatment        This is the process in which soil treatment is applied to a building during the early stage of its construction. Site Preparation   The removal of trees, stumps, logs or roots form a building site reduce the hazards form subterranean termites. Similarly the subfloor area should be kept free form all debris in which a new colonies of termites might be established. in Order to ensure uniform distribution of treating solution. Basic Principle     Chemical toxic to subterranean termites may be used effectively to check termite infestation in the soil these are

  DE shuttering Period As per IS 456 About De shuttering  While the above criteria of strength shall be the guiding factor for removal the form work ,in normal circumstances where ambient temperature does not fall bellow 15'C where ordinary Portland cement is used and adequate curing is done , following striking period may deem to satisfy the guide line given bellow. Vertical form work to column, wall and beam de shuttering form work is 16-24 hours. Soffit form work to slabs De shuttering form work striking is 3 Days.(props to be refaxed immediately after removal of form work ) Soffit form work to beams De shuttering form work Striking 7 Day's (Props to be refixed immediately after removal of form work) Props to Slab Props to beam and arches    Spanning up to 4.5m De shuttering 7 Days  Spanning over 4.5m De shuttering  14 days        6. Props to beam and arches  Spanning up to 6m De shuttering 14 Days.  Spanning over 6m De shuttering 21 Days             For other cements and lo

 Unit Weight of Steel calculation  steel unit weight meaning 7850 kg /m3 Volume calculation volume =𐍀/4 x d2x7850x one meter cutting length or d2/162 Nominal size of steel 4mm,5mm , 6mm, 8mm, 10mm, 12mm, 16mm , 20mm, 25mm, 32mm, 40mm. Steel per meter length  6mm =d2/162 = 0.222 kg 8mm =d2/162=0.395 kg 10mm = d2/162=0.617 kg 12mm = d2/162 = 0.888 kg 16mm = d2/162 = 1.58 kg  20mm = d2/162 = 2.46 kg 25mm = d2/162= 3.85 kg 32mm = d2/162 = 6.32 kg 40mm = d2/162 = 9.88 kg Full length weight of steel (one road maximum 12 m length) 6mm =d2/162 = 0.222 x 12 =2.64kg 8mm =d2/162=0.395 x 12 =4.74 kg 10mm = d2/162=0.617 x 12 =7.40 kg 12mm = d2/162 = 0.888 x 12 =10656kg 16mm = d2/162 = 1.58 x 12= 18.96 kg 20mm = d2/162 = 2.46 x 12 = 29.52 kg 25mm = d2/162= 3.85 x 12 = 46.2 kg 32mm = d2/162 = 6.32 x 12 = 75.84 kg 40mm = d2/162 = 9.88 kg = 118.56 kg Tolerance factor of Steel  U p to 10mm +- 8 percent 10mm to 16mm +- 6 percent above 16mm +- 4 percent IS code For Steel testing IS Code 1786 For sample t

 Slump Test concrete value Workability concrete  The concrete mix proportion chosen should be such that the concrete is of adequate workability for the placing condition of the concrete can be properly  Size of slump cone:-  slump cone lower side diameter 200mm and upper side diameter 100mm and height is 300mm  Instrument requirement :- Slump cone and tempering rod and towel and GI ghamela   Slump for placing condition divided into five type as per IS 456 Very low slump low slump Medium slump high slump very High slump 1.Very low slump:- It is very low category of workability where strict control is necessary for example pavement quality concrete ,measurement of workability by determination of compacting factor will be more appropriate than slump and a value of compacting factor of 0.75 to 0.80 is suggested  this type of concrete is use in Blinding concrete shallow section pavement and pavers block and pavers tiles. 2.Low Slump:- Mass concrete lightly reinforced section in slab ,beam ,