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Causes of Dampness in buildings:- Dampness generally caused by: - (a) Under Ground water (b) Rain water and (c) Leakages from plumbing pipes (a) Dampness due to Under Ground  Water:   Buildings are constructed on soils. Soil holds water for a long time. Sometimes water level may rise and come in contact with foundation. Due to capillary action moisture from ground rises into foundation, floor and even in wall. (b) Rain Water:  Entering in the building components due to various reasons. (i) From wall top:  If top of wall is not protected with impervious course like concrete, water can enter the wall and keep it damp for a long time. (ii) From face of external walls:  Splashing of outer wall by rain results into moisture entering the wall. Poor plaster coat is the main source of this type of dampness.  (iii) Improper fixing of downtake pipes:  If downtake pipes from roof are not properly fixed, a thin layer of water stagnates near the mouth of downtake pipes.  This results in

Curing of Concrete Structure: Curing of Concrete Curing may be defined as the process of maintaining satisfactory moisture and temperature conditions for freshly placed concrete for some specified time for proper hardening of concrete. Curing in the early ages of concrete is more important. Curing for 14 days is very important. Better to continue it for 7 to 14 days more. If curing is not done properly, the strength of concrete reduces. Cracks develop due shrinkage. The durability of concrete structure reduces.  The following curing methods are employed:  (a) Spraying of water  (b) Covering the surface with wet gunny bags, straw etc.  (c) Ponding  (d) Steam curing and  (e) Application of curing co (a) Spraying of water:  Walls, columns, plastered surfaces are cured by sprinkling water.  (b) Wet covering the surface:   Columns and other vertical surfaces may be cured by covering the surfaces with wet gunny bags or straw.  (c) Ponding :  The horizontal surfaces like slab and floors are