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Pre-stressed cement concrete


      Pre-stressed cement concrete :-  It is a cement concrete in which high compressive strength are artificially induced before its actual work. This type of concrete can take up high tensile and compressive stresses without development of crack.
Ø  Advantages:-
a)    Longer span length increases untroubled floor space and parking facilities.
b)    Thinner slabs, that are important for high rise building as with the same amount of cost, it can construct more slabs than traditional thicker slabs. 
c)    As the span length is larger, fewer joints are needed than traditional RC structures. 
d)    Because of fewer joints, maintenance cost also becomes reduced during the design life as joints are the major locus of weakness in a concrete building.
e)    Long-term Durability. 
f)     Better finishing of placed concrete. 
g)    It requires a smaller amount of construction materials. 
h)   It resists stresses are higher than normal RCC structures and is free from cracks.
Ø Disadvantage:-
a)    It requires high strength concrete and high tensile strength steel wires.
b)    The main disadvantage is construction requires additional special equipment like jacks, anchorage etc. 
c)    It requires highly skilled workers under skilled supervision. 
d)    Construction cost is little higher than RCC structures.

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