particular specifications (road works) - CIDCO Maharashtra Ltd.

CIDCO OF MAHARASHTRA LTD
C.A.No.01/CIDCO/SE(KHR)/EE(KHR-I)/2010–11 Pg. No. 371
The supports should be arranged in a manner that will permit the
proper finishing and curing of any in-situ concreting and grouting
associated with the precast member being supported when the gaps of
joints have to be cleaned, the faces of the joints should be wetted. The
mixing, placing and compacting of cement and mortar should be done
with special care. Where mortar is specified, or a dry consistency, it
should be in the proportion of 1 part of cement to 1 ½ parts of sand
and should be placed in stages and packed hard from both sides of the
joint.
5.22.3 Tolerances :
The following tolerances apply to finished precast products at the time
of placement in the structure. The forms must be constructed to give a
casting well within these limits.
1. Overall dimensions of members should not vary more than + 6
mm per 3 m length with a maximum variation of + 20 mm.
2. Cross-sectional dimensions should not vary more than the
following:
+ 3 mm for sections less than 150 mm thick.
+ 4 mm for sections over 150 mm and less than 450 mm.
+ 6 mm for sections over 450 mm to 1000 mm.
+ 10 mm for sections over 1000 mm.
3. Deviation from straight line in long sections should not be more
than + 6 mm up to 3 m, + 10 mm for 3 m to 6 m, + 12 mm
for 6 m to 12 m.
5.23 Mode of Measurement (For Precast Items) :
Concrete and reinforcement shall be paid separately unless otherwise
specified.