Quality Assurance Handbook for Rural Roads Volume-I - pmgsy

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Quality Assurance Handbook for Rural Roads
a 3 m straight edge, rake open the area and add extra material or remove extra material. Check the
in-situ density by sand replacement method and if field density is less than 97% of the trial length,
use additional passes of roller to achieve at least 97% of density of trial length.
15. The final time of rolling shall not exceed 100 minutes from the time of mixing water when the
temperature is between 25 0 C and 30 0 C, and 120 minutes when the same is less than or equal to
25 0 C. No concreting is to be done when the temperature is less than 4 0 C or more than 40 0 C. Chilled
water should be used to bring the temperature of concrete to 30 0 C. Take precautions indicated in
IRC:15 when ambient temperature is below 5 0 C or more than 40 0 C.
16. Carry RCCP over hume pipe culverts. In case of existing or new bridges/ culverts, RCCP shall
abut the deck/ approach slab and a construction joint should be provided.
17. No longitudinal joint shall be provided if the width of carriageway is less than 4 m. RCCP shall
have only transverse contraction joints at 5 m center. These shall be saw-cut after 6-12 hours of
laying or initial hardening. The width of joints shall be 6-8 mm and depth one-fourth of RCCP
slab. These shall be filled with hot pouring sealing compound in accordance with sub-section
1501.22.4 of MORD Specifications and in accordance with IS:1834.
18. Cover RCCP, within one to two hours after compaction, by laying wet hessian in two-three layers
for first 24 hours. After the first day’s curing, small earthen rectangles/ dykes about 50 mm high
transversely and longitudinally shall be made and filled with water for at least 14 days. In case of
flyash concrete, the period shall be 16 days.
19. Freshly laid RCCP shall be protected by not allowing traffic for a minimum period of 28 days.
B. Quality Control Requirements
1. Material
Cement, Water, Coarse and Fine aggregates for roller compacted concrete shall meet the
requirement of material indicated in Section 1501 B, except that the grading of blended coarse and
fine aggregates shall be in conformity with the requirements indicated in Table No. 1502.2.
TABLE 1502.2: AGGREGATE GRADATION FOR RCCP
IS Sieve designation Percentage passing by weight
26.5 mm 100
19.0 mm 80-100
9.5 mm 55-75
4.75 mm 35-60
600 micron 10-35
75 micron 0-8
Fly-ash may be from anthracitic coal or lignite collected by electro-static precipitator. Bottom ash
or pool ash shall not be used as a replacement of cement. Flyash shall conform to the physical
requirements indicated in Table No. 1502.3.