RCC (part2) Ready Mix concrete

hose pour slab

3. 3)  Minimum Cement Content, Maximum Water Cement Ratio and Maximum Cement Content shall be as per the requirements of IS 456:2000 with respect to the exposure conditions specified there in.
   

3. 4)  Site Engg  requirement of workability at the pump point as measured by slump test shall be between 140-160 mm, so that after pumping to the desired location the slump is minimum120 mm. Any concrete shall be designed for a minimum three hours retention/open time. The workability of the concrete shall be controlled on a continuous basis during production and any corrective action necessary taken. No additional water, other than the amount required to produce the specified grade of concrete as per mix design, shall be added to the truck mixer drum before discharge unless specifically requested and signed for representative. 
   
4. Redosing or split dosing shall be allowed subject to the written permission of trained technicians and Engineers . In any case, the total dose should not exceed the maximum dose of admixture declared by Supplier or recommended by Admixture supplier. The supplier shall stock at least 50 litre of admixture with  Quality Control department at site.
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6. 5)  Any concrete poured should get finally set within maximum 24 hours.
   
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8. 6)  Any concrete of a specified Grade shall meet the characteristic strength in 28 days. Any concrete being supplied to our site, which does not achieve minimum characteristic strength at 28 days, shall be considered as failure and no other acceptance criteria shall be entertained.
   
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10. 7)  It is important to maintain the water cement ratio constant at its correct value. The amount of added water shall be adjusted to compensate for any observed variations in the moisture contents in the aggregates. Suitable adjustments should also be made in masses of the aggregates due to this variation. Any change in water content due to change in aggregate grading shall be taken care of by forward control by suitable modifications to mix design.
    
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12. 8)  Batch sheets, moisture correction calculation/sheet shall be submitted along with challans for every pour of concrete. The scope of addition of extra admixture (over and above the quantity which has already been added at the time of batching at plant) shall be declared by concrete supplier. Immediately before discharging the concrete at the point of delivery, the producer or his representative shall provide