Summary of Important Control Procedures

1. As far as possible use cement from one source 
2. Keep the coarse aggregate in sewate sizes and recombine them in correct proportions at the time of batching. 
3. make regular grading test for coarse and fine aggregates and as and when necessary  adopt corrective measures. 
4. As far as possible batch  all  materials by weight.  
5. Maintain regularly the batching devices and check on their calibration. 
6. Maintain stock-piles of aggregates sufficient, at any one time, for at least 24 hours. Stock-piles should be flat topped and not conical, to prevent segregation. 
7. Determine moisture contents of aggregates, at intervals. 
8. Conduct slump test regularly. If the mix is tot) dry (slum less than 4 cm) compacting factor test should be used. 
9. Check transport  and handling arrangements for arresting any  tendency to segregate. 
10. Adjust the quantity of water at the mixer for maintaining proper water/cement ratio. 
11. Check on mixing  time,  revolutions of the drum, quantity of the charge and mode of unloading the mixer. 
12. Place concrete inside the formwork from  a height so as not to cause segregation and as near as possible to its final position. 
13. Check regularly on the walking of the vibratory acre  s and internal vibrators and their mode of operation. 
14. Compact concrete in multiple layers, when the thickness is more than 20 cm (8 ins.) 
15. Curing should be qroperly done for at least 14 days.