Use Cement & Flay Ash (3:1) Ratio Add Non shrink Grout CBEX 100 (Or) Master Flow 150 (250grms/Bag). Mix paste to required consistency paste level. Use Rubber/PVC Moulds(50Nos/Mould), for Multipurpose in Size (Column, Slab, Beam) and use Table vaibrators for Casting the cover Block.One Mason and one helper can cast Quality Cover blocks 1000- 2000 Nos /day. Also we can use Dust Collector Cement for Cover blocks casting we can add cement if fly ash content is more in the Dust collector in RMC Plants.Grade will be M40.