Hi,
I will like to get some clarification regarding M15 concrete to IS 456-2000 table 5 and table 9 in terms of WC ratio. If I use the widely used 1:2:4 proportion for M15, the cement content will be 1/7x1x1440=205kg/m3 while the table minimum cement content (table 5) is 240 kg. Lets therefore use the code minimum cement content of 240 kg with a max. W/C of 0.6 .: 144 liters. There is also the max. quantity of water per 50 kg bag of cement which is 32 liters which gives us a maximum water content of 153 liters which gives a W/C ratio of 0.64 which exceeds the maximum W/C of 0.6 Lets therefore use the limiting W/C ratio of 0.6 or 144 liters.
Back to table 9, the maximum aggregate content (FA + CA) for M15 is 330 kg.
Per 1 m3 - Using 20 mm. aggregate (1:2)
240 kg of cement - 144 liters of water - 110 kg of fine aggregate and 220 kg of coarse aggregate
Per 1 m3 - Using 10 mm. aggregate (1:1.5)
240 kg of cement - 144 liters of water - 132 kg of fine aggregate and 198 kg of coarse aggregate
Per 1 m3 - Using 40 mm. aggregate (1:2.5)
240 kg of cement - 144 liters of water - 94 kg of fine aggregate and 236 kg of coarse aggregate
I will like to confirm if I have well understood how M15 concrete is to be proportioned according to IS 456:2000 or is there more to it?
I will like to get some clarification regarding M15 concrete to IS 456-2000 table 5 and table 9 in terms of WC ratio. If I use the widely used 1:2:4 proportion for M15, the cement content will be 1/7x1x1440=205kg/m3 while the table minimum cement content (table 5) is 240 kg. Lets therefore use the code minimum cement content of 240 kg with a max. W/C of 0.6 .: 144 liters. There is also the max. quantity of water per 50 kg bag of cement which is 32 liters which gives us a maximum water content of 153 liters which gives a W/C ratio of 0.64 which exceeds the maximum W/C of 0.6 Lets therefore use the limiting W/C ratio of 0.6 or 144 liters.
Back to table 9, the maximum aggregate content (FA + CA) for M15 is 330 kg.
Per 1 m3 - Using 20 mm. aggregate (1:2)
240 kg of cement - 144 liters of water - 110 kg of fine aggregate and 220 kg of coarse aggregate
Per 1 m3 - Using 10 mm. aggregate (1:1.5)
240 kg of cement - 144 liters of water - 132 kg of fine aggregate and 198 kg of coarse aggregate
Per 1 m3 - Using 40 mm. aggregate (1:2.5)
240 kg of cement - 144 liters of water - 94 kg of fine aggregate and 236 kg of coarse aggregate
I will like to confirm if I have well understood how M15 concrete is to be proportioned according to IS 456:2000 or is there more to it?
