How many cement begs required in100 sq ft of rcc?

To determine the number of cement bags required for a 100 sq ft RCC slab, you need to consider the thickness of the slab and the concrete mix ratio. Here's a general calculation based on common practices:

1. For a 4-inch thick slab (M20 grade concrete):

   • The volume of wet concrete is approximately 33.33 cubic feet.
   • The dry volume is about 51.33 cubic feet.
   • Using a mix ratio of 1:1.5:3 (cement:sand:aggregate), the volume of cement needed is about 9.33 cubic feet.
   • Given the density of cement is 1440 kg/m³, the weight of cement required is approximately 380.4 kg.
   • Therefore, about 7.6 bags of 50 kg cement are needed2.

2. For a 5-inch thick slab (M20 grade concrete):

   • The volume of wet concrete is about 41.67 cubic feet.
   • The dry volume is approximately 64.17 cubic feet.
   • Using the same mix ratio, the volume of cement needed is about 11.67 cubic feet.
   • The weight of cement required is approximately 475.2 kg.
   • Therefore, about 9.5 bags of 50 kg cement are needed2.

For M25 grade concrete with a mix ratio of 1:1:2, the calculations would yield slightly different results, typically requiring more cement due to the higher cement proportion in the mix2.

These estimates can vary based on specific project requirements and local construction practices. It's advisable to consult with a civil engineer for precise calculations.