Civil Engineering - Building Materials - Discussion

What is lime pozzolana cement and where is it used?

A pozzolan is an siliceous or siliceous and aluminous material which, in itself, possesses little or no cementitious value but which will, in finely divided form and in the presence of water, react chemically with calcium hydroxide at ordinary temperature to form compounds possessing cementitious properties.

Why its takes to more initial setting ? Please explain me or what is the reason?

What is the final setting time to this cement?

Initial setting time of OPC is 90 min.

Initial setting time of OPC is 30 min.

Initial setting time OPC cement is 30 min it is correct answer.

Initial setting time is 30 min is correct answer.

Pozzolana take that much time because as it contain silicate it react with lime to form c-s-h gell. But it a slow reaction process. While on the other hand cement react with h2O to form a solid structure.

STANDARD SPECIFICATION:

Type/Name Of Cement, Referenced Indian Standard, Initial Setting Time, mints (min), Final Setting Time, mints (max).

OPC(33), IS:269, 30, 600.

OPC(43), IS:8112, 30, 600.

OPC(53), IS:12269, 30, 600.

SRC, IS:12330, 30, 600.

PPC, IS:1489, P1, 30, 600.

RHPC, IS:8041, 30, 600.

PSC, IS:455, 30, 600.

High alumina, IS:6452, 30, 600.

Super sulphated, IS:6909, 30, 600.

Low heat, IS:12600, 60, 600.

Masonry cement, IS:3466, 90, 1440.

IRS-T-40, Railway, 60, 600.