It analyzes causes of cracks of cast-in-place floor from concrete maintenance、inside and outside surface temperature control、foundation reinforcing and expansion joint,and introduces relative prevention measures to improve entirety、anti-non-uniform sedimentation and safety of house.

Based upon analysis of concrete maintenance, mould stripping, defects remedying and quality test, practical operation is introduced in this paper, which made the concrete construction meet the codes requirements and resolve the pre quality control and test issues in construction.

Study on factors effecting early mechanical properties of steam-cured concrete;

Experimental study on compressive strength and freeze-thaw resistance of steam curing concrete;

This paper mainly studied the influence of the amount of fly ash and water to binder ratio on the compressive strength,the tensilesplitting strength and the flexural strength of the steam curing concrete.

The experimental results indicate that the addition of ultrafine fly ash slag composite improves the long term mechanical properties of steam curing concrete.