The Experimental Research of low strength Concrete Considering Strain Rate under Uniaxial Compression

The tests were implemented in low strength concrete with four kinds of strength (C20, C25, C30, C35) and with diffrent strain ratses (10-5/s-1, 10-4/s-1, 10-3/s-1 and 10-2/s-1. The stress-strain curves, strength, elastic modulus and Poisson's ratio are studied in different strain rate. The results show that: (1) With the increase of strain rate, the inflexion strength and ultimate strength of concrete were improved; (2) With the increase of strain rate, the static and dynamic elastic modulus increased slightly; (3) Poisson's ratio increased slightly with the growth strain rate. This conclusion is very important in civil engineering.