TEST RESEARCH ON MECHANICAL PROPERTIES OF STEEL FIBER REINFORCED LIGHTWEIGHT AGGREGATE CONCRETE

The experimental research on the compressive strength，split tensile strength，shear strength and flexure behaviours of straight steel fiber and indented steel fiber reinforced lightweight aggregate concrete ( SFRLAC) was conducted respectively． The mixing amount of steel fiber ranged from 0 to 120 kg /m3 ． The results show that the adding of steel fiber into the matrix leads to a little enhancement on compressive strength，while remarkable enhancement on the split tensile strength，shear strength and flexure behaviours． There are almost no difference between enhancing effect on the SFRLAC compressive strength of the straight steel fiber and that of indented steel fiber at the same mixing amount． The indented steel fiber leads the more obvious enhancement on the split tensile strength，shear strength and flexure behaviours of SFRLAC． On the section of bending failure specimen，the steel fibers were pulled out，not broken，and the ceramisite were broken，not destroyed from the interface debonding with the ceramisite． The advice of suitably increasing the tensile strength of ceramisite and decreasing the tensile strength of steel fiber is put forward to increase the performance price ratio of the SFRLAC．