Experimental Study On Flexural Behavior Of HRB400 Reinforced CF30 Steel Fiber Light Weight Concret T-beam

To further understand the strengthening effect of steel fiber on lightweight aggregate concrete,promoting the application of steel fiber lightweight aggregate concrete in the field of structure,this topic is based on the existing research,volume rates of steel fibers(0%,0.5%,1.0%and 1.5%)were variable,prepared the steel fiber all light concrete with matrix strength LC30(SFRaLAC),and poured 8 t-shaped test beams with a length of 4m and a height of 700mm,to carried out the bending performance test.The flexural cracking performance,crack spacing,crack width,flexural stiffness and normal section bearing capacity of t-shaped beams at different volume rates of steel fibers were investigated,the test results showed that:The addition of steel fiber improves the integrity of concrete in compression zone of SFRaLAC t-beam and the tensile performance of concrete in tension zone,changes the failure of concrete in the compression zone.Meanwhile,steel fiber improves the crack resistance,stiffness and flexural capacity of SFRaLAC t-shaped beams,it has certain inhibiting effect on the development and extension of all light concrete t-beam crack.As the volume rate of steel fiber increases,the cracking moment,stiffness and ultimate bearing capacity of t-beam increase gradually.Through comparison and analysis of test data,the formulas for calculating the effective crack height,average crack spacing and average crack width of pure bending t-beam of all-light concrete and the short-term stiffness of t-beam of all-light concrete are proposed.In this paper,on the basis of experimental data and theoretical research,to explore suitable for light all reinforced steel fiber concrete T beam formula of flexural bearing capacity is verified and the applicability of the existing specifications,applicable to steel fiber is established complete light concrete T beam bending calculation formula of maximum crack width and cross section stiffness,and compared with the test data,for the steel component in the theoretical basis for engineering application.