Experimental Study On Bond Anchorage Performance Of B-PP HFRC With Steel Bar

With the rapid development of human society,the demand for diversity and functionality of concrete is becoming more and more urgent.By mixing many fibers into concrete according to specific volume rate,the strength and durability of concrete will be greatly improved.Hybrid fiber reinforced concrete is one of the most popular research topics in recent years.Basalt polypropylene hybrid fiber concrete(Basalt-polypropylene Hybrid Fiber Reinfor-).As a new type of composite material,CED Concrete,as a new type of composite material,is still in an exploratory stage that needs to be studied,but the prospect of its development still cannot be ignored by us.The application of B-PP HFRC in design engineering is bound to work with the reinforcement under the action of external load,and at the same time,it has good bond performance.Therefore,the study of bond and anchorage performance between B-PP HFRC and steel bar is one of the technical difficulties in designing and popularizing this new composite material.At present,the bonding and anchoring properties of B-PP HFRC and steel bar are rarely reported.Therefore,through theoretical analysis and experimental research,the bonding properties of B-PP HFRC are studied in this paper.(1)The orthogonal test method is used to design the test.The volume rate of basalt fiber,the volume rate of polypropylene fiber and the strength of concrete are taken as the main variables,and three horizontal parameters are set for each variable.To study the influence of slump,cube compressive strength and splitting tensile strength of B-PP HFRC on matrix concrete.The test shows that the hybrid fiber concrete can increase the splitting tensile strength of the matrix,but it has not toomuch effect on the slump and the cube compressive strength of the matrix,and even has the reverse effect.But it can obviously prevent the occurrence and development of component cracks,and improve integrity of components.(2)This paper studies the bond anchorage performance of 20 specimens through the single end central drawing test to study the influence of the volume rate of basalt fiber,the volume rate of polypropylene fiber and the strength of concrete on the matrix concrete in B-PP HFRC.The full curve of the measured load slip is recorded,the whole process of the bond failure of B-PP HFRC and the steel bar is studied,and the bond slip curve and the failure form of the member are analyzed.The optimum ratio of bond performance is given.At the same time,on the basis of summarizing the research on the theory of bond anchorage between domestic and foreign scholars,the measured data are compared with the theoretical calculation values to verify the reliability of the test.