Experimental Analysis Of Bond Property Between Light-Weight Ceramsite Concrete And Steel Bar

As lightweight concrete,ceramsite concrete has a lower dead weight than ordinary concrete,and can be used in building structures to reduce the weight of the structure to a large extent,thus improving the seismic performance of the building.In addition,ceramsite concrete has better durability,strong corrosion resistance and fire resistance than ordinary concrete.Ceramsite has a wide range of sources,and a large number of industrial wastes can also be used as raw materials for the production of ceramsite,which can greatly improve the economic performance of buildings.But at present,the use of ceramsite concrete in load-bearing structure is relatively less,so there is a long way to go for the study of ceramsite concrete on load-bearing structure.The reinforcement and ceramsite concrete have good bonding performance on the premise that the reinforcement and ceramsite concrete can work together.This paper aims at the application of lightweight ceramsite concrete in load-bearing structures.Starting from the bond theory of reinforced concrete,the drawing test of ceramsite concrete with a density of 1800kg/m³and a strength of C30 is designed and completed.The influence of different influencing factors on bond anchorage performance is studied.In this paper,the anchoring length,the diameter of steel bar and the thickness of the protective layer of concrete are selected as the influencing factors,and the structural analysis and calculation method of the anchoring length of lightweight ceramsite concrete is given to get the calculation value of the anchoring length.（1）The results show that the bulk density of ceramsite concrete can be successfully reduced to 1800kg/m³while the strength of ceramsite concrete meets C30.（2）The drawing test was designed to study the influence of different influencing factors on the bonding properties;The following conclusions can be drawn:1)the bond stress between LWPC and reinforcement increases with the increase of the thickness of the protective layer,and the increase of the bond stress has a linear relationship with the relative thickness of the protective layer C/D;2)With the increase of anchorage length,the bond stress of steel bar and light ceramsite concrete decreases;3)The bond stress between lightweight ceramsite concrete and steel bar decreases with the increase of steel bar diameter.（3）The test simulation was conducted by ABAQUS,and it was found that the simulation and the test had a high degree of fit,which could accurately simulate the effects of different influencing factors on the bond properties.（4）After processing and fitting the test data,the formula for calculating the bond stress is as follows:τ_u=（0.55+3.1d/l_a）(3.75+0.7c/d+18ρ_sv)f_ts（5）Calculate the bond strength between lightweight ceramsite concrete and steel bar by JC method and approximate method,and get the anchorage length of steel bar in lightweight ceramsite concrete is recommended to be 18d.