Experimental Study On Bonding Performence Of All-lightweight Shale Ceramsite Concrete And Reinforcement

All-lightweight shale ceramsite concrete and reinforcement work together is basis on bonding between concrete and the reinforcing bar.The bond is composed of complex stresses,which is by different constraints,the thickness of the protective layer,the length of the anchor,the type of reinforcement,the impact of factors and so on.Due to the discrete of concrete materials,the accuracy of the test methods,it is only possible to obtain the corresponding empirical formula by the tests,and still lack of theoretical system.For example,the commonly use axial pull-out test and the central pull-out test methods,Due to the actual state of the engineering with a large difference between the force,result in a large deviation.In order to eliminate this deviation,this paper compares the two kinds of test methods by beam test and pull-out test,and carries on the theoretical analysis through the related physical mechanics models.Specifically,the main research contents are as follows:(1)Based on the pull-out test,use different parameters of reinforced concrete specimens to explain the adhesive force between crescent ribs and all-lightweight shale ceramsite concrete mainly originate from mechanical bite force between crescent ribs and concrete,and give the contribution rate definition of mechanical interaction;(2)According to the typical ?-S curves of ordinary concrete,obtain the ?-S fitting curves for all-lightweight shale ceramsite concrete.According to the characteristics of the crescent ribs,come up with the model of the bond-slip model and educe bond-slip model of different stress stages,and be verified by the experimental results.(3)Analyze the characteristics of pull-out failure and its energy change process by energy angle,and put forward a new method to standardize the reinforced-concrete structure by energy method;(4)Through evolution analysis of the physical geometric model,respectively,give the different steel rib models,and put forward and then calculation ?,and gives the best model of deformed steel rib;(5)F-S curves,F-? curves and the steel strain distribution curves are obtained by beam test,and the contribution rate of section size is defined.The constitutive relation of the bond-slip action between all-lightweight shale ceramsite concrete and the steel bar is given by the beam test.(6)The two methods of bond bewteen all-lightweight shale ceramsite concrete and reinforcement are used to compare and analyze the advantages and disadvantages.