The Research On Seismic Performance Of Timber-Concrete Composite Beams Under Low Cyclic Reversed Loading

As a new structure type,timber-concrete composite structure is developed from of concrete structure and wood structure.Timber-concrete composite beams are made of concrete slabs and timber beams,that connected by shear connections.The advantages of both materials can be used.Because bending and tensile forces are resisted primariy by the timber and compression by the concrete.Compare with reinforced concrete beam,the timber-concrete composite beams are environment.The stiffness and strength of timber-concrete composite beamsare greater than that of wood beam.So timber-concrete composite beams has application prospect.In this papera a finite element analysis model of timber-concrete composite beams has been established with ANSYS,and calculated the seismic performance under the the low reversed cyclic loading.The effect of concrete strength and joint spacing on the seismic performance of timer-concrete composite beams has been analyzed.The main results are as follows:(1)Consider different way to hand connections,establishing finite element analysis models of timber-concrete composite beams under the static load.And the numerical analysis results were compared with the test results.The results show that the load-displacement curve of finite element numerical simulation are consistent with the experimental results.(2)This paper adopts the elastic cohesive layer to simulate the bolts,which can not only effectively simulate the effect of bolts,but also the cracking of concrete can be considered in this modle.So this model can be used to simulate the hysteresis performance of timber-concrete composite beams.(3)The hysteresis loop of timber-concrete composite beams are relatively full,with good ductility and energy dissipation capacity,and good seismic performance.(4)Through the analysis and comparison of seismic performance indicators of wooden beams,reinforced concrete and timber-concrete composite beams.Founding that wooden beams have good seismic performance,followed by,timber-concrete composite beams,the seismic performance of reinforced concrete beam is poorer.Therefore,the timber-concrete composite beams not only have higher bearing capacity,but al-so have good seismic performance,which is a new type of component with superior performance.(5)Based on the seismic performance parameter analysis of timber-concrete composite beams found that with the increase of concrete strength,the displacement ductility coefficient of timber-concrete composite beams decreases,and the energy dissipation capacity is worse.With the increase of bolt spacing,the displacement ductilitycoefficient of timber-concrete composite beams increases,and the energy dissipation capacity increases.The influence of the distance between the connecting pieces on theseismic performance of timber-concrete composite beams is greater than that of concrete strength.