Analysis On The Dynamic Response Of Concrete Filled CFRP-steel Tube Columns Under Explosive Load

Frequent explosions lead to the destruction of buildings and structures. The destructionbrought about not only huge economic losses, but also a large number of casualties. So theantiknock design, analysising the dynamic performances of buildings under explosion load,researching how to improve and strengthen the dynamic performances of the structuresbecome the urgent request. Concrete filled CFRP-steel tube columns as a new structure havehigher bearing capacity and good durability.They can give full play to the advantages of highcompressive strength of concrete under uniaxial compression, avoiding the buckling of thesteel tube. The combination of CFRP and tube can reduce the steel tube wall thickness, reducethe overall weight of structures.The cost will reduce by use them instead of high strength steel.And the combination can solve the steel pipe corrosion and the shortage of CFRP tube plasticat a certain extent. This article combining the method of theoretical analysis and numericalanalysis to analysis the dynamic displacements of concrete filled CFRP-steel tube columns. Itmainly includes the aspects show as following.The combination stiffness of concrete filled CFRP-steel tube columns were infered by CFSTunified theory. And the plastic limit bending moment of them were infered also. The maximu-m dynamic displacements were sloved on the basis of equivalentsingle-degree-of-freedomsystem through simplifing the explosive load as triangle impact load.The models of concrete filled CFRP-steel tube columns were built by using ANSYS/LS-DYNA. The concrete and steel tubes were simulated by Solid164elements while the CFRPwas simulated by Shell163elements. And the loads CFRP-steel tube columns suffered fromexplosive were simplified as descending triangle loads through applying them on one side ofthe columns. The validity of the models were proved by the comparison between the results ofnumerical analysis and that of the numerical models.The thickness of the CFRP, the ratio of the steel, the scaled distance have impacts on thedynamic performance of concrete filled CFRP-steel tube columns under explosive load. Andthe influences were analyzed by changing the parameter of the model and the explosive load.