钢管混凝土柱-钢梁组合框架在爆炸荷载作用下的破坏模式分析

Failure Mode Analysis of the Composite Frame of Concrete-filled Steel Tublar Column and Steel Beam under Blasting Loading

以采用外环板式节点的圆钢管混凝土柱-钢梁组合框架为研究对象,运用ANSYS/LS-DYNA模拟了组合框架在爆炸荷载作用下的破坏过程,分析了组合框架的破坏形式以及炸药当量和楼板对破坏的影响.结果表明:该种组合框架破坏的根源在于钢梁在爆炸冲击荷载作用下产生了很大的屈曲变形,导致节点处受拉破坏;随着炸药当量的增大,板出现冲切破坏,梁由弯曲破坏变为弯曲剪切耦合破坏;混凝土楼板可以损耗爆炸冲击波能量,约束梁、柱的变形,提高结构的整体性.

With the composite frame of circular concrete-filled steel tubular column and steel beam with external diaphragm joints,this paper simulates the failure process of the composite frame under blasting loading by ANSYS/LS-DYNA,then analyses the damage form of the composite frame and the effect of the explosive equivalent and floor slab on the damage.The results show that the failure of the composite frame is caused by the large buckling deformation of the steel beam under the impact of the explosive load,which leads to the tensile failure of the joints.With the increase of the explosive charge,punching and cutting appear on the floor slab,and the beam changes from bending failure to the bending shear coupling failure.The concrete floor can consume the energy of blast shock wave,restrain the deformation of beam and column,and improve the integrity of the structure.