Simulation of Structural Collapse with Coupled Finite Element-Discrete Element Method

Structural progressive collapse is a great threat to life safety and therefore it is necessary to study its mechanism in detail. Numerical simulation is significant to study the whole process of progressive collapse in structural level. Since collapse is a complicated procedure from continuum into discrete fragments, numerical model should be competent in nonlinear deformation before collapse and breaking and crashing of fragments after collapse. Coupled Finite element-discrete element method on simulating structural progressive collapse is proposed to meet the requirements. Relatively accurate models, such as fiber model and multi-shell shell model, are introduced to construct the finite element model of structure. In the analysis, the failed finite elements will be removed and replaced with granular discrete elements according to the criteria of equivalent total mass and volume so that the impacting and heaping of fragments can be taken into account. The sample with the coupled method shows that this method not only possesses the advantages of finite element method but also simulates the behavior of fragments well.