Research On Progressive Collapse Mechanism And Prevention Methods Of Spatial Lattice Structure

In recent years, natural disasters occur frequently. Buildings are always subjectedto the threat of storm and heavy snow. Because of the wide applications and specialfunction, progressive collapse of spyramid space truss structure happen when randomevent occured will impact heavily on the social production and people’s life andproperty safety. Therefore, study on progressive collapse resistance of pyramid spacetruss structure has great significance and far-reaching influence.Resisting progressive collapse research of pyramid space truss structure mainlyincludes two aspects:(1) Whether the existing spyramid space truss structures have enough capacity ofresisting progressive collapse when unexpected events occur;(2) How to use scientific and reasonable design methods to prevent progressivecollapse of pyramid space truss structures.This article explored progressive collapse mechanism of pyramid space trussstructures under the combination of finite-element analysis and experiment on thepremise of important element failure and studied three core issues as follows:(1) Rearsch on the methods for evaluating the significance of pyramid spacetruss structure members;(2) Study on progressive collapse mechanism of pyramid space truss structurebased on important components failure;(3) Explore the design methods to resist progressive collapse of pyramid spacetruss structure.According to the characteristics of large number members of pyramid space trussstructure, this paper combined the response rate of bars with the energy change rate ofstructure system to evaluat the importance of elements based on conceptual judgment,and verified the method was applicable.Failure introduce equipments were designed on the important elements ofexperimental model. The study involved experiments conducted on progressivecollapse of testing model based on important element failure and mimiced thedynamic collapse process by ANSYS/LS-DYNA. The results revealed progressivecollapse mechanism of pyramid space truss structure and proved the validity of thefinite element analysis.Based on ANSYS/LS-DYNA, the paper analyzed failure characteristics and stress redistribution and load-bearing capacity of resisting progressive collapse whensingle or more important components failure, and revealed the progressive collapsemechanism of pyramid space truss structure. Finally, according to the analysis results,the design methods of pyramid space truss structure to resist progressive collapsebased on compression stability was proposed.