Study On Application And Anti-Sesmic Performance Of Staggered Truss System

The staggered truss system is a prospective steel structure system with advantages of large lateral stiffness, lightweight, low cost and convenient layouts of architectures.The background and characteristics of the staggered truss system are introduced in the thesis and summary is made about recent developments of the staggered truss system in China and abroad.A student apartment is taken as a case study and comprehensive research is made for structural performances of the staggered truss system by setting up a 3-dimensional FE model. The structural performances of the staggered truss system under vertical load, lateral wind load and lateral earthquake load and the dynamic characterictic of the staggered truss system are studied by FEA. The behavior of all kinds of members in staggered truss system is summarized and the important role of the floor system in coordinating lateral displacements between adjacent frames and enlarging structural stiffness is emphasized.Transverse 2-dimensional FE model of the staggered truss system is set up by arranging adjacent frames parallelly and coupling lateral displacements of all nodes on the same floor. Rationality and accuracy of the simplified 2-dimensional model are verified through comparative research with the 3-dimensional analysis model considering vertical load, lateral wind load, transverse earthquake load and dynamical characteristic.Based on the above FEM analysis, simplified design methods of the staggered truss system are deduced for vertical load, lateral wind load and transverse earthquake load and fundamental period. The rationality and accuracy of the simplified design methods are verified.The antiseismic performance of the staggered truss system is evaluated using Pushover analysis method, which is widely used recent years. The rationality of the Pushover method is verified by comparing with elastic-plastic time histoty analysis and the staggered truss system is proved to be structural system with excellent antiseismic performance.