Structure Analysis And Scheme Comparison Of The Large-span Steel Roof Truss

This article submits the food factory site building on large span in the industrial zone as the project background. The project adopts the Mixed structure with Concrete Column and Light Steel Roof, which takes fully advantage of good compressive strength of concrete and steel of high strength performance. which is a 33 meters large span structure factory building. Therefore web plate thickness will increases to meet the reasonable ratios of height to thickness and steel usage will fold increase, which compared with vierendeel truss stiffened steel roof truss is not economic. In the structure of large span, steel beam will be generated large deflection, and the steel beam will generate horizontal thrust to concrete pillars. So the scheme will be improved, which lever plain girder structure and flat tube truss structure will be adopted. Under the premise of structural performance such as strength, stiffness, overall stability and local stability, three projects will make comprehensive evaluation about mechanical performance, steel demand and construction. Then select a reasonable method of model for conducting the structure finite element analysis and comparison to reduce the demand of steel and the investment of overall construction. The main work is as follows:1. The article adopts a engineering concrete column plain girder bent frame structure as a basis, and analyzes the influence of concrete column solid web steel beams bent frame structure, steel beam with solid-web, three kinds of planar truss structure influence on the engineering economy.2. According to the report of the engineering geological investigation and the structural design of standard procedures,and select the basic conditions of seismic grade, site type, load, wind load design. Then choose primary section.3. According to "load code for the design of building structures"GB50009-2012, choose the working condition with control function to apply on the steel beam, use software SAP2000 to establish three options model and then calculate.4. According to the finite element analysis of the model, the paper calculates the components of normal section strength, plane integral stability and plane integral epitaxial integral stability. Meanwhile, to ensure the deflection of beam and truss do not go over the permissible value, the paper designs the cross section in line with the bending moment diagram. Then compare the actual data and the finite element results to calculate the rationality of the results and optimize the scheme.5. To choose the most economical solution from three projects, study corresponding steel consumption, force analysis and so on.