The Numerical Simulation And Analysis On Wind-load Of Large-span Structures

This dissertation is a part of the research project named "The research of wind load and wind-induced response on large-span structures" which is supported by National Engineering Research Center of steel. In the latest 30 years, large-span space structure is the form which is fastest growing. This form of structure usually has a large space with no internal columns and is relatively low. Because the roof is usually use of lightweight but high strength materials, compared to the main structure, it is more sensitive to wind damage and wind loads has become a major control load to this type of structure. These kind of structures' bodily form are complicated, there are no similar shape can be reference in the existing building structure load code, so the design of structure wind resistance lacks enough guidance. So the research to wind load characteristics of large-span roof structures have significance.At the present time, field measurement, wind tunnel' trial and numerical simulation are the three major research methods of the Wind Engineering. The core of the numerical simulation method theory is Computational Fluid Dynamics (CFD).With the development of physical turbulence model, coupled with the rapid progress of the computing technology, the simulation of the average wind pressure on the rigid wall buildings and the flow field around the structure has become a reality. On the wind engineering problems, based on general CFD software, the establishment of appropriate numerical models can meet the requirements of the engineering practice.In this paper, a calculation and analysis will be done to the distribution of the pressure on the surface of large-span structure; using CFD calculation software CFX12.0. The research contains three portions.(1)Combined the characteristics of large-span roof structure, the proposals of numerical simulation are put forward from the respect of computational domain size, grid and boundary conditions, discrimination scheme, turbulence model etc. And the standard 6m cube model is simulated using the proposed method.(2)From the basic geometric characteristics, five typical (flat roof, cylindrical roof, spherical roof, saddle-shaped roof, cantilevered roof) forms of large-span roof are selected. The geometry of roof has a major impact on the wind pressure distribution. The influence of different geometric parameters to the distribution of the wind pressure is studied. (3) Using the numerical simulation methods proposed in this paper, combined with the law of wind pressure distribution on typical large-span roofs, Shandong Yantai Fitness Center is selected as the research object to analyze its wind pressure distribution. Then the CFD results are compared to the wind tunnel test data.Through the above research and analysis, this paper provide the reference for the wind resistance's study and design of Large-span Structures, it also help people to enact the Large-span Structures'wind-load code, then sums up the useful of numerical simulation method on wind-load's study. At last, this paper looks forward the further work.