Plus Story Building And The Large Span Roof Static Wind Load Numerical Simulation Studies

The structure with steel construction light-duty roofing system is quite different with other roofing system on anti-windy loading, this kind of structure is strongly affected by partial windy loading. Many investigation result about windstorm shows, the damage sample of large modern structure by windstorm is not common, but the windy storm damage sample of part-superficial spalling and part roofing tilting are commonly occur. Especially the windstorm and typhoon attack the whole roofing to broken, so we need pay more attention to the anti-windy system of steel construction light-duty roofing, and it also bring new subject to anti-windy design calculation.For when the wind flew through large-span roofing structure, it will create complex airflow breakaway and reattachment, the wind pressure distribution of large-span roofing structure is very sophisticated, and the alteration gradient of wind pressure are very large from leading to the end part, so a single physical coefficient reflect difficultly the wind loading of roofing. But the numerical simulation of CFD can accurately simulate every kind of wind pressure distribution of roofing system, and bring the important parameters that the anti-windy calculations of long-span roofing needed, and provide significant technical measures to the anti-windy design.In actual production and living, some structure built have not meet the challenge, for the land limited and so on, it cannot build new structure, some proprietor build another structure on the existing building. To decrease the disadvantage factor to the existing buildings, the best choice is steel construction light-duty roofing system. The added-layer is up the fifth and sixth floor, but the applicable codes and standards had not explanation to this kind of wind-loading, the design organization and the professional steel construction company calculated wind loading by increasing the calculation height from the existing structures. But it does not match the real conditions, and the wind loading calculation of the added layer construction have not be attention to. Above all, we made some work below:1. The wind pressure distribution and wind loading sampling by the numerical simulation of CFD to the added steel light-duty roofing system are approached. According to the result of numerical simulation, To calculate the wind loading of the added steel light-duty roofing system, the calculation of codes are reformationed, put forward the new formula. Every roofing is given a new wind pressure quotient.2. It take the the numerical simulation of CFD to simulate the practicability of long-span roofing wind loading by the example of membrane structure roofing of shang-hai pedestrian mall public square in zhengzhou.3. The main reason of roofing broken is dynamic effect of flow separation,the pressure inside and outside under the wind loading. for the model in our research is rigid body model, so the two former factor is analyzed deeply.4. Finally, the application of the numerical simulation of CFD are prospected.