Analysis On Wind-induced Damage Of The Long-span Roof Cladding Structure

The long-span roofs have been widely used in large public buildings because of its aesthetically great out looking and its high performance. This kind of structures are usually highly weighted and have small damping, thus Large-span roof systems are sensitive to wind action and may frequently be damaged under strong winds, especially when their shapes are relatively complicated. With the development of computational hardware technology and the theory of computational fluid dynamic, the computational stimulation techniques plays an important role in the wind engineering community by its unique merits.Using the SST k-ωturbulence model, the numerical simulation of wind-induced continuous damage of a 2D long-span roof structure is conducted by CFX11.0 to investigate the external and internal wind pressure coefficients near the opening hole. From this investigation, it can be obtained that several factors result in this damage, including the interaction of wind and roof system, wind-resistance details and design codes and so on. Based on this field survey, some suggestions on prevention or mitigation of wind-induced damage are given on for large-span roof system. The research work of this paper mainly focused on the following aspects:1. Various flat roof long-span structure with different destructive opening were numerically simulated, and calculation results of which were compared with inner pressure estimation theory. The reliability of data was confirmed by comparing numerical model from reference with this method on the results.2. The geometrical shape mutations at the edge of long-span flat roof was weak link, so wind-induced damage on roof often started at this spot. To study regulation for changes of wind stress factor caused by wind-induced continued damage at roof opening, the process of wind-induced damage on long-span flat roof was numerically simulated on two dimensions with various working condition, according to different inlet size and location.3. By the same method in 2, the process of wind-induced damage on long-span spherical roof was numerically simulated on two dimensions. Considering that this roof structure was obviously influenced by rise-span ratio, regulation for changes of wind stress factor caused by wind-induced continued damage at roof opening was studied at high and low rise-span ratio respectively, which can provide local wind force proofing design of long-span roof with some reference.4. Tapered vortex and columnar vortex area were dangerous spot for the flat roof, therefore, the changes of partial pressure after the flat roof broke was simulated at 3-d full scale and the regulation for changes was summarized. Compared the regulation of changes with wind tunnel test results in detail, feasibility and advantage of wind load CFD numerical simulated method were showed on calculation for wind pressure of long-span roof structure.66 figs,5 tabs,44 reference.