Aerodynamic Measures Of Low-rise Buildings In Wind-Resistance Design

In recent years, due to the aesthetic appearance, high rate of space utilization, economical usage of steel and rapid construction speed, light weight steel portal frame structure has been widely used in factory building of science and technology development zone and industrial zone. The kind of structure is relatively to have larger span and light weight and hence has no advantage in wind resistance. Along the coastal areas where typhoon appears frequently, portal steel frame structures were always severely damaged. The roofing structure is rent and blown; the steel frame structure is thrown off. Portal steel frame structure is the majority of building structure damaged by typhoon and became the victim of typhoon.Due to the severe loss caused by the typhoon, the engineers are now highly concentrate to find out various ways in wind resistant solution for the portal steel frame structure. Unfortunately, no good solution was found to solve the problem and then the portal steel frame structure still encounters severe damage caused by typhoon. Following are some of the reasons that caused the problem to occur: Portal steel frame structure is too light, large flexibility, small-damping, low vibration frequency and sensitive to wind load; high speed wind. Every year our country encounter 3 to 4 times of typhoon attack. Strength of the wind at the area around the center of typhoon is usually above level 12. The wind pressure value is exceeded the value provided from "Loading code for design of building structure." Too much concentrate is placed on the reinforcement of structure and connection strengthening to resist wind.In order to prevent wind disaster, the dissertation suggests using wind transportation method basing on use of aerodynamic theory in portal steel frame structure design. Wind load and load effect is reduced by changing appearance of structure or installing some ducting settings on the portal steel frame. With reference to DaYu flood-control experience, the new method replaces the concept of "wind resistant" as new concept of "wind transportation". It creates an advance in efficiency and economy in solving the wind problem.The dissertation has used the numerical simulation to analyze the effect of parapet wall on...