The Analysis System Of Wind Damage Loss On Urban Vulnerable Structures

Cyclone vulnerable structures are easily damaged by the strong wind in the city, such as glass curtain wall of the high-rise building, large outdoor billboards, ads/slogans on the wall, decorations of the building, the air conditioners out of the building, traffic system, the city greening trees and so on, these are the weak points of the city’s storm defense. Strong winds may cause street trees of the city branches broken or trunk lodging, large billboards damaged or collapsed and it will make economic loss even casualties. These wind vulnerable structures are the hazard of urban safety. So, this paper takes advantage of the wind field dada of the numerical simulation and the data of the automatic stations and put forward the analysis method of the city’s cyclone vulnerable structures to analyze the cyclone losses in the city based on the vulnerable models. Most current researchers for the cyclone studies of the city area only focus on the wind speed, neither think about the angel between the wind direction and the board of the vulnerable structures in the wind field area, nor the weight of the structures. In order to remedy the shortages, we add these two factors in the calculation of the models according to the advertising design standards. It will make the analysis more reasonable.This paper gets the calculation method which complies with the requirements of the mechanical calculation standard according to the wind load regulation; billboards design norms, steel structure design specification and building structure load regulation. Based on these standards, the paper simplified the model according to certain simplified principle and then chosen the suitable solution of the model. The analysis system brings about the wind field data of the numerical prediction and the records of the automatic station as the data resource. We use the mathematical model to analyze the vulnerable structures and get the formula of the solution. The paper took advantage of the Visual Studio2008platform and the efficient c++language to establish the analysis system and import the wind field data and cyclone vulnerable model to the system. The system can read and display many types of data and realize the basic operations of the map layer and the data using MFC (Microsoft Foundation Classes).Finally according to the intensity of the different structure, this paper sets a limit value to judge the level of the loss and realize wind field data’s visualization on the display window by GDI, window coordinates mapping technology and double buffering technology. This system can obtain the precise wind field data through the interpolation model. This model can solve the problem of the wind field data’s low resolution and get a accurate calculation of the vulnerable structures. Through the analysis module we can query the precise coordinate position, accurate wind field data and the loss level of the vulnerable structures.In urban wind simulation analysis module we can input parameters such as wind speed and direction to calculate the maximum stress and damage level of the five typical vulnerable objects.We can output the analysis results so as to compare with the historical data and other sources of data, even make the accurate forecast and warning for regional wind disaster.