Evacuation Countermeasure Study For Emergencies In Location Of Dense Urban Mass

With the rapid urban expand and fast growth in population, number and area of dense urban mass location increased constantly with bigger city and higher level modernization for working in the smooth progress of different activity. Because of variety of the Location and the crowd, the kind of emergencies is more complex, and the frequency of accident is high. In case of same disasters happened, high economy load cause higher loosing in dense urban than other regions. Now, lack of emergencies management scheme in most of city make greater damage than before. Increasingly extruding Problem of urban integrative decreasing disaster has been listed in schedule. It is important for each city to constitute prevention measure and emergencies management scheme. According to more happened emergencies, personnel evacuation is absolutely necessarily to resolve emergencies. So it is the most important factor to decrease loosing that how to constitute a scientific, logical and feasible evacuation countermeasure.According to the characteristics of dense urban mass and evacuation, this paper provides three main safety hidden troubles factors, including human flow speed, location capacity and city traffic. The dialectic relation between the three factors and emergencies, and the relation of three factors are analyzed in the paper. After the data of human flow and speed are collected and analyzed in different conditions in location of dense urban mass, the values of running for lives speed and evacuation time are calculated. The calculation and reference ways of safety capacity and limit capacity are found based on the values of speed. The paper introduces the modern city traffic and analyzes that city traffic leads evacuation and supports works of succor.The paper analyze the current status of North Square of Xi'an Big Wild Goose Pagoda using spatial analyze function and networks analyze function, and it is get that design for position and number of exports accord safety standard , and circumjacent serving devices are self-contained so that it can satisfy the request of evacuation and succor. The preventive measures of emergencies are brought forward from urban planning, city design, constituting polity rules and professional technology management.