Study On The Seismic Secondary Fires Disaster In The Urban

China is a country of many earthquakes and the one of nation deeply suffering the most serious earthquake disaster in the world. The seismic disaster seriously threatens the people's life and property safety, also becomes an important factor to hinder the development of the harmonious social. The seismic secondary fire disaster is the most frequent seismic secondary disaster heightened seismic disaster damage. Moreover, the urbanization progress increasingly accelerates in our country. The study on the seismic secondary fire disaster seems more urgent.In recent years, the studies on the seismic secondary fire disaster were developed in the world. But it still lacks of systematic methodologies. Some relevant and critical science problems are still unresolved. In this paper, the systematic study on the seismic secondary fire disaster was carried out. Then, based on the studying results, the seismic secondary fire disaster simulation system was developed by using Visual C# and ArcEngine9.2 software package. The basic datum is from a small town in the South of China which had been finished the seismic disaster estimation work participated in by the author. The main work in this paper can be generalized as the following.1. Summing up the domestic and international achievement and progress in the research realm of the seismic secondary fire disaster and putting forward the research train of thought and target in this paperThe study on the seismic secondary fire disaster should include some fields. There are the hazard estimation of the single structure, the discrimination of the major secondary fire disaster hazard source, the hazard grade assessment of the urban housing estates and the calculation of the fire influence scope.2. Systematic discussing the relationship between the infrastructures and the seismic secondary fire disasterThe structures and other infrastructures are main the disaster-affected body. The damages of some infrastructures directly result in the secondary fire disaster. The damages of other infrastructures can weaken the fire fighting. Moreover, it may cause the more losses.3. Establishing the estimation model for the occurrence number of the seismic secondary fire disasterThe domestic and international seismic secondary fire (datum was collected. Then, the regression analysis was finished based on the datum. The estimation formula for the seismic secondary fire disaster was built with the parameters of the seismic intensity and PGA. It can provide basis for the prediction the times of the seismic secondary fire in the urban protection against and mitigation of earthquake disasters.4. Building up the probability model of the single structureThe influence factors of single structure seismic secondary fire were point out. Whether does combustible exist in the buildings or not, the combustibility of the combustible, the breakage of the combustible resulting from the earthquake damage and the probability of catching fire are the main factors. The probability model of the single structure seismic secondary fire was built according to these factors. The probability value of single factor was given under various circumstances.5. Building up the discrimination model of the major secondary fire disaster hazard sourceThe major secondary fire disaster hazard source is the general basis of the seismic secondary fire in the urban. The discrimination of major secondary fire disaster hazard source is the important mission in the urban protection against and mitigation of earthquake disasters. The model was built by using the Graham-Kinney method. In the model, the probability of the seismic secondary fire disaster, the frequent degree of exposing to the perilous source or the distance between the structure and perilous source are taken into account.6. Building up the hazard grade assessment model of the urban housing estates The hazard grade assessment model of the urban housing estates was built by using the AHP method. The influence factors to the urban housing estates secondary fire disaster include the earthquake damage of engineering structures in the area, the building density, the population density, the catching fire point density, the type of structures, the fire-fighting facilities condition, the fire-fighting station arrival time and the road density. The quantity standards of grading were determined. It can provide a workable evaluation method with urban secondary fire by using this model. It is also conductive to the urban daily fire safety.7. Building up the seismic secondary fire spread model between the buildings The seismic second fire spread model between the buildings was established at the engineering application standpoint on the basis of the actual circumstance of fire spread from the standpoint of engineering. In the progress, the fire spread parameters and critical distances were given according to the classes of structures. The influence factors of seismic buildings damage and wind velocity were taken into account in the model.8. Developing the seismic secondary fire disaster emulation systemThe VC# language and ArcEngine9.2 were applied to the development of emulation system by analyzing and investigating development soft. The frame of system adopts Net2.0 structure. In order to raise to the development efficiency, the third party control (Developer Express.NET v 7.2) was carried on the menu and interface design. The property,method and interface of objects in the ArcEngine object database were called by using VC#. The GIS parts of functions were carried out. The establishment of system is the very good attempt at applying GIS technique and computer technique to protection against and mitigation of earthquake disasters.