Research On Disaster Prevention And Mitigation Of High-rise Building Under Construction Based On The Construction Progress

With the development of China’s urbanization and the urban renewal, high-rise buildingsare constructed like spring shoots and make the construction industry develop vigorously. Atthe same time, the accidents and disasters in the constructing process have caused greatdamage to people’s life and property and severely obstruct the sound and sustainabledevelopment of the construction industry in China. However, the study of disaster preventionand mitigation does not attract enough attention in the society. The current existing results cannot meet the objective needs what is necessary during the development of economics andsociety. Focusing on the study of disaster prevention and mitigation is quite meaningful forthe theoretical system complement of disaster prevention and mitigation project. It is alsoessential to largely decrease death number during the process of constructing, to reduce andavoid the delay of constructing and invest loss, and to enhance the sound, harmonious, andsustainable development of construction industry in China.According to the realities of projects and the present situation of theories, the authorstarts with the theoretical and practice significance of the disaster prevention and mitigation ofhigh-rise building, and constructs a three-dimensional structure of the study. Meanwhile, theauthor takes the disaster prevention and mitigation of the construction stages of high-risebuilding as the main line of this study, and put forward the countermeasures of the disasterprevention and mitigation of high-rise building. Concrete studies are conducted as follows:1) The concept of the building disasters of the high-rise buildings has been established,which has the natural and social characters; the building disasters of the high-rise buildingshave been indentified and classified into different varieties.2) Supporting structures of foundation pit have been summarized into a system andseveral failure modes of foundation pit projects have been concluded and analyzed; disastersof foundation pit projects have been induced and the causes for them have been analyzed fromthe subjective and objective aspects; the sources of the flood disasters threatening the safetyof the foundation pit have been concluded and the composition of the pore water pressure hasbeen analyzed; the differences between the two methods of calculation of water and earth pressure have been deeply studied; the method of calculation of water and earth pressureunder seepage has been provided and the conclusion that seepage is detrimental to thesupporting structure is reached; the effects of the seepage on the stability of the soil nailingsupporting structure at the clay area have been investigated and the calculation formula for theoverall stability coefficient has been given; based on the improved Fellenius method of slicesand the pseudo-static method, the effects of the earthquake on the complex soil nailingsupporting structure have been studied; the effects of the ground overload, overexcavation,late support, soil freezing and thawing and the changed of the around environmenton the foundation pit projects have been analyzed.3) The systematic concept of the scaffold of the high-rise buildings has been established;the types and causes of the scaffold accidents have been concluded and analyzed; the rules onthe calculation of the wind load of the scaffold in related codes have been discussed andsuggestions for improvement have been proposed, for instance, the calculation formula for thecomplex windshield coefficient φ has been given; the effects of the wind load on the scaffoldhave been studied from the aspects of frame and tie member; the model ofmulti-degree-of-freedom elastic system of the scaffold structure has been established and theconclusion that the horizontal earthquake action increases the possibility of the instability ofthe scaffold structure has been reached based on the bottom shear way; the elements thataffect the stability of the formwork system under the earthquake are listed; the effects of flood,fire and snow disasters on the scaffold have been discussed; the effects of the time-variationof the structural resistance of the concrete structure on the scaffold structure have beenanalyzed; different prescriptions of the maximum load of the formwork system in relatedcodes have been comparatively studied and reasonable suggestions have been proposed;The questions of the time-efficiency and road-efficiency of the force of the bracing system ofthe formworks have been proposed; the effects of different casting paths of concrete on theinternal force of the formwork supporting system have been concluded and analyzed.4) The effects of the earthquake on the crane towers have been researched from theaspects of the instable failures of the tower body, the breach of the crane jib and the decreaseof bearing capacity of foundation and the calculation method of the horizontal earthquake force has been given; the analyst shows that the existing structures have higher sensibility tothe earthquake than the projects under construction.5) The concepts of the disaster prevention and mitigation and countermeasures of thehigh-rise buildings under construction have been established; the basic theories of the disasterprevention and mitigation of the high-rise buildings under construction have been provided;the systematic and complex characters of the disaster prevention and mitigation of thehigh-rise buildings under construction have been proposed and analyzed; the level-system ofthe disaster prevention and mitigation of the high-rise buildings under construction have beenformed and the subjects, objects and the affiliated relations of different levels have beenanalyzed; the countermeasures for the disaster prevention and mitigation of the high-risebuildings under construction have been concluded from three research aspects, namely,technical and engineering aspect, administrative and organizational aspect, and social andstrategic aspect.The purpose of this study is to show the influence mechanism of all the disaster causingelement through doing a research on the high-rise building under construction, and to providethoughts and reference for the stereo metric formula precaution from the aspects of projectsand techniques, management and organization, society and policy and so on. At last the authorforecasts farther studies through the enlargement of research objects and the complement ofstudy methods and so on.