Up-down Construction Method Of Steel-pipe Column And Earthwork Excavation Research And Application

With the development of modern city, more and more importance is attached to the underground space. In the construction of many new buildings, we have to develop underground space after using up every inch of land available, thus calling for a higher standard for building design and building construction, and making it our only choice to adopt and optimize the construction process of basement. Since ordinary support types cannot meet the demands arising from the new building engineering without affecting the surrounding buildings, inner support and reverse construction method have come into being, which becomes more important now that we think highly of economic efficiency, social efficiency and environmental efficiency. Using reverse construction method, we can raise the safety level of underground engineering, decrease project cost, shorten the construction period of a project, and prevent the surrounding foundations from sinking. In the present study, we will give a detailed discussion about the reverse construction method, with regard to its concept, its theory, its categorization, and its development. In addition, we will explore the construction process and technical essentials of the reverse construction method, using as example the construction of Dongyue Residential Building(Guangzhou) and Beijingdong Buisiness Square(Guangzhou). The main content is as follows:We will sum up the construction process, construction method and management experience when putting into practice the reverse construction method, especially in Guangzhou district. We will introduce the application of micro steel pipe in the process of using reverse construction method. Due to the particularity of reverse construction method, we have to use steel pipes as vertical components. We will discuss how to position and fix the micro steel pipes when putting into practice the reverse construction method.We will discuss how to integrate the punching pile foundation and steel-concrete column. We effectively accomplished the task of positioning, monitoring and rectifying a deviation of steel columns under the wet foundation hole condition, thus realizing the continuous construction of vertical components when using reverse construction method.We will sum up the soil construction process, the key measures, management and organization experience while using reverse construction method. Since underground excavation is necessary when applying the reverse construction method, we must make careful plan as for reserving an exit for horizontal transportation of earthwork, vertical transportation of earthwork, lighting, and ventilation, so that the underground excavation can be conducted safely and smoothly.This is a case study of Dongyue Residential Building(Guangzhou) and Beijingdong Buisiness Square(Guangzhou). We systematically explore the problems and solutions for them in the construction preparation, construction process, construction technology, and construction organization, and, in particular, we put forward some reasonable suggestions and solutions in applying reverse construction method.