Study On Engineering Measures Of Pit Security Precipitation

At present,High- rise buildings, which was followed by deep foundation pit are both increasing. Because of its difficulty Jong construction period, and the high cost, deep excavation and shoring work project has been concerned .Specially as a result of the ground water influence, pit dewatering becomes the auxiliary project must be implemented in the deep-pit excavation process . However, the misconduction of foundation pit is bound to cause excessive groundwater, lowering produce surface settlement, and endanger the safety of surrounding buildings and facilities. Specially along with current urban improvement project increasing, the construction pit is located the place of the prosperous downtown area ,the main transportation line, underground pipeline intensive, and closing to the high-rise buildings, not only narrow construction site, pit and the outlying lower volume of the underground water level has harsh restrictions. This requests security precipitations must be implemented in foundation pit projects. Therefore, taking the security precipitations as the goal, the research of security precipitation project measure problem, has the practical significance in projects.First, this paper elaborates the present situation of research of the foundation pit security precipitation measure aspects on the present domestic and foreign actual projects in detail, and analyzes the exist problem. At the same time, on the basis of the basic theory of single well precipitation, simply introduces the problem of the ground water processing method at present. After that, in the simple, easy principle, the paper proposes a kind of new security precipitation measure - partial impermeable walls of a well measure. Finally through the experimental study, further confirmed the new security precipitation measure which the present paper proposed to improve the external groundwater table of foundation pit,protect the approaching building facilities safety remarkable effect, and produces the impermeable wall of a well parameter (impermeable wall corresponding to the central angleα) and the external axis r from the Department groundwater wells Z(r) counterparts relations Z(r)～α, might supply the actual center the security precipitation project reference to select.This paper presents a new type of security measures precipitation -- partial impermeable walls of a well measure, simple, convenient, easy to use in practical...