Analysis On Monitoring Of Supporting Structure And Risk Countermeasures With Pit Of Zhengzhou Exhibition Hotel

Analysis on deformation of supporting structure and risk factors of supporting scheme with pit is very important, which not only has some significance to the secure construction with pit, but also to the improvement with techniques in the field of pit construction in our country. This paper derives from the project of pit in Zhengzhou Exhibition Hotel, a building that will be 280 meters high after the completion of the construction, as the highest building in Henan province. The pit in this structure is also a particular one in the mid area of China, which has characteristics of large scale, deep excavation, in a complicated construction environment. So, it is necessary to analyze the deformation of the supporting structure in this pit.According to the practical project, on the foundation of consulting with many references, research on the following issues will be done after the reservation of the knowledge.There are two optional supporting schemes in the early design stage, the scheme of pile-anchor supporting structure, and the scheme of pile-brace supporting structure. Comparison with these two schemes is performed from three angles of schedule, cost and deformation computation. The best scheme will be obtained to confirm with the scheme which is adopted after the experts'discussion on this pit. The risk factors in the chosen scheme will also be analyzed.Risk factors of the pit environment consist both uncertain element brought forward by the environment and the uncertain element belong to the supporting scheme itself. Numerical simulation software FLAC3D of geotechnical engineering is used to simulate the environment risk existing in pit construction. Settlement of the earth's surface and horizontal displacement of the supporting piles are simulated, results of the simulation are analyzed.Analysis on the supporting scheme is performed in three angles, including axial force in brace, horizontal displacement of the supporting piles and the horizontal displacement of the supporting structure, with the data from pit monitoring. The regular pattern as well as the tendency revealed by data is founded, contrasted with the results of the numerical simulation by FLAC3D, discussion on some problems in the comparison is carried out. Countermeasures against risk factors existing in pit deformation, precipitation design and deformation of supporting structure are brought forward. As the real damage appears in the practical project, dispose measures are also have been proposed.Research on risk factors in pit supporting scheme is performed systematically in this paper, it is analyzed the effect deriving from risk factors in pit project in two angles of numerical simulation and spot monitoring, which provides some reference to the promotion of construction techniques and risk management in pit project of our country.