Frozen Soil Research On The Effects Of The Result Of Pile Static Loading Test In Dalian Area

In China, permafrost and seasonal frozen soil area accounts for more than 70% of total land area, due to the special nature of permafrost and sensitivity to the external environment, resulting in an impact on the basis of geotechnical structures or various buildings. Therefore, infrastructure investment is increasing every year.In frozen soil regions on the basis of various forms, the pile foundation as a deep foundation, with its adaptable in variety of geological and environmental conditions, being the ideal form in the basis of all types of buildings. So high demands is putting up with the vertical compressive bearing capacity and the vertical compressive static load test capacity. Currently, static load test of its test results with high reliability advantages can not be completely replaced by other detection methods. But now more and more projects, more duration in time, static load test was requested in the winter. In Dalian, static load test results is suspected wrong in winter, so retested after the thawing permafrost next year and found its bearer force does not meet the requirements, through the analysis, and found that the permafrost underground. It is due to impact on the bearing capacity of permafrost. At low temperatures, the soil freezes, freezing soil strength is greatly improved, to farther improve the bearing capacity of the pile; When the temperature rises, melting frozen soil, pile bearing capacity decline. Therefore, the results of static load test of the winter permafrost zone will yield inaccurate, it is necessary to pile foundation static load test permafrost areas of research and analysis.In this paper, a review of relevant literature and specifications and other information. First, a brief introduction to the basic conditions of permafrost and compressive bearing capacity of single pile testing, and the current research in the construction process and the problems do brief elaboration. Secondly, the mechanism of permafrost affect end bearing piles and piles of friction bearing capacity, calculate its theoretical capacity and settlement worth the results and analysis, and finally using three-dimensional fast Lagrangian differential software FLAC3D single pile program under the same conditions of the respective reasonable modeling, numerical simulation and theoretical results were compared analytical solution, proposed restrictions of static load test in the winter.