Research On The Reliability Of Bearing Capacity Of Cast-in-Situ Pile In Xigeda Rock

The Xigeda-rock is widely distributed in Xichang-Panzhihua region in Sichuan Province. It belongs to extreme soft-rock with special characteristics, for example, it can be mashed and softened by water and will rupture when being dehydrated. The research datum about cast-in situ pile in this rock is badly scarce. The clear and complete computational methods in current criterions have not yet been found. Based mainly on the subject " Testing Study on Bearing Properties of Pile Foundation In Xigeda-Rock " under the western traffic scientific research project" Research on Highway Construction Techniques in Xiged-Rock ", carries on the fail-safe analysis to pile capacity . The topic group carries on the in-situ text to 13 grout piles in Xinjiu and Puba . The author rules about nine piles from the test result, and associated with "Road Arch of bridge Ground And Foundation Design Standard"(JTJ024-85) ("Road Ground Standard") The author applies for the formula of the bearing of friction grout pile in "Road Ground Standard" , and calculates the the axial bearing capacity about the text piles . Finially, the author contrast the materials between text pile and calculation and establishes the dimensionless limit state equation ; Then the author discusses the analysis method about Reliability. The author establishes the computation though M-C law's (Monte Carlo) by C , and finally does some judgment about bearing properties of pile foundation In Xigeda-Rock. The result indicates that the result is higher than the goal Indicators of Reliability [5].The bearing properties of pile foundation In Xigeda-Rock can solve by friction pile. The result is very reliable, and its indicators of reliabilityβis more precise than the standard in "construction reliability design standard" (GB50068-2001).