The Method Research Of Stability Evaluation About Rock-socketed Pile In Karst Areas And The Disposal Of Karst

With the development of the western region,more and more traffic engineering been constructed in the western mountainous areas.However,the Karst geological conditions are widely distributed in the western region.So the rock-socketed pile working on the Karst foundation inevitably.How to evaluate the stability of the bridge rock-socketed pile in Karst areas is the key to ensure the safety of engineering.The method of stability evaluation about rock-socketed pile in Karst areas and the disposal of Karst are discussed in this paper,The specific research work as follows:At first,the engineering characteristics of piles and Karst are summarized,as well as the present situation of research about the rock-socketed pile in Karst areas.Due to the complexity of load transfer about the rock-socketed pile in Karst areas,the calculation methods of the side resistance amount pile,soil,rock and the resistance at the tip of pile are investigated deeply.Also the stress mechanism and failure characteristics of the rock at the tip of pile are analyzed.It is set a foundation for the analysis of the rock-socketed in Karst areas.Secondly,the stability analysis method of rock-socketed pile in Karst areas are summarized based on the analysis of mechanical of load transfer.According to the practice,the model been gave in this paper.The ultimate bearing capacity of cave roof have punching failure are induced basis on the limit analysis upper bound and the work-energy principal,and the calculation formula of the safe thickness of cave roof are obtained.Then,considering the influence of the different boundary conditions to the punching failure model.The software of ABAQUS have been used to simulated different conditions.The model include clamped beam,clamped circular plate,clamped elliptic plate,clamped square plate,and the simulation results been analyzed.At last,the method of deal with the Karst in practice of engineering are discussed,as well as some reference value are provided for engineering practice.