Design Theory Research On The Load Transferring Capacity And The Optimization Design For Rock-Socketed Pile Group In Guizhou Karst Area

Rock-socketed piles are the important foundation type for large building in mountain area. Although a lot of research was developed in the field of geotechnical engineering and foundation engineering, It's blank to the bearing mechanism and optimization design of rock-socketed pile group. This paper made a systematic exposition of mechanical properties for layered rock mass and bearing mechanism of rock-socketed pile. On the basis of this, the load transferring capacity and the optimization design for rock-socketed pile group is studied thorough, by 3D finite element numerical simulation. The obtained achievements are listed as follow:1. According to the concludes and summarizes of the existing research results to layered rock mass, mechanical properties for layered rock mass is researched systematically from the view of strength and deformation; the stress characteristics for foundation effect directly on the upper of rock is analyzed on leveled and declined layered intrusion situation.2. Focus on the bearing behavior of rock-socketed pile, bearing mechanism, influencing factors and calculation method for side resistance and end resistance in whole resistance rock-socketed pile is analyzed. On the basis of this, this paper discusses the bearing mechanism of rock-socketed pile group, and summarizes the deficiency of the design method for rock-socketed pile in existing standard.3. By using three-dimensional finite element procedure, the calculation model of rock-socketed pile group was established. Through P-S curve and stress state for rock-socketed pile group, the bearing load process of rock-socketed pile group is researched. The paper discusses effection factors of bearing behavior such as pile length, rock-socketed length, pile strength, bedrock strength.4. Based on the established calculation model and 3D finite element numerical simulation, the variation of bearing behavior for rock-socketed pile group is researched on changing the pile length and rock-socketed length. And principle of optimum design for rock-socketed pile group is summarized systematically.This article firstly roundly and systematically theoretical studies the load transferring capacity and optimization design of rock-socketed pile group in layered rock mass of Guizhou Karst region. The research has significant theoretical meaning, practical meaning for further investigating working mechanism of rock-socketed pile group. Especially the optimization model provides a wide application prospect for the actual engineering.