Work Mechanisms of Pile Foundation in the Karst Region

Abstract:

The stability and deformation characteristics of the pile foundation in the Karst region of the super big railway bridge Chaogou under different loading levels are analyzed using the FDM-software, FLAC^3D. In the analyses the socketed depth of piles, the properties of soil and rock mass, the scale, space position and filling situation of the Karst caves and the features of the contact interfaces between piles and soil and rock mass were taken into account. The research results show that the original design of the pile foundation is safe and the safety coefficient is greater than 2. The bond strength of the contact surface between pile and soil and rock is a controlling factor for the stability of pile foundation. Therefore, injection after construction is suggested to be used when needed, in order to increase the bond strength of the contact surface. The research leads to a conclusion that the mechanisms and the characteristics of the rock socketed piles can be more clearly interpreted in numerical analyses by referring the principle of the interaction between piles and rock, pile foundation and Karst, resistance of both pile ends and sides.

• Periodical: Applied Mechanics and Materials (Volumes 170-173)
• Pages: 88-92
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.170-173.88
• Online since: May 2012
• Authors: Gui Jun Wang*, Yong Zhang
• Keywords: Karst, Numerical Analysis, Pile Foundation, Rock Socketed Pile, Work Mechanisms

References

[1] Bai Risheng. Rules and Remedies of Surface Subsidence in Karst Area. Soil Engineering and Foundation, 2001, 15(4): 34-38 (in Chinese)

[2] Zhou Jian-pu, Li Xian-min. Methods of Stability Analysis in Karst Foundation. Mining and Metallurgical Engineering, 2003, 3(1): 4-7, 11 (in Chinese)

[3] Gong Kunfeng. Discussion on Surface Subsidence in Karst Region and its Treatment. Geotechnical Engineering World, 2004, 7(12): 56-58 (in Chinese)

[4] Hu Chang-shun, Bao Huiming. Neural Network Prediction of Karstic Ground Collapse. Journal of Engineering Geology, 2002, (3): 299-304 (in Chinese)

[5] Chen Xiao-ming. Cause Analysis and Quasi-quantitative Prediction on the Collapse of Karst Overburden. Chinese Journal of Rock Mechanics and Engineering, 2002, 21(2): 285-289 (in Chinese)

[6] Shi Pei-dong, Liang Jin-yu. Vertical Bearing Capacity of Rock-socketed Piles. Chinese Journal of Geotechnical Engineering, 1994, 16(4): 32-39 (in Chinese)

[7] Lü Fu-Qing, Wu Wen, Ji Xiao-hui. Research and Discussion On the Axial Static Load Testing Results of Rock-socketed Bored Pile. Rock and Soil Mechanics, 1996, 17(1): 84-96 (in Chinese)

[8] Dong Jin-rong, Lin Sheng-tian, Dai Yi-ming. The Load Tranfer Behavior of Large Diameter Cast-in-Situ Pile in Crushed Pebble Stratum. Chinese Journal of Geotechnical Engineering, 1994, 16(6): 123-131 (in Chinese)

[9] Liu Xing-yuan, Zheng Ying-ren. Analysis on the Parameters to Affect Behavior of Rock Socketed Segment of Piles. Chinese Journal of Rock Mechanics and Engineering, 2000, 19(3): 383-386 (in Chinese)

[10] Ming Ke-qian. Analysis of Bearing Mechanism of Socketed Pile. Rock and Soil Mechanics, 1998, 19(1): 65-69 (in Chinese)

[11] McVay M C, Williame R C. Design of socketed drilled shafts in limestone. Journal of Geotechnical Engineering, 1992, 118(10): 194-197

DOI: 10.1061/(asce)0733-9410(1992)118:10(1626)

[12] Vogan R W. Discussion on friction and end bearing tests on bed rock for high capacity socket design. Can. Geotech. J, 1997, (14): 156-158

DOI: 10.1139/t77-014