According to in-situ self-balancing static loading test of uplift pile in moderately weathered rock, a FLAC3D numerical analysis model of rock-socketed uplift pile is established based on reasonable rock mechanics parameters and test data together with the geological condition of the project. By using this model, three uplift piles undergone self-balancing test until failure were simulated to determine the ultimate bearing capacity of each pile and to further examine the influence of rock socket depth on the ultimate bearing capacity of uplift pile and the variations of lateral resistance and axial force of pile with external load. Results demonstrate that: (1) The shear modulus and volumetric modulus of rock should be reduced by 1/10 of test values when building a rational numerical model. (2) The ultimate bearing capacity of rock-socketed uplift pile is mainly affected by the socketed depth of rock. Under the same condition, the ultimate bearing capacity of rock-socketed uplift pile increases with the socketed depth of rock and the length of pile, and the rock-socketed depth of pile should not be too small. (3) With the increase of rock-socketed depth, the side resistance of pile increases first and then decreases, and the middle resistance of pile contributes the most remarkably to the ultimate bearing capacity. (4) The diameter of uplift pile has size effect on ultimate bearing capacity.
Key words
rock-socketed piles /
self-balancing test /
load-bearing characteristics /
ultimate bearing capacity /
rock-socketed depth /
FLAC3D numerical simulation analysis
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1] 王耀辉, 谭国焕, 李启光. 模型嵌岩桩试验及数值分析[J].岩石力学与工程学报, 2007, 26(8):1691-1697.
[2] 何思明.抗拔桩破坏特性及承载力研究[J] .岩土力学,2001,22(3):307-319.
[3] 唐孟雄,陈 达.基岩内抗拔桩极限承载力的计算方法[J] .岩土力学,2015,36(2):634-638.
[4] 汪光满,宋仁乾,胡达敏,等.复杂岩溶地质条件下嵌岩冲孔灌注桩设计[J] .建筑结构学报,2015,45(增刊):85-87.
[5] JOHNSON S M, KAVANAGH C T. The Design of Foundations for Buildings[M].New York: McGraw-Hill Book Company, 1968.
[6] MEYERHOF G G. Uplift Resistance of Inclined Anchors and Piles[C] ∥Proceedings of the 8th International Conference on Soil Mechanics and Foundation Engineerin. Moscow: Kluwer Academic Publishers-Plenum Publishers, August 6-11, 1973: 167-172.
[7] DAS B M. A Procedure for Estimation of Uplift Capacity of Rough Piles[J].Soils and Foundations, 1983, 23(3):122-126.
[8] DAS B M. Principles of Foundation Engineering[M].Edition 7. Stanford, USA: Cengage Learning, 2010.
[9] CHATTOPADHYAY B C, PISE P J. Uplift Capacity of Piles in Sand[J].Journal of Geotechnical Engineering,1986, 112(9): 88-90.
[10] SHANKER K,BASUDHAR P K,PATRA N R.Uplift Capacity of Single Piles:Predictions and Performance[J].Geotechnical and Geological Engineering,2007,25(2):151-161.
[11] DESHMUKH V B, DEWAIKAR D M, CHOUDHURY D. Computations of Uplift Capacity of Pile Anchors in Cohesionless Soil[J].Acta Geotechnica, 2010, 5(2): 87-94.
[12] JT/T 738—2009, 基桩自平衡法静载试验技术规程[S].南京: 江苏科学技术出版社, 2009.
[13] JGJ 106—2014, 建筑基桩检测技术规范[M].北京:中国建筑工业出版社, 2014.
[14] GB 50007—2011,建筑地基基础设计规范[M].北京:中国建筑工业出版社, 2012.
[15] 刘 衡, 杨 波, 王铁行. 厚层沉渣嵌岩桩承载性能试验分析与数值模拟[J].铁道建筑, 2012,(12):93-95.
[16] 孙书伟, 林 杭, 任连伟. FLAC3D在岩土工程中的应用[M].北京:中国水利水电出版社, 2011.
[17] 桩基工程手册编写委员会. 桩基工程手册[M].北京: 中国建筑工业出版社, 1995.
PDF(2387 KB)
