高频振动贯入灌注桩套管土塞效应的数值分析
doi: 10.3969/j.issn.0258-2724.2013.01.008
Soil Plugging Effect of Sleeves Driven by High Frequency Hammers
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摘要: 为探讨大直径灌注桩套管在高频振动贯入时管端土塞效应的形成机理,采用三维颗粒离散元法进行了数值仿真分析,研究了贯入过程中套管内、外土颗粒的位移、速率与接触应力、土塞高度、孔隙率和土体剪应力的变化.仿真结果表明:高频激振力越大,套管贯入深度越大,相应地管内土塞高度也越大,且超孔隙水压波动的最大幅度和幅值越大;土塞上部孔隙率较大,下部土体较密实.在高频振动贯入过程中,套管端沉入处的超孔隙水压幅值最大,同一时刻土塞内的超孔隙水压随深度增大;管内土颗粒在振动开始时以较小幅度上移;套管端部颗粒接触数目随贯入深度和振动频率的增大而增多,且接触应力和土体剪应力比其他区域大.Abstract: In order to investigate the formation mechanism of soil plugging effect when a large-diameter bored-pile sleeve is penetrated by high frequency hammers, numerical simulation analyses were performed by using the 3D granular discrete element method. Variations in the displacements, velocities, contact stresses of soil particles inside and outside the sleeve, the height of soil plug and as well the porosity and shear stresses in soil plug with sleeve driving were investigated numerically. The numerical results show that the larger the high-frequency exciting force is, the larger the driving depth of a sleeve and the height of soil plug inside the sleeve are. At the meantime, the maximum fluctuation range and fluctuation amplitude of pore water pressure are large with the increase of the exciting force. Porosity in soil plug is larger at its top than at its lower part. During the process of the sleeve driven by a high frequency hammer, the maximum amplitude of pore water pressure appears at sleeve end. The larger the penetration depth is, the larger the pore water pressure becomes. Displacements of soil particles in the sleeve are small at the beginning. The contact number of soil particles at sleeve end raises with the increases of driving depth and vibration frequency. Moreover, contact stresses and shear stresses at sleeve end are larger than those in other regions.
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PAIK K, SALGADO R, LEE J, et al. Behavior of open- and closed-ended piles driven into sands[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2003, 129(4): 296-306. MATSUMOTO T,TAKEI M. Effects of soil plug on behavior of driven pipe piles[J]. Japanese Society of Soil Mechanics and Foundation Engineering, 1991, 31(2): 14-34. RANDOLPH M F, MAY M, LEONG E C. Soil plug response in open-ended pipe piles[J]. Journal of Geotechnical Engineering, 1992, 118(5): 743-759. HENKE S, GRABE J. Numerical investigation of soil plugging inside open-ended piles with respect to the installation method[J]. Acta Geotechnica, 2008, 3(3): 215-223. LEONG E C, RANDOLPH M F. Finite element analyses of soil plug response[J]. International Journal for Numerical and Analytical Methods in Geomechanics, 1991, 15(2): 121-141. LIYANAPATHIRANA D S, DEEKS A J, RANDOLPH M F. Numerical analysis of soil plug behaviour inside open-ended piles during driving[J]. International Journal for Numerical and Analytical Methods in Geomechanics, 1998, 22(4): 302-322. 倪淯丹. 大直径灌注桩套管高频振动贯入机理分析. 福州:福州大学土木工程学院,2010. AKGUN H, DAEMEN J J K. Design implications of analytical and laboratory studies of permanent abandon-ment plugs[J]. Canadian Geotechnical Journal, 1999, 36(1): 21-38. MILLER G A, LUTENEGGER A J. Influence of pile plugging on skin friction in over consolidated clay[J]. Journal of Geotechnical and Geoenvironmental Engineering, 1997, 123(6): 525-533. MUHAMMAD S I. Discrete element method of cone penetration testing in coarse grain soils. Alberta: University of Alberta, 2004. TANAKA H, MOMOZU M, OIDA A. Simulation of soil deformation and resistance at bar penetration by the distinct element method[J]. Journal of Terrame-chanics, 2000, 37(1): 41-56. 桑原秀彦,麻生稔彦. Pile driving analysis using distinct element method. 山口:山口大学工学部,2003: 53-59. 曾远,周健. 砂土的细观参数对宏观特性的影响研究[J]. 地下空间与工程学报,2008,2(3): 499-503. ZENG Yuan, ZHOU Jian. Influence of micro parameters of sandy soil on its macro properties[J]. Chinese Journal of Underground Space and Engineering, 2008, 2(3): 499-503. KONIETZKY H, GUERIN F. Modelling of the Chagan underground nuclear test with the discrete element method[J]. International Journal of Blasting and Fragmentation, 1998, 3(2): 295-312. LOBO-GUERRERO S, VALLEJO L E. Influence of pile shape and pile interaction on the crushable behavior of granular materials around driven piles[J]. Granular Matter, 2007, 16(3): 241-250. DEEKS A J, RANDOLPH M F. Numerical analysis of soil plug behavior inside open-ended piles during driving[J]. International Journal for Numerical and Analytical Methods in Geomechanics, 1998, 22(4): 303-322. 周健,陈小亮,周凯敏,等. 静压开口管桩沉桩过程模型试验及数值模拟[J]. 岩石力学与工程学报,2010,29(2): 3840-3846. ZHOU Jian, CHEN Xiaoliang, ZHOU Kaimin, et al. Mddel test and numerical simulation of driving process of open-ended jacked pipe piles[J]. Chinese Journal of Rock Mechanics and Engineering, 2010, 29(2): 3840-3846. IGOE D, DOHERTY P, GAVIN K. The development and testing of an instrumented open-ended model pile[J]. ASTM Geotechnical Testing Journal, 2010, 33(1): 72-82.
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