桩周后注浆技术是提高桩基承载力的重要措施。结合某工程勘察获得的场地土层物理参数,基于随机分形方法,运用Diamond-Square算法构建随机非均质地层模型;考虑桩基周围注浆过程中土层孔隙率、渗透率以及其他参数的动态变化过程,结合流体运动方程进行数值模拟。分析注浆过程中桩基周围土层物理参数的实时动态变化,获得浆液扩散及结石体的不规则分布情况;注浆后桩侧和桩端周围土体、结石体力学特性显著改善,桩周注浆加固效果明显。基于非均质地层模型开展注浆数值模拟计算,可以指导和评价桩周注浆加固过程。
Abstract
Post-grouting technique is an important means of improving the bearing capacity of pile foundation. According to the field physical parameters of soil layers at a project, an inhomogeneous formation model is constructed via Diamond-Square algorithm based on the random fractal theory. In consideration of changes in soil porosity, permeability and other parameters during grouting around pile foundation, the grouting process is simulated in association with the equation of fluid motion. Through analyzing the real-time dynamic changes of physical parameters of soil layers, the irregular distribution of slurry dispersion and stone body are obtained. The mechanical properties of soil and stone around the pile has improved significantly after grouting, indicating an obvious reinforcement effect. Numerical simulation of grouting based on inhomogeneous formation model could be used to guiding and evaluating the reinforcement process of pile grouting.
关键词
桩基 /
注浆 /
随机分形理论 /
非均质地层 /
加固效果
Key words
pile foundation /
grouting /
random fractal theory /
inhomogeneous formation /
reinforcement
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参考文献
[1] 张忠苗, 吴世明, 包 风. 钻孔灌注桩桩底后注浆机理与应用研究[J]. 岩土工程学报,1999,21(6):681-686.
[2] HUANG J, LYAMIN A V, GRIFFITHS D V, et al. Quantitative Risk Assessment of Landslide by Limit Analysis and Random Fields[J]. Computers and Geotechnics, 2013, 53: 60-67.
[3] 张继周, 缪林昌, 陈俊波. 苏中腹地湖相软土土性参数变异性统计描述[J]. 岩土力学, 2010, 31(2): 471-477.
[4] 蒋水华,杨建华,姚 池,等. 考虑土体参数空间变异性边坡失稳风险定量评估[J]. 工程力学, 2018, 35(1): 136-147.
[5] FALCONER K. Fractal Geometry: Mathematical Foundations and Applications [M]. Chichester: Wiley, 2003.
[6] 肖高逾, 周源华. 基于分形插值的地貌生成技术[J]. 上海交通大学学报, 2000, 34(5): 705-707.
[7] 宫英振, 牛海霞, 董正茂, 等. 分形多孔介质孔道网络模型的构建[J]. 农业机械学报, 2009, 40(11): 109-114,108.
[8] BARTOLI F, PHILIPPY R, DOIRISSE M,et al. Structure and Self-similarity in Silty and Sandy Soils: The Fractal Approach[J]. Journal of Soil Science, 1991, 42(2): 167-185.
[9] 陈建飞. 非均匀地层物性参数随机模型及其应用研究[D]. 宜昌:三峡大学, 2014.
[10]秦鹏飞, 符 平, 王 春, 等. 砂砾石土灌浆浆液扩散半径试验研究[J]. 长江科学院院报,2014,31(5):84-86, 101.
[11]雷进生, 刘 非, 王乾峰, 等. 非均质土层的注浆扩散特性与加固力学行为研究[J]. 岩土工程学报, 2015, 37(12): 2245-2253.
[12]雷进生, 刘 非, 彭 刚, 等. 考虑参数动态变化和相互关联的浆液扩散范围研究[J]. 长江科学院院报, 2016, 33(2): 57-61.
[13]燕 乔, 徐 枫, 莫世远, 等. 变态混凝土成孔注浆浆液扩散研究[J]. 长江科学院院报, 2016, 33(2): 91-93, 99.
[14]冉启全, 李士伦. 流固耦合油藏数值模拟中物性参数动态模型研究[J]. 石油勘探与开发, 1997, 24(3): 61-65.
[15]CHENG P, LI L, TANG J,et al. Application of Time-varying Viscous Grout in Gravel-foundation Anti-seepage Treatment[J]. Journal of Hydrodynamics, 2011, 23(3): 391-397.
[16]吴 稳, 周云轩, 李 行, 等. 分形布朗运动在水下地形模拟中的应用[J]. 计算机工程与应用, 2010, 46(25): 242-245.
基金
国家自然科学基金项目(51709155,51279092);湖北省自然科学基金项目(2013CFB218);三峡大学人才科研启动基金项目(KJ2014B004)
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