真空预压固结解析解 - 河海期刊.DOCVIP

考虑真空度衰减及涂抹区渗透系数变化的 真空预压固结解析解 吴跃东1,2，吴鸿昇1,2，罗如平1,2，曾垂昌1,2 河海大学 岩土力学与堤坝工程教育部重点实验室,南京 210098；2. 河海大学 岩土工程科学研究所,南京 210098) 摘要：为更好将理论计算应用于实际真空预压工程并指导工程实践，假设真空度线性衰减，在此基础上建立了真空预压软基径向固结方程,得出超孔压的计算公式及固结度。研究了涂抹区渗透系数对固结的影响，分别给出了渗透系数不变和渗透系数线性变化时地基中平均孔压和固结度的解析解，并进行了分析。分析结果表明，真空度衰减系数k1、k2越小、井阻比n越小、涂抹区半径与排水体半径的比值s越小、非扰动区与涂抹区渗透系数比，真空预压效果越好。通过对嘉兴港真空预压的现场观测，发现本文的解析解与Hansbo解相比与现场实测数据更加吻合，并且考虑涂抹区渗透系数线性变化的解更符合工程实际。 关键词：真空度；线性衰减；涂抹区;超孔隙水压力；固结度 中图分类号：TU447 Analytical solutions for consolidation under vacuum preloading considering the degree of vacuum decay and smear zone permeability coefficient change WU Yue-dong1,2, Wu Hong-sheng1,2,Luo Ru-ping1,2,Zeng Chui-chang1,2 Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210098, China; 2. Geotechnical Research Institute, Hohai University, Nanjing 210098, China ) Abstract:An analytical consolidation theory of soft ground under vacuum preloading is established by assuming that the vacuum degree attenuates linearly in order to apply theoretical calculation to practical vacuum preloading projects and guide the project practice. Then an excess pore pressure and consolidation degree calculation formula are drawn. The analytical solutions for average excess pore pressure and degree of consolidation under the conditions of constant permeability and linearly changing permeability respectively are provided and verified. The analysis results show that the smaller k1、k2、n and s and the closer to s，the better vacuum preloading effect. Through the field observations of vacuum preloading in Jiaxing port, it is found that compared with the Hansbo’s solution, the analytical solutions provided in this note are more consistent with the measured data and the solution which considers linearly changing permeability in the smear zone is more consistent with engineering practice. Key words: vacuum degree; linear attenuation; smear zone；excess pore pressure; degree of consolidation 真空预压处理软土地基的方法得到了广泛的应用，真