路堤软土地基超载卸载再加荷沉降预测分析  

SETTLEMENT PREDICTION OF SOFT SOIL EMBANKMENT UNDER OVERLOADINGUNLOADING AND RELOADING

作　　者：杨帆[1,2] 夏唐代[1,2] 周飞[1,2] 俞帆 YANG Fan;XIA Tangdai;ZHOU Fei;YU Fan(Research Center of Coastal and Urban Geotechnical Engi.,Zhejiang Univ.,Hangzhou 310058,China;MOE Key Laboratory of Soft Soils and Geoenvironmental Engi.,Zhejiang Univ.,Hangzhou 310058,China;Zhejiang Provincial Institute of Communications Planning,Design ＆ Research,Hangzhou 310006,China)

机构地区：[1]浙江大学滨海和城市岩土工程研究中心,杭州310058 [2]软弱土与环境土工教育部重点实验室(浙江大学),杭州310058 [3]浙江省交通规划设计研究院,杭州310006

出　　处：《低温建筑技术》2018年第10期72-76,85,共6页Low Temperature Architecture Technology

基　　金：浙江省交通运输厅科技项目(2015J10)

摘　　要：结合工程实例,验证了增量双曲线法在超载卸载再加荷作用的软土地基中预测最终沉降的可行性,并通过自编迭代程序,分析了不同沉降初始时刻t0对预测最终沉降的影响。同时,分析了路堤软土地基在超载卸载再加荷全过程中沉降随时间的变化规律,并研究了沉降速率与最终沉降量关系,提出了修正系数。研究结果表明,不同沉降初始时刻t0对预测超载卸载再加荷作用的软土地基最终沉降影响较大,建议沉降初始时刻t0选取第一级荷载恒载期中点;沉降速率随时间呈指数曲线递减;利用修正系数η可由沉降速率反算最终沉降量,修正系数η范围为0.05～0.08。A case history about soft soil embankment under overloading-unloading and reloading assesses the feasibility of incremental hyperbola method to predict the final settlement. At the same time, the influence of different initial time t0 on the final settlement was discussed. The law of settlement rate changing against time and the relationship between settlement rate and final settlement were analyzed. Besides, a new corrected coefficient was obtained. The results show that the final settlement is sensible to the initial time t0 which can reduce the complexity of data analysis and improve the accuracy of the prediction when t0 is the midpoint of the first constant load. The settlement rate decreases exponentially with time.Final settlement can be calculated by settlement rate and the corrected coefficientwhich is 0.05-0.08.

关 键 词：超载 软土地基 最终沉降 沉降速率 

分 类 号：TU433[建筑科学—岩土工程]