任意附加应力下竖井径竖向耦合固结等应变解  

Equal strain solutions of radial and vertical coupled consolidation by vertical drains under arbitrarily distributed ground soil stress increase

作　　者：雷国辉[1] 蒋春霞[1] 施建勇[1] 

机构地区：[1]河海大学岩土工程研究所,南京210098

出　　处：《岩土力学》2006年第2期173-178,共6页Rock and Soil Mechanics

摘　　要：竖向排水体包括砂井和塑料排水板已广泛应用于加速软黏土地基的固结。不同形式的轴对称条件下含竖向排水体均质各向同性地基的固结解析解答也相继被提出,而各种解答均假定地基中附加应力在竖向排水体的深度范围内是均匀分布的。显然,当竖向排水体深度与地面堆载区宽度的比值相对较高,或竖向排水体的影响区域靠近地面堆载区的边缘时,这个假定并不适用。为此,在现有径竖向耦合固结等应变解的基础上,提出任意分布的地基附加应力条件下的解答,并分析附加应力分布形式和线性加载速率对地基固结的影响。结果表明,均匀分布的附加应力条件下的解答低估了地基的固结速率,而瞬时加载条件下的解答则高估了地基的固结速率。Vertical drains including sand wells and prefabricated drains have been widely used to accelerate the consolidation of the ground consisting of soft clays. Various forms of analytical solutions have been proposed from time to time for evaluating the consolidation of homogeneous and isotropic ground with vertical drains under axisymmetrical conditions. In these solutions, however, the stress increases in the ground were assumed uniformly distributed along the depth of the vertical drain. It is evident that this assumption is not applicable to the cases where either the ratio of the depth of the vertical drain to the breadth of the surcharge-applied area is relatively high or the zone of influence of the vertical drain is in the vicinity of the edge of the surcharge-applied area. on the basis of an existing equal strain solution of radial and vertical coupled consolidation, this paper presents a solution for the situation that the stress increase in the ground is arbitrarily distributed along the depth of the vertical drain. In addition, the effects of the stress increase distribution and ramp loading rate on the ground consolidation are analysed. It has been found that the consolidation solution for a uniformly distributed stress increase underestimates the consolidation rate of the ground, whereas the solution for an instantaneously applied loading condition overestimates the consolidation rate.

关 键 词：固结 竖向排水体 等应变 附加应力 井阻 涂抹 瞬时加载 线性加载 

分 类 号：TU41[建筑科学—岩土工程] TB115[建筑科学—土工工程]