滨海高水位下渗透性风化岩的损伤模型研究  

Discussion on damage mechanics model of decomposed rock's permeability in high water level in coastal areas

作　　者：许德祥 黄明[1,2] 陈林靖[1] 沈启炜[3] 柴元四[3] 闫冬雪 

机构地区：[1]福州大学土木工程学院,福建福州350108 [2]重庆大学土木工程学院,重庆400045 [3]中铁十八局集团有限公司,天津300222

出　　处：《自然灾害学报》2017年第6期147-154,共8页Journal of Natural Disasters

基　　金：国家自然科学基金(41672290,41202195);福建省自然科学基金(2016J01189)~~

摘　　要：滨海地区风化岩层中高地下水位对地下工程的影响是长期被关注的热点问题。从岩土材料应力-渗流-损伤完全耦合作用下的弹塑性特点出发,提出一种适用于风化岩层的流固耦合弹塑性损伤本构模型。考虑岩土材料抗拉性能和抗压性能的差异,选取修正的Mohr-Coulomb破坏准则作为岩土介质的塑性理论模型,采用有效应力空间进行应力-应变计算,把塑性计算与损伤计算进行解耦,并对有效应力进行谱分解,分析了拉、压不同状态应力下岩土体材料损伤演化的不同规律,利用得到的应力、应变和损伤变量,与介质的渗流参数建立相应的关系,实现了应力-渗流-损伤的完全耦合。此外,基于Abaqus软件平台及回映算法编制了相应的非线性程序,结合算例将所得计算结果进行了系统分析,初步验证了该理论的可靠与合理性。研究成果可为滨海城市中深基坑开挖诱发地层渗透破坏等灾害的控制提供理论依据。The influence of high underground water on the underground engineering has been concerned over a long time in the coastal region covered by weathered rock. Considering the elastoplastic geotechnical material coupled with the stress and seepage, an elastoplastic damage constitutive model coupling fluid-solid is presented, which is suitable for weathered rocks. The modified Mohr-Coulomb criterion is suggested to consider the differences between tensile and compressive properties of the geotechnical material. The effective stress space concept is employed to determine the stress-strain curve by decoupling the damage calculation and plastic calculation. The damage evolution of geotechnical material is analyzed by decomposing the stress tensor into tensile and compressive stress states. And the different damage evolution of geotechnical material is reflected in different stress states. The relationship of mechanical parameters and permeability is obtained by combinating the factors of stress, strain and damage. Based on the abaqus and the return mapping algorithm, the theory referenced in this paper is applied to an example through developing a nonlinear finite element analysis program, which verifies the reliability and reasonableness of this theory. Results can provide theoretical basis for the control of ground seepage collapse in deep foundation pit excavation in the coastal region.

关 键 词：损伤模型 流固耦合 破坏准则 有效应力 风化岩 

分 类 号：TU4[建筑科学—土工工程] P315.93[天文地球—地震学]