考虑流变参数弱化综合影响的软岩蠕变损伤本构模型及其参数智能辨识  

Study on the creep damage constitutive model of soft rocks considering rheological softening and intelligent identification of the parameters

作　　者：高文华[1] 陈秋南[1] 黄自永[1] 刘栋[1] 

机构地区：[1]湖南科技大学岩土工程研究所,湖南湘潭411201

出　　处：《土木工程学报》2012年第2期104-110,共7页China Civil Engineering Journal

基　　金：国家自然科学基金(50874043);湖南省教育厅重点科研项目(09A028);湖南省科技计划项目(2010FJ3046)

摘　　要：根据损伤的定义和软岩的蠕变破坏特点,提出反映应力水平和时间因素对弹性模量弱化综合影响的软岩蠕变损伤变量的一般表达式,推导并建立软岩蠕变损伤演化方程,探讨损伤变量随应力水平和时间的变化规律。以Burgers模型为基础,建立可考虑参数综合弱化的软岩蠕变损伤本构方程。修正后的Burgers蠕变损伤本构模型体现了参数随时间增长和应力水平增大的弱化现象,反映了岩石材料的损伤劣化过程。基于粒子群优化算法(PSO)具有迭代过程简单、能有效地收敛到全局最优解等优良特性,提出基于PSO的蠕变损伤本构模型参数智能辨识的方法和步骤。采用MATLAB软件,编制基于粒子群优化算法的参数辨识程序。以某深部软岩试样蠕变试验为例进行验证分析,结果表明采用考虑参数综合弱化的蠕变损伤本构模型具有较好的实用性。According to the definition of damage and the characteristics expression of the creep damage variables is proposed to reflect the synthetic stress level and time. Based on these, the creep damage evolution of soft damage variables is discussed. Based on the Burgers model, creep of creep damage of soft rocks, a general influence on the elastic modulus softening by rocks is deduced, and the variation of the damage constitutive model considering the synthetic softening of parameters is established. The modified Burgers model can reflect softening phenomenon of parameters with the increases of time and stress level. Taking advantage of Particle Swarm Optimization （PSO）, the method and steps of using creep test of soft rocks.

关 键 词：软岩 蠕变 损伤变量 损伤演化 本构模型 粒子群优化算法 

分 类 号：TU45[建筑科学—岩土工程]