岩土力学2018，Vol.39Issue(5)：1747-1752,1760,7.DOI:10.16285/j.rsm.2016.2371
膨胀土应力松弛的分数阶模型
Stress relaxation model of expansive soils based on fractional calculus
摘要
Abstract
To accurately describe the mechanical behavior of stress relaxation of expansive soils,the software element is constructed by applying the theory of fractional calculus to replace the ideal viscous element in the traditional element model.The damage degradation of viscosity coefficient is considered.A new three-element model is established to better reflect the nonlinear stress relaxation behaviors of Nanning expansive soils.The stress relaxation of Nanning expansive soil under different water contents is studied by a series of indoor tests.The relevant model parameters and stress relaxation equations are determined according to the analysis of the tested results.By comparing the proposed model with the traditional integer order models (such as the traditional St.Venant model and Nishihara model),the results show that the proposed model can more effectively simulate the whole process of the stress relaxation of the expansive soils.Furthermore,the proposed model has advantages on simple structure,few calculation parameters,high accuracy,easy to practical application.The research results provide a theoretical basis for the analysis of the stress relaxation of expansive soils under long term load.关键词
膨胀土/应力松弛/分数阶微积分/损伤劣化/松弛模型Key words
expansive soils/stress relaxation/fractional calculus/damage degradation/relaxation model分类
建筑与水利引用本文复制引用
张春晓,肖宏彬,包嘉邈,尹亚虎,尹铎霖..膨胀土应力松弛的分数阶模型[J].岩土力学,2018,39(5):1747-1752,1760,7.基金项目
国家自然科学基金(No.31270671,No.50978097).This work was supported by the National Natural Science Foundation of China (31270671,50978097). （No.31270671,No.50978097）
