摘要
研究循环荷载作用下饱和软黏土的累积变形对计算交通荷载引起的地基沉降具有重要意义。对饱和软黏土分别进行围压为100k Pa、150k Pa、200k Pa的等向固结动应力比为0.1、0.2和偏压固结动应力比为0.06、0.1、0.2的循环加载试验,得到轴向循环塑性应变与时间的关系,分析得到围压、动应力比及固结形式对轴向循环塑性应变的影响规律;将Abel黏壶引入开尔文模型,得到分数阶开尔文模型;利用遗传算法优化轴向循环塑性累积应变的开尔文模型和分数阶开尔文模型的参数,通过分析两组模型的计算值与试验值的对比曲线,得到分数阶开尔文模型更适合模拟计算循环荷载下饱和软黏土的累积变形。
To study the accumulative deformation of saturated soft clay under cyclic load has practical significance for foundation settlement calculation caused by the traffic load. The cyclic loading tests of the isotropic dynamic stress ratio of 0.2, 0.1 and the anisotropic consolidation dynamic stress ratio of 0.06, 0.1,0.2 are conducted for saturated soft clay, whose confining pressure is respectively 100kPa, 150kPa and 200kPa. The relationship of axial cyclic plastic strain with time as well as the influencing rule of confining pressure, dynamic stress and con- solidation form to axial cyclic plastic strain are gained. The Abel dashpot is introduced into the Kelvin model, and the fractional order derivative Kelvin model is established. The parameters of Kelvin model and fractional or- der derivative Kelvin model of axial plastic cumulative strain are optimized by genetic algorithm. By analyzing the correlation curve of calculation value and trial value of two models ; the fractional order derivative Kelvin model is more appropriate for calculating cumulative strain of saturated soft clay under cyclic loading
出处
《安徽理工大学学报(自然科学版)》
CAS
2016年第4期52-59,共8页
Journal of Anhui University of Science and Technology:Natural Science
关键词
饱和软黏土
开尔文模型
分数阶开尔文模型
遗传算法
saturated soft clay
Kelvin model
fractional order derivative Kelvin model
genetic algorithm