• 首页 | 期刊简介 | 编委会 | 投稿须知 | 下载专区 | 联系我们 | English
原状土e-lgp曲线的S形函数表达及简化加载固结试验方法
An analysis of S-shaped function expression of e-lgp curve and a simplified consolidation method for undisturbed soil
投稿时间: 2017-04-08  最后修改时间: 2017-07-23
DOI:
中文关键词:  原状细粒土  e-lgp曲线  S形曲线函数  先期固结压力  正常固结状态带  简化固结试验
英文关键词:undisturbed fine-grained soil  e-lgp curve  S-shaped curve function  preconsolidation pressure  normal consolidation status zone  simplified consolidation test
基金项目:国家重点基础研究发展计划(973计划)
作者单位E-mail
赵明志 西南交通大学 zmz2008.happy@163.com 
罗强 西南交通大学 lqrock@home.swjtu.edu.cn 
摘要点击次数: 20
全文下载次数: 
中文摘要:
      为能够较为合理地确定土体压缩参数并简化固结试验加载过程,结合京沪高铁李窑试验段地基原状细粒土样标准固结试验数据,对比分析了多项式和三种S形曲线函数在描述原状土e-lgp曲线发展规律时的差异性,探讨了先期固结压力的合理计算原则,提出了简化加载级数的固结试验方法。结果表明,多项式函数易受数据波动而导致整体拟合偏差,S形曲线函数的待定参数可良好稳定地反映曲线最小曲率半径点和直线段斜率,为较理想的e-lgp曲线数学函数表达式;通过分析Arvidsson法、Gregory法和Casagrande法确定先期固结压力时的不同取值原则,获得了先期固结压力值的变化区间,提出土体由超固结过渡到欠固结状态时存在正常固结状态带的概念,用于判断土体固结特性较为客观合理;利用土体初始孔隙比和两级或三级荷载下的变形值可确定S形曲线函数待定参数,据此建立了简化加载级数的固结试验方法。研究成果为准确判定土体固结特性、快速获取土体压缩参数提供了理论指导。
英文摘要:
      The clay samples of Liyao test site on Beijing-Shanghai high-speed railway were taken to conduct the oedometer test to discuss the method to obtain the compressibility parameters of clay samples reasonably and to simplify the loading process of oedometer test. The differences between polynomial function and other three kinds of S-shaped functions were analyzed when they were used to describe the compression curves. Moreover, the principal to calculate the preconsolidation stress was discussed and the simplified oedometer test method was put forward. The conclusions were made as follows. The fitting effect of polynomial, which is easily affected by the test data fluctuation, is verified. The undetermined parameters of the S-shaped curve function can steadily reflect the point coordinate of minimum curvature radius and the slope of straight line. The error of calculated compression modulus in pressure range which is in common use stays less than 10%. Therefore, the S-shaped curve function is an ideal expression of e-lgp curve. Based on the different criterion for calculating the preconsolidation pressure of Arvidsson method, Gregory method and Casagrande method, a variation range for preconsolidation press can be got. Furthermore, the concept of normal consolidation status zone, which is reasonable for judging the consolidation characteristic, was put forward. This zone is existed when soil transfer from over-consolidation to under-consolidation. The undetermined parameters of S-shaped function can be ascertained by the soil initial void ratio and the deformation under two-level or three-level load. Thus, a simplified consolidation method is established. The research provides theoretical guidance for judging the consolidation characteristic precisely and obtaining the compression physical quantity rapidly.
查看全文  查看/发表评论  下载PDF阅读器
关闭

版权所有:《实验力学》编辑部
您是本站第 1575642 位访问者,今日一共访问83次,当前在线人数: 67
技术支持:本系统由北京勤云科技发展有限公司设计