摘要
在总结诸多大型浸水现场试验成果的基础上，提出了一些关于湿陷性评价方法和剩余湿陷量合理控制等问题的新认识，目的是为了修正自重湿陷性黄土场地的自重湿陷量计算值与其实测值之间的差异，并减小地基处理深度。在获取自重湿陷量的计算值时，引进了一个深度修正系数ξ，使自重湿陷量和湿陷量的计算值接近实测值，这在一定程度上降低了较深部位黄土的剩余湿陷量。在获取湿陷量计算值时，提出了扩大湿陷系数阈值（0．015）的方案，并与深度修正系数ξ联合使用，达到了扩大湿陷量的计算值和降低较深土层的剩余湿陷量的目的。提出了大厚度自重湿陷性黄土场地的湿陷临界深度的概念，通过若干资料将其初步确定为20-25m之间，结合深度修正系数和扩大湿陷系数阈值方法，使用湿陷临界深度概念，可以更为有效地降低较深土层的剩余湿陷量。新的研究思路可为自重湿陷性黄土场地的类似工程和黄土规范的修订提供一定的参考。
Based on summarized results of several large-scale soaking tests, some new recognition about methodology of collapsibility evaluation and reasonable limit of remnant collapse are proposed to modify difference between computed collapse under overburden pressure and measured value, and to decrease the collapsible loess treatment depth. When acquiring the computed collapse under overburden pressure, a depth correction factor ξ is suggested to make computed collapse under overburden pressure and the computed collapse of laboratory tests approximate measured collapse of in-situ tests; and it will decrease remnant collapse of collapsible loess in deeper position in some degree. When obtaining computed collapse, a scheme amplifying coefficient threshold of collapsibility （0.015） is presented, the method combined with depth correction factor ξ can reach the expected goal to enlarge the computed collapse and decrease remnant collapse of deeper collapsible loess. The conception ＂critical collapsibility depth＂ of dead weight collapse loess with heavy section is proposed; the critical collapsibility depth is set as 20-25 m temporarily according to some test data. In combination with the method of depth correction factor and amplifying coefficient threshold of collapsibility, the conception of critical collapsibility depth can decrease effectively remnant collapse of collapsible loess. The research results will be of interest for similar projects in the area of dead weight collapse loess and be useful to revise ＂standard for building construction in collapsible loess regions＂.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2014年第4期998-1006,共9页
Rock and Soil Mechanics
基金
国家电网公司科学技术项目(No.SGKJJSKF[2008]656)
国家自然科学基金项目(No.11272353
No.11272354)
关键词
湿陷性黄土
自重湿陷量的计算值
湿陷量的计算值
剩余湿陷量
深度修正系数
湿陷系数阈值
collapsible loess
computed collapse under overburden pressure
computed collapse
remnant collapse
depth correction factor
threshold of collapsibility coefficient
