冻融黄土无侧限抗压强度的析因实验

(西安科技大学 建筑与土木工程学院,陕西 西安 710054)

冻融黄土; 无侧限抗压强度; 析因实验; 显著性分析

Factorial experiment on unconfined compression strength of freeze-thawing loess
WEI Yao,YANG Geng-she,YE Wan-jun,WANG Lei

(College of Civil and Architectural Engineering,Xi'an University of Science and Technology,Xi'an 710054,China)

freeze-thawed loess; unconfined compressive strength; factorial experiment; significance analysis

DOI: 10.13800/j.cnki.xakjdxxb.2019.0115

备注

自然界的黄土时刻经历着含水率、温度、围压、含盐量等多因素改变的耦合作用,为了明确多因素对黄土力学指标的影响关系。采用统计学原理及黄土力学试验的方法,对影响黄土无侧限抗压强度的因素进行析因实验,来研究多因素交互作用的效应性。通过不同含水率、冻融循环次数和冻结温度三因素的改变,试验黄土无侧限抗压强度的变化,依据析因设计原理进行显著性分析。结果 表明:黄土在10次冻融循环后强度只有未冻融的50%~70%之间,冻结温度作用下应变值基本处于2%~4%时,应力峰值都更早的出现。析因设计结果显示对无侧限抗压强度影响的显著性从大到小依次是冻融循环次数、含水率、冻结温度、含水率×冻融循环次数、二级交互作用、含水率×冻结温度、冻融循环次数×冻结温度。研究冻融循环对黄土力学指标的影响时,应模拟真实情况下的黄土环境,综合考虑多因素之间的交互作用。

The loess of nature has experienced the interaction of water content,temperature,confining pressure and salt content,and so on.In order to clarify the influence of multiple factors on the mechanical parameters of loess,the factors influencing the unconfined compressive strength of loess were analyzed by statistical method and the mechanics test of loess,and the effect of multi-factor interaction was studied.The change of the unconfined compressive strength of the tested loess was analyzed by the change of the three factors,such as the different water content,the number of freeze-thaw cycles and the freezing temperature,and the significance analysis was carried out according to the principle of factorial design.The results show that the stress of the loess is only 50%~70% after 10 freezing and thawing cycles,the strain is 2%~4% at the freezing temperature,and the effect of unconfined compressive strength is number of freeze-thaw cycle times,water content,freeze temperature and water content×freeze-thaw cycle times,secondary interaction and water content×freeze temperature and freeze-thaw cycle times×freeze temperature.In the study of the effect of freeze-thaw cycle on the mechanical parameters of loess,the loess environment under the real situation should be simulated,and the interaction between multiple factors should be considered synthetically.