新型非饱和黄土拉压试验仪的研制与应用  

Development and application of new typetension and compression tester for unsaturated loess

作　　者：尹思雨 王晓静[1] 汪凯凯 武少鹏 YIN Siyu;WANG Xiaojing;WANG Kaikai;WU Shaopeng(College of Geology and Environment,Xi′an University of Science and Technology,Xi′an 710054,China;School of Geology and Mineral Engineering,Xinjiang University,Urumqi 830046,China)

机构地区：[1]西安科技大学地质与环境学院,陕西西安710054 [2]新疆大学地质矿产工程学院,新疆乌鲁木齐830046

出　　处：《人民长江》2021年第10期225-230,共6页Yangtze River

基　　金：国家青年科学基金项目(41402264);西安科技大学博士(后)基金项目(2013QDJ038)。

摘　　要：土体的抗拉强度是研究张拉破坏特性的理论基础,目前室内测试方法多样但均存在一定局限性,因而较难准确获得土体真实的抗拉强度。对比分析了现有的试验装置和试验方法,将原有试验仪器按模块进行分块对比并补足,研制出新型单轴拉压仪和配套的制样装置,并根据自制仪器开展了临潼地区Q_(2)原状黄土的抗拉强度试验。结合黄土抗拉强度产生机制,分析了非饱和黄土的破坏形态与破坏机理。试验结果表明:非饱和黄土的抗拉强度随含水率的增大以幂函数关系减少;在不同高径比试验研究中,非饱和黄土的抗拉强度受试样尺寸与形状的影响,具有尺寸效应,在一定含水率条件下,抗拉强度与高径比呈负指数关系,当高径比大于2.64时,尺寸效应消失。The tensile strength of soil is the theoretical basis for studying the characteristics of tensile failure.At present,although indoor testing methods of tensile strength were various,most of them have certain limitations,so it is difficult to accurately obtain the true tensile strength of soil.In this paper,we compared and analyzed the existing test devices and test methods,so improved the traditional test devicesand finally develop a new type of uniaxial tension and compression tester and matching sample preparation devices.Based on the new device,we carried outa tensile strength test on the undisturbed Q_(2)loess in Lintong area.The failure pattern and mechanism of unsaturated loess were analyzed by combining with the generation mechanism of the tensile strength of the loess.The test results indicated that the tensile strength of unsaturated loess decreased as a power function with the increase of water content.Furthermore,the tensile strength of unsaturated loess was affected by the sample size and shape under different height-diameter ratio,which had an obvious size effect.The relationship between tensile strength and height-diameter ratio exhibited a negative exponential law ina certainwater content.When the height-diameter ratio was greater than 2.64,the size effect disappeared.

关 键 词：拉压试验仪 非饱和黄土 新型拉伸仪 抗拉强度 尺寸效应 

分 类 号：P642[天文地球—工程地质学]