矿渣和石灰改良膨胀土力学性能直剪试验研究  

Direct shear test study on mechanical properties of slag and lime improved expansive soil

作　　者：黄华 黄中文 蓝天助 HUANG Hua;HUANG Zhongwen;LAN Tianzhu(Guangxi Zhuang Autonomous Region Expressway Development Center,Nanning 530022,China;Western Guangxi Expressway Development Center,Nanning 530011,China;Guangxi Transportation Science&Technology Group Co.,Ltd.,Nanning 530007,China)

机构地区：[1]广西壮族自治区高速公路发展中心,广西南宁530022 [2]广西壮族自治区桂西公路发展中心,广西南宁530011 [3]广西交科集团有限公司,广西南宁530007

出　　处：《粘接》2025年第5期64-67,72,共5页Adhesion

基　　金：广西重点研发计划项目(项目编号:桂科AB23075184)。

摘　　要：将膨胀土经矿渣石灰改良后进行资源化利用,可以有效减少膨胀土弃渣的产生,但采用矿渣石灰改良膨胀土的力学特性尚不清楚。为此,采用直剪试验,对不同养护龄期的改良膨胀土试样抗剪强度特性进行研究。结果表明,矿渣石灰改良膨胀土试样养护28 d后的粘聚力达到了未改良膨胀土粘聚力的5倍以上,内摩擦角达到了未改良膨胀土内摩擦角的1.39倍以上;随着上覆应力的增加,矿渣石灰改良试样的脆性指数及剪胀角逐渐减小,在剪切过程中的变形行为逐渐由剪胀向剪缩过渡;未改良膨胀土试样的剪切行为是:剪缩-硬化,但经矿渣石灰改良后试样的剪切行为变为:剪胀-软化,研究结果可为膨胀土的改良利用提供理论参考。The expansive soil slag can be effectively reduced by the resource utilization of expansive soil after slag lime improvement,but the mechanical properties of expansive soil modified by slag lime are not clear.Therefore,the shear strength characteristics of improved expansive soil samples with different curing ages were studied by direct shear test.The results showed that the cohesion of the slag-lime modified expansive soil sample after 28 days of curing reached more than 5 times that of the unimproved expansive soil.The internal friction angle was more than 1.39 times of the internal friction angle of the unimproved expansive soil.With the increase of the overlying stress,the brittleness index and dilatation angle of the slag-lime improved sample gradually decreased,and the deformation behavior of the slag-lime improved sample gradually transformed from dilatancy to shear contraction.The shear behavior of the unimproved expansive soil sample was shear-hardening,but the shear behavior of the sample after the improvement of slag lime became dilatation-softening,and the research results can provide a theoretical reference for the improvement and utilization of expansive soil.

关 键 词：矿渣石灰 膨胀土改良 抗剪强度 剪切行为 

分 类 号：TQ177.2[化学工程—硅酸盐工业]