云南文山膨胀土强度参数变化规律初探  

Preliminary Study on Strength Parameters of Expansive Soil in Wenshan Prefecture of Yunnan Province

作　　者：刘伟[1] 尹琼[1] 方娜 李宛鸿 LIU Wei;YIN Qiong;FANG Na;LI Wanhong(Mining Engineering Faculty, Kunming Metallurgy College, Kunming 650033,China;Yunnan Geological Engineering Survey and Design Institute, Kunming 650041,China)

机构地区：[1]昆明冶金高等专科学校矿业学院,云南昆明650033 [2]云南地质工程勘察设计研究院,云南昆明650041

出　　处：《昆明冶金高等专科学校学报》2019年第1期6-10,25,共6页Journal of Kunming Metallurgy College

基　　金：昆明冶金高等专科学校科研基金项目:云南文山盆地膨胀土裂隙分布规律与含水率的关系(2015XJYB001)

摘　　要：不同性质或载荷状态的膨胀土在胀缩过程中强度参数降幅有明显差异。为初步探讨强度参数降幅与所受载荷、土体自身膨胀力之间的关系,取样自云南文山盆地普者黑机场区域膨胀土,进行不同载荷状态下的强度参数降幅实验及膨胀力与强度降幅相关性实验。实验结果:载荷增加,强度参数降幅随之减少,如内聚力C值、内摩擦角φ值降幅分别由5 kPa下的72.32%、77.22%减少至40 kPa下的34.93%、27.42%;膨胀力与强度参数降幅随着载荷的增加,渐趋正相关。表明:载荷对强度降幅有控制作用,主要为对裂隙发育的抑制;膨胀力与强度参数降幅的相关性与载荷状态有关;载荷和膨胀力的比值与强度降幅总体趋势上表现为负相关。There are obvious differences in strength parameters of expansive soils with different properties or loading conditions during expansion and contraction. In order to preliminarily explore the relationship between the strength parameter reduction and the load and the swelling force of the soil itself, the strength parameter reduction experiments and the correlation experiments between the swelling force and the strength reduction were carried out. The experimental results show that with the increase of load, the decrease amplitude of strength parameters declines, such as cohesion C value and internal friction angle decreased from 72.32% and 77.22% at 5 kPa to 34.93% and 27.42% at 40 kPa, respectively;and the decrease amplitude of expansive force and strength parameter gradually positively correlated with the increase of load. The results show that the load has a controlling effect on the strength drop, mainly on the inhibition of fracture development;the correlation between the expansion force and the strength parameter drop is related to the load state;the ratio of the load and the expansion force is negatively related to the overall trend of the strength drop.

关 键 词：膨胀土 强度参数 载荷状态 膨胀力 

分 类 号：TU443[建筑科学—岩土工程]