应变式直剪仪与微型十字板剪切仪测定土壤抗剪强度的对比分析  

Comparative Analysis of Soil Shear Strength Measured by Strain-Controlled Direct Shear Apparatus and Micro-Vane Shear Apparatus

作　　者：徐圣贤 张庆玮 李雯玲 陈伟杰 陈紫燕 赵成龙 Xu Shengxian;Zhang Qingwei;Li Wenling;Chen Weijie;Chen Ziyan;Zhao Chenglong(College of Soil and Water Conservation Science and Engineering/Institute of Soil and Water Conservation,Northwest A&F University,Yangling,Shannxi 712100,China;College of Natural Resources and Environment,Northwest A&F University,Yangling,Shannxi 712100,China)

机构地区：[1]西北农林科技大学水土保持科学与工程学院(水土保持研究所),陕西杨凌712100 [2]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《水土保持研究》2024年第4期205-213,共9页Research of Soil and Water Conservation

基　　金：国家自然科学基金“黄土区坡面细沟间侵蚀粒径分选动力学过程研究”(42107362)。

摘　　要：[目的]分析两种仪器(应变式直剪仪与微型十字板剪切仪)测得的土壤抗剪强度指标(土壤黏聚力值c、内摩擦角φ、土壤剪切力τ)特征,并建立直剪仪测得的c和φ与十字版仪测得的τ之间的函数关系,以期深化对土壤抗剪强度的认识,提高土壤抗剪强度指标测定效率。[方法]选取黄土高原3种典型质地类型土壤(杨凌黏黄土、安塞黄绵土、定边沙黄土),每种土壤设5个含水量梯度(12%,16%,20%,24%,28%),分别用上述两种仪器测定不同处理下土壤抗剪强度指标c,φ和τ,探究了3指标对土壤质地、土壤含水量的响应特征以及3指标间的函数关系。[结果](1)试验条件下,c值在16.88~27.12 kPa范围,φ值在5.03°~21.30°范围,τ值在1.76~7.72 kPa范围变化;(2)不同土壤类型下,c和τ均随含水量的增大呈现先增大后减小趋势,而φ随含水量增大呈现逐渐降低趋势;(3)总体来看,安塞黄绵土的τ,c,φ值略高于定边沙黄土,但它们均显著大于杨凌黏黄土。(4)3种土壤类型下,微型十字板剪切仪所测定的τ值与直剪仪测定的c值均具有较强的线性相关关系(R 2>0.90);而φ值与τ值间并无显著相关关系。如不考虑土壤类型差异,τ与c之间仍有较强的相关性,关系式为c=1.59τ+14.10(R 2=0.51,p<0.01)。[结论]应变式直剪仪测得的黏聚力c值和微型十字版仪测得的土壤剪切力τ值对土壤质地、含水量的响应相似,且二者有显著的相关关系,在一定条件下可以用快速便捷的微型十字版仪测得的τ值估算原本需用直剪仪测的c值。研究结果可为野外极端条件下提高土壤抗剪强度测定效率方面提供参考。[Objective]This study aims to analyze the characteristics of soil shear strength parameters obtained by strain-controlled direct shear apparatus and micro-vane shear apparatus,respectively(soil cohesive force c,internal friction angleφ,and soil shear forceτ),and then establish the relationship between c,φandτ.This can deepen the understanding of soil shear strength,and have important significance for improving the efficiency of soil shear strength measurement.[Methods]Three typical texture types of soil(Yangling clayey soil,Ansai loessial soil,Dingbian sandy soil)from the Loess Plateau,and five levels of soil moisture(12%,16%,20%,24%and 28%)were designed to obtained their soil shear strength using the above mentioned apparatuses.The responses of soil shear strength to soil types and soil moisture,as well as relationships between c,φandτwere then analyzed.[Results](1)Under experiment conditions,the values of c,φandτrange between 16.88~27.12 kPa,5.03°~21.30°,1.76~7.72 kPa,respectively.(2)In the three soil types,the c andτfirstly increase and then decrease with the increase of soil moisture.While,theφdecreases gradually with the soil moisture increase.(3)The c,τ,andφof Ansai loessial soil are similar or slightly higher than those in Dingbian sandy soil,while they are significantly higher than those in Yangling clay soil.(4)In the three types of soil,there is a significant linear correlation between theτand c(R 2>0.93),while there is no significant correlation between theφandτ.Without considering the difference of soil type,there is still a strong linear correlation betweenτand c,and its relation can be described by c=1.59τ+14.10(R 2=0.51,p<0.01).[Conclusion]The responses of c to soil type and soil moisture were similar to that ofτ,and a significant relation are found between c andτ.It implies that researchers can useτ,conveniently obtained by micro-vane shear apparatus,to assess c,obtained by strain-controlled direct shear apparatus slowly under some conditions.The results can provide reference

关 键 词：应变式直剪仪 微型十字板剪切仪 剪切力 黏聚力 内摩擦角 

分 类 号：S152.9[农业科学—土壤学]