| 引用本文: | 刘武江,段青松,杨松,等.不同改良剂对红壤-土水特征曲线及吸附强度的影响研究[J].灌溉排水学报,0,():-. |
| LIU Wujiang,DUAN Qingsong,YANG Song,et al.不同改良剂对红壤-土水特征曲线及吸附强度的影响研究[J].灌溉排水学报,0,():-. |
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| 摘要: |
| 【目的】向边坡土壤内加入改良剂会对土体水分产生较大影响，揭示此过程中土水特征曲线及吸附强度的变化规律可为采用改良剂进行边坡治理提供依据。【方法】通过测定不同配比的糯米胶、木纤维、糯米胶/木纤维混施的红壤土的基质吸力ψ和体积含水率θv，绘制土水特征曲线并分析典型特征参数变化；采用直剪试验测定不同改良剂红壤饱和状态的内摩擦角φ，结合Fredlund双应力变量抗剪强度理论，分析不同改良剂对红壤吸附强度τψ的影响。【结果】（1）糯米胶和木纤维能提高土体饱和含水率θs，混合改良剂反之；糯米胶和混合改良剂会降低土水特征曲线的残余含水率θr，木纤维只有在较低或较高掺量时才会降低残余含水率，反之增高；3种改良剂均能提高土水特征曲线的进气值ψa，混合改良剂>糯米胶>木纤维；糯米胶会降低土水特征曲线的残余值ψr，木纤维反而增加残余值，混合改良剂介于二者之间且高于素土；糯米胶的土水特征曲线斜率|k|最大，其次是混合改良剂和木纤维。（2）不同改良剂红壤随θv降低，ψ增加，吸附强度τψ增大，抗剪强度随ψ增加的速率减小。在23.73%~30.76%体积含水率区间，2.5%纤维和5%纤维的吸附强度相对较大，其次是素土、5%混合和2.5%混合，最后是2.5%胶、5%胶和0.5%胶。【结论】（1）糯米胶主要影响|k|值，致使土体水分散失速率加快；木纤维对θs、θr、及ψr的影响最大，土体保水性好，水分不易流失；混合改良剂以提高ψa为最优，土体初期（边界效应阶段）不易失水，中后期受糯米胶成分的影响，持水能力减弱。（2）不同改良剂增大τψ的效果由强到弱依次为：木纤维>糯米胶>混施。 |
| 关键词: 土壤改良剂; 红壤; 基质吸力; 土水特征曲线; 吸附强度 |
| DOI： |
| 分类号:S284 |
| 基金项目:(41867038);国土资源部公益性行业科研专项经费(201511003-3);国土资源部“西南多样性区域土地优化配置与生态整治科技创新团队”开放基金(YNTD2018KF05) |
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| Effects of Different Modifiers on Soil-water Characteristic Curve and Adsorption Strength of Red Loam Soil |
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LIU Wujiang1, DUAN Qingsong2, YANG Song2, XIONG Shoude3, BAO Ruiqin4, LI Liyang5,6,6,7, ZHANG Chuan8,9
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1.Yunnan Academy of Agricultural Engineering;2.College of Water Conservancy,Yunnan Agricultural University;3.Yunnan Geological Engineering Survey and DesignResearch Institute Limited Company;4.College of Resources and Environment,Yunnan Agricultural University;5.Yunnan Yuanke Land Consolidation and Rehabilitation and Planning &6.amp;7.Design Limited Company;8.College of Hydraulic Engineering, Yunnan Agricultural University;9.Research Center for Transition Development and Rural Revitalization of Resource-based Cities in China, China University of Mining and Technology
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| Abstract: |
| 【Objective】 Adding modifiers into slope soil will have a great influence on soil moisture. Revealing the soil-water characteristic curve and the change rule of adsorption strength during this process can provide a basis for slope treatment with modifiers.【Methods】 By measuring the matrix suction ψ and volume water content θv of red loam soil mixed with glutinous rice gum, wood fiber and glutinous rice gum/wood fiber with different content ratios, the soil-water characteristic curve was drawn and the changes of typical characteristic parameters were analyzed. The internal friction angle φ of the saturated state of red loam soil of different modifiers was determined by direct shear test, and the influence of different modifiers on the adsorption strength τψ of red loam soil was analyzed by combining the theory of Fredlund double stress variable shear strength.【Results】 (1) glutinous rice gum and wood fiber could increase the saturated water content θs of the soil, and mixed modifier vice versa; Glutinous rice gum and mixed modifier will reduce the residual water content θr of the soil-water characteristic curve, and wood fiber will only reduce the residual water content at a lower or higher content, and vice versa. The three modifiers could increase the inlet value ψa of the soil-water characteristic curve, and the mixed modifier > glutinous rice gum > wood fiber; Glutinous rice gum will reduce the residual value ψr of the soil-water characteristic curve, wood fiber will increase the residual value, and the mixed modifier is in between and higher than that of plain soil. The slope |k| of the soil-water characteristic curve of glutinous rice gum is the largest, followed by mixed modifier and wood fiber. (2) The red soil of different modifiers decreases with θv, the ψ increases, the adsorption strength τψ increases, and the shear strength decreases with the increase of ψ. In the range of 23.73%~30.76% volume water content, the adsorption strength of 2.5% fiber and 5% fiber is relatively large, followed by plain soil, 5% mixed and 2.5% mixed, and finally 2.5% glue, 5% glue and 0.5% glue.【Conclusion】 (1) Glutinous rice gum mainly affects the |k| value, resulting in accelerated the loss rate of soil water dispersion; Wood fiber has the greatest influence on θs, θr, and ψr, and the soil has good water retention and is not easy to lose water; Mixing the modifier to improve ψa is the best, the soil is not easy to lose water in the early stage (boundary effect stage), and the water-holding capacity is weakened by the influence of glutinous rice gum components in the middle and late stages. (2) The effect of different modifier on increasing τψ is: wood fiber> glutinous rice gum > mixed application. |
| Key words: Soil amendments; Red loam; Matric suction; Soil-water characteristic curve; The adsorption strength |
