农业工程学报2012，Vol.28Issue(5)：241-245,5.DOI:10.3969/j.issn.1002-6819.2012.05.040
干湿效应下崩岗区岩土抗剪强度衰减非线性分析
Effects of drying and wetting on nonlinear decay of soil shear strength in slope disintegration erosion area
摘要
Abstract
Red soils derived from granite in slope disintegration areas are influenced significantly by wetting and drying. Effects of wetting and drying changes on decay of soil shear strength in slope disintegration areas were investigated in laboratory by direct shearing test. Five soil wetting and drying treatments (drying 48 h, drying 24 h, natural water content, wetting 30 s, wetting 60 s) were tested. Experimental data indicated that shear strength indices (soil cohesive force and internal frictional angle) declined with drying and wetting levels, and they reached to the maximum at the water content of about 13%. The relationship between shear strength indices and drying and wetting levels could be simulated to linear function before strength peak and to first order exponential decay function after the peak; Shear strength was dominantly affected by crack evolution during drying period, while matric suction was the main factor for shear strength decline. Finally, the drying and wetting effect on development of slope disintegration was discussed in the paper.关键词
土壤/抗剪强度/非线性分析/崩岗侵蚀区/峰值强度/干湿效应Key words
soils/ shear strength/ nonlinear analysis/ slope disintegration area/ peak strength/ drying and wetting effect分类
农业科技引用本文复制引用
张晓明,丁树文,蔡崇法..干湿效应下崩岗区岩土抗剪强度衰减非线性分析[J].农业工程学报,2012,28(5):241-245,5.基金项目
中央高校基本科研业务费专项资金资助(2009QC035) （2009QC035）
华中农业大学科研启动资金(52204-08077) （52204-08077）
“十二五”国家科技支撑计划“农田水土保持关键技术研究与示范(2011BAD31B00)” （2011BAD31B00）
