张展羽,李文杰,王策,陈于,范世敏.多级干湿循环对农田土壤干缩裂缝演变特征的影响[J].农业机械学报,2016,47(12):172-177,252.
Zhang Zhanyu,Li Wenjie,Wang Ce,Chen Yu,Fan Shimin.Effects of Dry—Wet Cycles on Evolution Characteristics of Farmland Soil Desiccation Cracks[J].Transactions of the Chinese Society for Agricultural Machinery,2016,47(12):172-177,252.
摘要点击次数: 705
全文下载次数: 449
多级干湿循环对农田土壤干缩裂缝演变特征的影响   [下载全文]
Effects of Dry—Wet Cycles on Evolution Characteristics of Farmland Soil Desiccation Cracks   [Download Pdf][in English]
投稿时间:2016-05-12  
DOI:10.6041/j.issn.1000-1298.2016.12.021
中文关键词:  土壤  干缩裂缝  干湿循环  演变特征  几何形态特征
基金项目:国家自然科学基金项目(51579069、51179050)、江苏省高校优势学科建设工程项目(YS11001)和高等学校学科创新引智计划(111计划)项目(B12032)
作者单位
张展羽 河海大学 
李文杰 河海大学 
王策 河海大学 
陈于 河海大学 
范世敏 河海大学 
中文摘要:为研究多级干湿循环条件下农田土壤干缩裂缝的演变特征,在室内试验基础上,结合数字图像处理技术对裂缝几何形态特征进行了统计与定量分析。结果表明,干湿循环后,土壤开裂位置不变,增湿过程中裂缝闭合规律也大致相似,但干燥初期裂缝开裂规律受第1级干湿循环影响明显。第1级干湿循环后,裂缝面积率在含水率为20%~30%时增速降低,约90%的裂缝长度发育集中在含水率大于30%时,连通性指数在含水率大于14%时近似匀速增大。随着干湿循环级数的增加,土壤开裂含水率逐渐减小,而干缩稳定时裂缝网络连通性有所增强,但裂缝网络形态大致相似,裂缝总长也保持稳定。此外,裂缝宽度与土壤开裂程度均呈递减趋势,且各裂缝的宽度逐渐趋向统一,将对裂缝优先流有所遏制,有利于土壤水分的均匀入渗。
Zhang Zhanyu  Li Wenjie  Wang Ce  Chen Yu  Fan Shimin
Hohai University,Hohai University,Hohai University,Hohai University and Hohai University
Key Words:soil  desiccation crack  dry—wet cycle  evolution characteristics  geometric and morphological characteristics
Abstract:Aiming to investigate the evolution characteristics of soil desiccation cracks with multiple dry—wet cycles, laboratory tests were carried out to quantitatively analyze the geometric and morphological characteristics of cracks. It indicated that the soil was cracked at the same position during each dry—wet cycle, and behaved a similar crack closure law. The crack ratio was decreased slowly before moisture content was increased to 12%, and decreased rapidly when moisture content reached 18%, while it was remained stable when moisture content was between 12% and 18%. Both the crack length density and connectivity index were decreased quickly after got a critical moisture content, which was reduced with the increase of dry—wet cycles, respectively, and kept constant before that. However, the initial cracking law was greatly affected by the first dry—wet cycle. Since the second cycle, the acceleration of crack ratio was decreased when the moisture content was changed from 30% to 20%, and about 90% of the crack was developed before moisture content reduced to 30%, and the connectivity index was increased at a constant speed when moisture content was larger than 14%. When the dry—wet cycles were increased, it can be concluded that: the crack morphology and length were kept stable;the cracking moisture content was reduced and the connectivity of crack network was enhanced, but there were no obvious differences;the average crack width and stable crack ratio were decreased gradually, and the average width tended to be the same, which weakened the crack preferential. The research result has practical guiding for cracked soil irrigation.

Transactions of the Chinese Society for Agriculture Machinery (CSAM), in charged of China Association for Science and Technology (CAST), sponsored by CSAM and Chinese Academy of Agricultural Mechanization Science(CAAMS), started publication in 1957. It is the earliest interdisciplinary journal in Chinese which combines agricultural and engineering. It always closely grasps the development direction of agriculture engineering disciplines and the published papers represent the highest academic level of agriculture engineering in China. Currently, nearly 8,000 papers have been already published. There are around 3,000 papers contributed to the journal each year, but only around 600 of them will be accepted. Transactions of CSAM focuses on a wide range of agricultural machinery, irrigation, electronics, robotics, agro-products engineering, biological energy, agricultural structures and environment and more. Subjects in Transactions of the CSAM have been embodied by many internationally well-known index systems, such as: EI Compendex, CA, CSA, etc.

   下载PDF阅读器