摘要
为了进一步探讨砒砂岩区沙棘植物护坡的力学效应及其影响因素,研究选取该区域内4年生沙棘根部对其进行室内单根拉伸试验,选取根系自身影响因素直径和根长、外界影响因素拉伸速率,分别以此为变量,探讨根系抗拉力学特性,并结合SPSS软件对其影响因素进行综合分析。结果表明:抗拉力随根系直径的增加而增加,抗拉强度随根系直径的增加而逐渐减小;同一直径级下,随着根长和拉伸速率的增大,抗拉力和抗拉强度都相应减小;应力—应变曲线描述的沙棘单根受拉伸变形过程表现出随根系直径、根长的增加,变形趋势逐渐减弱,然而随着加载速率的增加,并没有明显变化规律。综合分析表明三种影响因素对沙棘单根抗拉特性的影响大小依次是根系直径>根长>加载速率,结合沙棘具备根系密而发达的特点,证明在冲刷速率较大的情况下,沙棘根系能充分利用缠绕在一起的根系、多而密集的短根能够固持泥土,对这一区域的水土保持具有一定的意义。
To further explore the mechanical effect and influencing factors of vegetation revetment in the soft rock area.This study selected four-year-old Hippophae rhamnoides Linn root in soft rock area,The factors such as the diameter,root length of the root system,the loading rate of the external influencing factors were selected as the variables,and the tensile properties of the roots were discussed.In addition,the data were analyzed synthetically by SPSS.The results showed that the tensile resistance and the tensile strength of Hippophae rhamnoides Linn root had power relations with root diameter,and had negatively correlated with the root length and loading rate.The stress-strain curve decreased with the increase of root diameter and root length but no obvious change was observed with the increase of loading rate.The comprehensive analysis of the three influencing factors above showed that the importance of these factors followed a descending order as the root diameter>the length of the root>the loading rate.Combined with the characteristics of the dense and well developed Hippophae rhamnoides Linn roots,it was also proved that the Hippophae rhamnoides Linn roots can completely utilize its root system and intensive short root to fix the soil in the case of large erosion rate.This study is of great importance to the conservation of soil and water in this area.
作者
雷菁花
杨方社
马艺坤
LEI Jinghua;YANG Fangshe;MA Yikun(Tongchuan Branch of Shaanxi Land Engineering Construction Group,Co.,Ltd.,Xi’an 710075,China;College of Urban and Environment Sciences Northwestern University,Xi’an 710075,China)
基金
国家自然基金项目(51279163).
关键词
砒砂岩区
抗拉力
抗拉强度
应力—应变曲线
soft rock area
tensile resistance
tensile strength
stress-strain curve
作者简介
雷菁花(1993-),女,陕西渭南人,硕士,助理工程师,从事水土保持工作。E-mail:1213145572@qq.com
