摘要
【目的】植物的不同生长时间会对根系数量,根茎粗细产生影响,进而影响加筋土的力学性能以及边坡稳定性,研究降雨条件下不同生长时间根系对边坡稳定性的影响可以更好地指导根系护坡工程设计。【方法】采用PLAXIS 3D有限元软件对6种不同生长时间的根系护坡进行模拟。【结果】不同生长时间的根系长度均无法穿过边坡滑移面,随着根系生长时间的增加,边坡最小安全系数增大幅度较小,即根系生长时间增加无法显著提高边坡整体稳定性,但降雨条件下的边坡土体最大总位移、最大水平位移及最大竖向位移均不断减小,其中根系限制水平方向位移比竖直方向位移更加有效。护坡植物根系生长前9个月,对增强边坡土体降雨条件下位移的控制效果更加显著,此后根系生长时间的增加对边坡土体位移控制效果的增加幅度减小。针对边坡位移要求较高的护坡工程,提出根系结合抗滑桩的联合护坡方式。根系结合单道抗滑桩可大幅度降低降雨条件下的边坡土体位移。当采用联合护坡时,降雨后边坡最大位移为1.47 mm,相比仅根系护坡时的5.03 mm减小了70.78%,相比仅抗滑桩护坡时的1.54 mm减小了4.55%。同时,边坡最小安全系数由根系护坡时的1.174增加到1.399,边坡安全性得到显著提高。此外,边坡坡面失稳滑动面由坡脚位置上升至抗滑桩顶部,有效增强边坡稳定性。【结论】研究成果确定了根系不同生长阶段对边坡稳定性的影响,可为根系护坡工程的相关设计和研究提供参考,为根系护坡的稳定性评价提供依据。
【Objective】Different growth stages of plants affect the amounts of roots and the thickness of rhizomes,thus affecting the mechanical properties of reinforced soil and the slope stability.The research on the influence of different growth stages of root system on slope stability under rainfall conditions will better guide the engineering design of slope.【Method】To study the effect of different root growth stages on the slope stability under rainfall conditions,six types of slope protection based on plant roots at different growth stages was simulated by using PLAXIS 3D software.【Result】The simulation resulted show that the root length cannot pass through the slip surface of the slope at different growth stages.As the root growth stages increase,the minimum safety factor of the slope increases,while the increase rate is small,i.e.,the slope’s overall stability cannot be significantly improved.However,the maximum total displacement,maximum horizontal displacement and maximum vertical displacement keep decreasing with the growth of roots under rainfall conditions,among which horizontal displacement control performs better than vertical control.The influence of root system of slope protection plants on the displacement control of the slope soil under rainfall conditions is more significant within the first nine months of growth.After growth of nine months,the influence of root growth stage on the displacement control effect of slope soil decreases.As for the higher demanding slope protection project,the combination of root system with anti-slide pile is proposed.The research shows that laying of single row of anti-slide piles combined with vegetation protection is able to control slope displacement under rainfall conditions.When combined slope protection is used,the maximum displacement of the slope after rainfall is 1.47 mm,which decreases by 70.78%compared with that of 5.03 mm when only the root slope protection is used,and decreases by 4.55%compared with that of 1.54 mm when only the anti-slide pile is
作者
嵇晓雷
尹鹏
JI Xiaolei;YIN Peng(College of Construction Engineering,Jiangsu Open University,Nanjing 210036,Jiangsu,China;College of Civil Engineering,Nanjing Forestry University,Nanjing 210037,Jiangsu,China;College of Civil Engineering,Central South University of Forestry and Technology,Changsha 410004,Hunan,China)
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2020年第12期144-150,178,共8页
Journal of Central South University of Forestry & Technology
基金
江苏高校自然科学基金项目(18KJB220001)
江苏“六大人才高峰”项目(JZ-018)
住房城乡建设部科学技术项目计划(2016-K4-020)。
