摘要
针对黄土滑塌高边坡治理加固中的空间受限、高填方填筑及水平位移变形等问题,提出了有限填土加筋土-框锚组合体系。以陕西铜川某高陡边坡为背景,首次开展了组合体系协同作用的物理模型试验,探讨了框架梁墙面水平位移、格栅应变、墙背土压力和锚杆应变的规律,研究了有限填土加筋土-框锚组合体系的力学性能,对该组合体系协同作用进行了分析。试验研究结果表明:Ⅰ级和Ⅱ级墙水平位移变形曲线均呈“)”形分布,位移最大值位于每级墙距墙顶约1/3墙高处,锚杆预应力使墙面水平位移达到原变形位移的67%,框锚与有限填土加筋土具有较好的协同效应。随着试验荷载的增加,Ⅰ级墙底部筋材应变随荷载变化增幅较小,对荷载变化不敏感,Ⅰ级墙中上部应变筋材随荷载变化增幅较大,对荷载变化敏感,有限填土加筋土与挖方区域交界面处筋材应变增幅较小;Ⅱ级墙的筋材应变均呈峰形分布,有限填土加筋土与挖方区域交界面处最先发生破坏。锚杆预应力施加可减少各层筋材应变,模型框架梁后土压力和有限填土加筋土后土压力有所增加,锚杆预应力能改变体系内的土压力分布形式,锚杆预应力能较好调节有限填土加筋土和框锚协同工作性能。
Aiming at the problem of limited apace,high-volume backfill filling,horizontal deformation in the treatment and reinforcement of high slope sliding in loess region,a composite system of reinforced soil with limited backfill and anchor frame beam was proposed.Taking a high-steep slope in Tongchuan,Shaanxi Province as the case,the physical model test of the synergy of the composite system was carried out for the first time,the horizontal displacement of the panel,the strain of the grid,the backfill soil pressure,and the strain of the anchor rod were discussed.The mechanical properties of the reinforced soil-frame anchor combination system were analyzed.Results show that the horizontal displacement and deformation curves of GradeⅠand GradeⅡwalls are“)”-shaped,and the maximum displacement is about 1/3 of the height of the wall from the top of the wall.The horizontal displacement of the surface reaches 67%of the original deformation displacement value,and the frame anchor has a good synergistic effect with the limited filling and reinforced soil.With the increase of the test load,the strain of the steel bar at the bottom of the GradeⅠwall increases less with the load,and is not sensitive to the change of the load.The strain increase of the reinforcement at the interface between the reinforced soil and the excavation area is small,the strains of the reinforcements of the GradeⅡwall are distributed in a peak shape,and the interface between the reinforced soil and the excavation area with limited filling is the first place to fail.The application of anchor prestress can reduce the strain in each layer of reinforcement,which increases the earth pressure behind the model frame beam and after the finite fill and reinforced soil.The anchor prestress changes the form of earth pressure distribution in the system.Prestress can better regulate the cooperative working performance of reinforced soil with limited backfill and anchor frame beam.
作者
何江飞
姚磊华
HE Jiang-fei;YAO Lei-hua(School of Engineering and Technology,China University of Geosciences(Beijing),Beijing 100083,China;Shaanxi Institute of Engineering Prospecting,Xi’an 710068,China)
出处
《科学技术与工程》
北大核心
2020年第34期14185-14192,共8页
Science Technology and Engineering
基金
中国地质调查局地质调查项目(12120114056901)。
关键词
有限填土
加筋土
锚杆
框架梁
协同作用
limited backfill
reinforced soil
anchor
frame beam
synergistic action
