摘要
通过一系列剪切模型试验,研究在不同法向力、预应力和锚固情况下锚索对平滑节理面抗剪性能的影响,利用对比试验将销钉力、预应力和轴力增量3种力的抗剪作用分离出来,着重探讨了在剪切过程中3种力对节理面的抗剪贡献,并分析了锚索模拟体的破坏形式。试验结果表明,预应力锚固明显提高了节理面剪切力-位移曲线初始段的抗剪力和剪切刚度,并使得曲线末段表现出塑性强化的特征;预应力大小对加锚节理面抗剪强度的影响与试验条件、节理面状况和锚固角等有关。试验和理论分析表明,剪切位移开始阶段预应力和销钉作用发挥了主要作用,杆体形成塑性铰后轴力增量则起了重要的作用,锚索的破坏一般发生在节理面附近,属于拉剪复合破坏模式。
By a series of shearing model test, the effect of anchor cable on shear resistance behavior of smooth joints are studied under different normal stresses, prestresses and anchorage conditions. In the model test, shear resistance of dowel force, prestressing force and increment of axial force is separated and the shear contribution of three forces is discussed deeply to joint planes. Contribution to shear strength of joints is discussed due to dowel effect, prestress and increment of axial force in the shear progress, and failure mode of cable simulant is analyzed. Experiment results show that prestressed anchorage improve shear resistance and shear stiffness in initial phase of shear, and prompt joints to show characteristic of plastic-hardening. Experiment results also reveal that effect of prestress on joint shear strength is related with test condition, condition of joint planes and anchorage angle. Experimental and theoretical analyses show that prestress force and dowel effect play a major role in the initial phase of shear displacement and the increment of axial force play an important role after formation of plastic hinge. Cable failure usually occurred in the vicinity of the shear joint due to the combination of shear load and axial load. © 2016, Science Press. All right reserved.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2016年第S2期250-256,共7页
Rock and Soil Mechanics
基金
国家重点基础研究发展计划(973)项目(No.2011CB013502)
国家自然科学基金(No.51409283)~~
关键词
节理面
锚索
剪切试验
预应力
销钉作用
轴力增量
Anchor cables
Anchorages (foundations)
Axial flow
Bolted joints
Cables
Prestressing
Shear strength
Testing
