基于振动台试验的抗滑桩加固斜坡桥基研究  

Study of bridge foundation on slope reinforced by anti-slide piles on shaking table

作　　者：雷达[1,2] 蒋关鲁[1,2] 孙圣杰[1,2] 戚志慧[1,2] 李安洪 LEI Da;JIANG Guan-lu;SUN Sheng-jie;QI Zhi-hui;LI An-hong(School of Civil Engineering,Southwest Jiaotong University,Chengdu,Sichuan 610031,China;Key Laboratory of High-Speed Railway Engineering, Ministry of Education,Southwest Jiaotong University,Chengdu,Sichuan 610031,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu,Sichuan 610031,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]西南交通大学高速铁路线路工程教育部重点实验室,四川成都610031 [3]中铁二院工程集团有限责任公司,四川成都610031

出　　处：《岩土力学》2019年第1期127-134,146,共9页Rock and Soil Mechanics

基　　金：铁道部科技研究开发计划重大课题(No.Z2012-061)~~

摘　　要：基于工程实践中研究斜坡桥基抗震加固的需要,设计并完成前后排抗滑桩加固滑坡桥基的振动台模型试验。通过加载不同频率、加速度峰值的正弦波,分析振动时桥墩基桩、抗滑桩的受力变形规律,探讨滑坡破坏发展过程和动力响应特性。试验结果显示,前后排抗滑桩均应与桥基保持合理距离,有利于桥墩基础的受力变形;受桥梁上部结构的动力影响,桥墩基桩应变沿桩深衰减,衰减速度与土体抗力相关;当后排抗滑桩开裂后,桩身应变骤降,桩后土压力出现卸荷效应,但抗滑桩仍有潜在的承载能力,同时滑坡从稳定性最差的区域开始破坏,逐渐产生频段耦合效应,在后排抗滑桩达到承载极限前,频段耦合效应显著,达到承载极限后,卸荷效应显著。As the research demands develop in the seismic reinforcement of bridge foundation on slope in engineering practice, a shaking table model test of bridge foundation on a slope reinforced by the front and back row anti-slide piles is introduced, in which the dynamic loading is applied in form of sine waves with different frequencies and peak accelerations. This study emphasis on the analysis of mechanical responses of the bridge foundation and anti-slide piles, and the developing process of landslide and dynamic response performance. Results show that the front and back row anti-slide piles should keep a proper distance to the bridge foundation, so that the mechanical responses of bridge pile foundation are more reasonable. As the dynamic load of upper structure affect bridge foundation greatly, the strain decreases along pile depth and the strain attenuation is related with soil resistance. When the back row anti-slide piles are cracking, the pile strain decreases significantly and the unloading effect appear in soil pressure behind piles. However, there is potential bearing capacity on pile strength. The landslide failure starts in the section dangerous in stability. The frequency-band coupling effect produce gradually before the back row anti-slide piles reaching the limit loading in vibration, and then the unloading effect take over after the limit loading state.

关 键 词：抗滑桩 桥梁基础 振动台模型试验 卸荷效应 频段耦合效应 

分 类 号：TU473[建筑科学—结构工程]