首页|地震作用下桩板墙-锚索组合支护基覆型边坡的动力响应特性

地震作用下桩板墙-锚索组合支护基覆型边坡的动力响应特性

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地震作用下,惯性力方向对组合结构、土体、岩体的平衡状态影响显著.为深入理解桩板墙组合支护结构-基覆型边坡相互作用特性,以西南地区一隧道进口端基覆型高陡边坡为原型,开展一组简谐波加载下组合结构加固边坡的大型振动台模型试验,考虑惯性力方向对桩-土、格构锚索-坡体时程特性展开分析.结果表明:(1)惯性力作用下格构锚索-土体相互作用与桩-土相互作用表现出近似的时程-致性规律,但坡面加固结构惯性力峰值沿高程存在的相位差不可忽视.(2)结构与边坡土体的相互作用大小取决于相对惯性运动,桩-基岩相互作用由悬臂段变形状态决定.(3)惯性力达到临空面峰值,动土压力达到峰值,桩-土位移差达到正向峰值,桩身呈现外倾的主动破坏状态,锚固段前侧受力因外倾而挤压增大,因而悬臂段采用库仑主动土压力进行设计需结合桩土状态进行修正.(4)简谐波作用下,坡体惯性力及变形是组合支挡结构沿高程受力分布特性的关键因素,组合结构设计时需重点关注坡脚应力集中区及坡顶惯性力放大区.本研究可为组合结构抗震加固设计提供理论支撑.
Dynamic response characteristics of bedrock and overburden layer slope supported by a combination of pile-sheet wall-anchor cables under earthquake action
The direction of inertial force under seismic conditions has a significant impact on the equilibrium state of combined structures,soil,and rock masses.To gain a deep understanding of the interaction characteristics between the pile-plate wall combined support structure and the bedrock and overburden layer slope,a series of large-scale shaking table model tests on the slope reinforced by combined structures under sinusoidal wave load were conducted,using a high steep slope at the tunnel portal in the southwestern region as a prototype.The analysis of the time-history characteristics of the pile-soil and the geogrid-anchor cable-slope under the direction of inertial force was considered.The results indicate:(1)Under the action of inertial force,the lattice anchor cable-soil interaction and pile-soil interaction show an approximate time-history consistency law,but the phase difference between the peak value of the inertial force of the slope reinforcement structure along the elevation cannot be ignored.(2)The interaction between the structure and the slope soil depends on the relative inertial motion,and the pile-bedrock interaction is determined by the deformation state of the cantilever section.(3)The inertial force reaches the peak value of the free surface,the dynamic soil pressure reaches the peak value,the pile-soil displacement difference reaches the positive peak value,the pile body shows an active failure state of camber,and the stress on the front side of the anchoring section increases due to camber,so the design using Coulomb active earth pressure should be revised based on the pile-soil conditions.(4)Under sinusoidal wave conditions,the inertial force and deformation of the slope are crucial factors affecting the force distribution characteristics of the combined retaining structure along the elevation.The design of the combined structure needs to focus on the stress concentration area at the foot of the slope and the inertial force amplification area at the top of the slope.This research can provide theoretical support for the seismic reinforcement design of combined structures.

high steep slopepile-plate wallanchorshaking table testinteractiontime-history characteristicsphase

何梓雷、蒋关鲁、冯海洲、潘申鑫、何晓龙、李杰

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西南交通大学土木工程学院,四川成都 610031

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

中铁十八局集团有限公司,天津 300222

高陡边坡 桩板墙 锚索 振动台试验 相互作用 时程特性 相位

国家重点研发计划"政府间国际科技创新合作"重点专项国家自然科学基金资助项目中铁十八局集团科研项目

2022YFE0104600523784632019H010504

2024

岩土力学
中国科学院武汉岩土力学研究所

岩土力学

CSTPCD北大核心
影响因子:1.614
ISSN:1000-7598
年,卷(期):2024.45(7)
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