多级边坡格构式锚杆支护结构的抗震分析理论与设计方法

Lattice anchoring structure is one of the most commonly used supporting structures for multistage slope. Due to a lack of relevant research achievements, the seismic analysis theory for the lattice anchoring structure supporting multistage slope has lagged behind the engineering practice. Based on engineering entity, the seismic ground motions with wide frequency domain, high strength and multidimensionality are applied by means of shaking table test and three dimensional numerical simulation to analyze the seismic response characteristics and deformation patterns of the lattice anchoring structure supporting multistage slope. The dynamic mechanism and the potential failure mode of the lattice anchoring structure supporting multistage slope are revealed. Based on the energy consumption analysis method, the failure mechanisms of the lattice anchoring structure supporting multistage slope are established, and the strength formulas for the seismic stability, the axial anchor force and the yield acceleration of such structure system are deduced. The motion equation of slope, lattice beam and anchor system is established, and the seismic permanent deformation formula is derived based on the sliding block theory. With a reference to the shaking table test and numerical simulation results, the seismic analysis formulas for the lattice anchoring structure supporting multistage slope is revised and improved, and the seismic design method for such structure system is proposed based on the strength and deformation control. A visual program is developed on the seismic analysis of the lattice anchoring structure supporting multistage slope with an inclusion of the shaking table test and numerical simulation data. This project will provide an effective and practical seismic analysis theory and method for the lattice anchoring structure supporting multistage slope, and the research results are expected to be included in a professional seismic code.

格构式锚杆结构是多级边坡最常用的支护形式之一，由于缺乏相关研究成果，多级边坡格构式锚杆支护结构的抗震分析理论已落后于工程实践。项目依托工程实体，通过振动台试验和三维数值仿真实现地震动的宽频域、高强度和多维度输入，分析多级边坡格构式锚杆支护结构的地震响应特性和变形模式，揭示其动力学作用机理和潜在破坏模式；基于能耗分析法建立多级边坡格构式锚杆支护结构的运动破坏机构，推导结构体系的地震稳定性、锚杆轴力、屈服加速度等强度公式；建立边坡、格构梁和锚杆体系的运动方程，基于滑块理论推导地震永久变形公式；结合振动台试验和数值仿真结果，改进和完善多级边坡格构式锚杆支护结构的抗震计算公式，提出基于强度和变形控制的结构体系抗震设计方法；开发多级边坡格构式锚杆支护结构抗震分析的可视化程序，并嵌入试验和数值仿真数据。项目将为多级边坡格构式锚杆支护结构推荐有效、实用的抗震分析理论与方法，研究成果可望纳入行业抗震规范。

我国地震活动频繁而又强烈，是世界上大陆地震最活跃、灾害最严重的国家之一。近些年来强震造成了大量的岩土构筑物破坏，给抗震设防技术带来了新的课题。格构式框架锚杆结构是边坡最常用的支护形式之一，但其抗震分析方法仍停留在半经验半理论阶段。项目以多级边坡格构式锚杆支护结构为研究对象，采用振动台试验、数值模拟、理论分析、程序开发等手段，分析多级边坡格构式锚杆支护结构的抗震特性，推导支护结构的抗震计算公式。主要工作有：.（1）多级边坡格构式锚杆支护结构地震响应振动台试验。通过振动台试验输入不同地震动激励，测试不同工况下支护结构的加速度响应、动应力响应、动位移响应、残余土压力、锚杆轴力响应等，借助高速摄像三维图像分析技术记录试验过程，对支护结构的地震响应特性进行分析。.（2）多级边坡格构式锚杆支护结构地震响应数值模拟。建立支护结构的三维数值分析模型，分析不同地震波激励下支护结构关键节点和单元的加速度响应、速度响应、动应力响应、动位移响应、锚杆轴力响应等。分析地震动频率、幅值对支护结构抗震性能的影响。 .（3）多级边坡格构式锚杆支护结构的抗震分析理论。基于极限分析上限理论，建立支护结构地震稳定系数的目标函数，通过目标优化方法搜索支护结构最危险滑裂面。改变目标函数形式，推导屈服加速度、锚杆轴力的计算公式，基于滑块理论求解支护结构永久变形。.（4）多级边坡格构式锚杆支护结构的抗震分析程序。基于MATLAB平台设计多目标优化算法，完成支护结构的地震稳定系数、锚杆轴力的计算和分析。设计支护结构抗震分析的交互式可视化界面，完成输入输出功能、输入提示功能等。 .项目以工程需求为出发点，获得了多级边坡格构式锚杆支护结构地震响应翔实的研究成果，提出了抗震计算方法。研究成果可为多级边坡格构式锚杆支护结构抗震设计提供科学依据，具有显著的理论意义和工程应用价值。