不同面板型式加筋土挡墙振动响应数值分析

Numerical simulation of the vibration responses of reinforced soil-retaining walls with different facings

摘要:

以刚/柔组合墙面加筋土挡墙的振动台试验结果为基准,建立刚/柔组合式、模块加返包式、模块式和格宾式面板型式加筋土挡墙的FLAC^3D数值模型,研究面板型式对挡墙水平位移、加速度响应及地震土压力分布的影响。结果表明:在静力作用下不同面板型式挡墙的变形模式略有不同;振动作用下,变形大小为组合式＜模块加返包式＜格宾式＜模块式;加筋区内加速度放大系数为组合式＞模块加返包式＞格宾式＞模块式;面板处加速度放大系数均大于加筋区,且面板型式不同,放大规律亦不同;面板型式不同,地震主动土压力非线性分布规律不同;合力作用点位置大多高于M-O方法的H/3,且受加速度幅值影响较小。

Abstract:

Based on the shaking table test results of a reinforced soil-retaining wall with rigid/flexible facings, FLAC^3D numerical models of reinforced soil-retaining walls with rigid/flexible facings, modular facing embedded return package structure, modular facing, and gabion facing were established, and the influence of different facings on the horizontal displacement, acceleration response, and seismic earth pressure distribution of the retaining wall was analyzed. The results show that the deformation modes of the retaining walls with different facings slightly differ under static loading. Under the action of vibration, the magnitude of facing deformation is rigid/flexible facing ＜ modular facing embedded return package structure ＜ gabion facing ＜ modular facing. The acceleration amplification factor in the reinforced zone is rigid/flexible facing ＞ modular facing embedded return package structure ＞ gabion facing ＞ modular facing. The acceleration amplification factor is greater at the facing than in the reinforced zone. The acceleration amplification laws and the nonlinear distribution laws of seismic active earth pressure differ among the facings. The position of the resultant force action point is mostly higher than H/3 of the M-O method, and it is less affected by the acceleration amplitude.