不同应力场软弱围岩公路连拱隧道中墙受力特征

Stress characteristics of middle wall in soft-wreak surrounding rocks highway multiple-arch tunnel under different stress field

为了更全面了解不同应力场软弱围岩公路连拱隧道中墙的受力特征,选择曲中墙连拱隧道结构形式,建立有效的有限元模型,采用不同加载方式,模拟不同应力场,对软弱围岩公路连拱隧道中墙受力特征进行研究,详细分析了应力场对中墙结构受力的影响,并运用模型试验结果对数值计算结果进行了验证。结果表明:不同的应力场中,中墙顶部,侧压力系数越小,施工中偏压越明显;中墙中部和底部,侧压力系数越大,施工中偏压越明显;侧压力系数越小,中墙竖向应力量值越大。

In order to understand the mechanical characteristics of middle wall in highway multiple-arch tunnel under different stress field more fully,this paper established the effective finite element model based on the structure of curved middle-wall multiple-arch tunnel,used different loading to simulate different stress field,reached on the middle wall mechanical characteristics of highway multiple-arch tunnel in soft rock in different stress field,analyzed the impact of the supporting structure by force on stress field,contrasted the results of model test and simulation analysis.The results show that： the bias in construction become more significantly with the smaller coefficient of lateral pressure in the top of the middle wall;the bias in construction become more significantly with the larger coefficient of lateral pressure in the middle and bottom of the middle wall;the vertical become larger with the smaller coefficient of lateral stress.1 tab,7 figs,9 refs.