圆形隧道横断面地震响应简化解析方法的数值验证

NUMERICAL VALIDATION OF SIMPLIFIED ANALYTICAL METHOD FOR SEISMIC RESPONSE OF CIRCULAR TUNNELS

  • 摘要: 简化解析方法因在隧道初步设计中可快速估算隧道结构的地震内力及变形而得到广泛应用,因此对简化解析方法的使用条件及精度进行评价具有重要的工程意义。该文以时域波动有限元方法的数值模拟结果为标准,对Wang、Bobet和Park等3种经典的简化解析方法在不同场地土类别及不同埋深条件下的精度进行了对比验证。结果表明:三种简化解析方法具有相同的轴力预测值,埋深较小时解析解与数值解的误差随着柔度比的增加而逐渐减小,但埋深较大时解析解与数值解的误差随着柔度比的增加先增加后减小;Bobet与Park方法的预测弯矩相同且精度明显优于Wang的方法,其精度随着柔度比的增加而具有逐渐变好的趋势;对于软弱土、中软土、中硬土、坚硬土和岩石等五种类别的场地土,隧道埋深分别大于10 m、5 m、5 m、1 m和1 m时,Bobet与Park方法的轴力与弯矩误差均能小于15%。

     

    Abstract: To provide a quick and easy calculation for the seismic design loads of tunnel lining, the simplified analytical solutions are widely employed in preliminary tunnel design. So it is very important to assess the accuracy and applicability of these analytical solutions. In this study, the time-domain finite element method is adopted to verify the accuracy of four simplified analytical solutions for different types of surrounding soil or rock and different tunnel depths. Through the numerical validation, it can be concluded that: the analytical solutions by Wang, Bobet and Park generate the same thrusts; with the increasing of flexibility ratio, the error deceases for shadow tunnels, and decreases first and then increases for deep tunnels; the Bobet’s and Park’s solutions generate the same bending moments, more accurate than Wang’s solution; the error of Bobet’s and Park’s solutions decreases with the increasing of flexibility ratio; the errors of Bobet’s and Park’s solutions are lower than 15% for tunnel’s internal forces when the tunnel depth is over 10 m, 5 m, 5 m, 1 m and 1 m, respectively for soft soil, medium soft soil, medium hard soil, hard soil or soft rock and hard rock.

     

/

返回文章
返回