鉴于对公路隧道抗震计算的简化算法迄今研究尚少，提出了一种适用于公路隧道地震响应计算的拟静力法。以Ⅳ级围岩中的双车道公路隧道为例，通过将衬砌结构视为弹性地基上的框架结构，将结构承受的水平地震力简化为作用在结构单元结点上的等效水平集中力，侧向地基弹性抗力假设为按倒三角形分布，墙底为零，拱顶为最大值，其值按与水平等效地震力平衡的原则确定。通过比选确定水平地震作用修正系数 η 的取值，即可由结构静力分析得到与结构动力响应分布图形相似、最大值十分接近的等效弯矩图，其相应的最大轴力值和最大剪力值，可通过由结构静力分析得到的内力图结果分别乘以轴力、剪力调整系数获得。提出的方法可供工程设计及公路隧道地震响应进一步研究参考。

Rare researches were focused on the simplified method of aseismic calculation for highway tunnels. A quasi-static calculation of the seismic response of highway tunnel is proposed. In this method, the tunnel lining structure is regarded as frame structure on elastic foundation, and the horizontal seismic force on the structure is simplified as equivalent horizontal concentrated force on element nodes of the structure. The lateral elastic resistance is assumed to be distributed in an inverted triangle, which is zero at the bottom of the wall and reaches the maximum at the vault. The value of lateral elastic resistance should be in balance with horizontal equivalent seismic force. A double-lane highway tunnel with rock of grade Ⅳ is taken as a case study. Through comparison and selection, the value of correction coefficient  η  of the horizontal seismic action is determined. Hence, through static structural analysis, the equivalent bending moment diagram is obtained, which is similar to the distribution graph of dynamic analysis, with the maximum values close to each other. The corresponding maximum axial force and maximum shear force can be obtained through respectively multiplying the adjustment coefficient of axial force and shear force by the internal force resulted from the static structural analysis. The method could be taken as a reference for engineering design and further research.