为了探求合理的隧道锚抗拔安全系数评估方法，依托西南某跨越金沙江的大桥隧道锚工程，分别采用应力积分法、塑性屈服区体积-荷载曲线和位移-荷载曲线求解隧道锚的抗拔安全系数，并将3种方法的计算结果与规范法的结果加以对比.结果表明：规范法忽略了岩体对锚碇的夹持作用，故其计算所得抗拔安全系数相对最小，仅为 2.60；应力积分法取用设计荷载工况对应的应力场，夹持效果不明显，因而计算结果接近于规范法，采用应力积分法所得锚碇-围岩界面及围岩内破坏面的抗拔安全系数分别为 2.64 和 2.88；采用塑性屈服区体积-荷载曲线及位移-荷载曲线时，容许荷载作用下的锚碇-岩体能够充分接触，夹持效果显著，故所得抗拔安全系数最大，其值均为 6.50；通过极限摩阻力来反推锚碇-岩体界面夹持力，可得考虑夹持效应的隧道锚的抗拔安全系数.
In order to study the reasonable assessment method of the safety coefficient of tunnel-type anchorage, three different methods—stress integration method, displacement load curve method and plastic area-load curve method are used to solve the uplift stability coefficient of tunnel-type anchorage. And the specification value is also given to make a comparison with the values obtained from the three methods. Results show that the stability coefficient given by specification method is comparatively small because this method neglects the clamping effect of rock to anchor. The value of safety coefficient calculated by this method is only 2.60. And stress integration method takes the stress field corresponding to the design load as the calculation stress, in which case the clamping effect is out of action. Therefore, the coefficients calculated by this method are close to the value of specification method. The safety factor calculated by this method is 2.64 when the failure mode of tunnel-type anchorage is interface failure. And the value is 2.88 while the failure mode is rock failure. In addition, the safety coefficient obtained from both plastic area-load curve and displacement load curve methods are 6.50, the biggest value of all methods. Because the rock and anchor contact each other closely and the clamping effect works effectively under the maximum permitted load. Last but not least, the uplift safety coefficient of tunnel-type anchorage with the clamping effect into consideration can be calculated when the bearing force of interface can be calculated by the ultimate lateral resistance.
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