考虑透水夹层作用下富水山区隧道涌水量预测

为了实现对隧道侧面存在透水夹层时隧道涌水量的精准预测,以“圆岛模型”和映射原理为理论基础,推导了透水夹层作用下隧道涌水量预测公式。通过改变围岩渗透系数、透水夹层厚度、隧道与透水夹层中心距等因素,分析了各个因素对隧道涌水量的影响规律。结果表明：理论计算值与实际勘测值基本吻合,误差为10.4%;随着围岩渗透系数或者透水夹层厚度的增大,隧道涌水量值呈线性增大,趋于稳定时增幅分别约为30%和20%;随着隧道与透水夹层中心距的增大,隧道涌水量值呈非线性下降,最大降幅为27.7%,稳定时降幅约为8%;若同时改变围岩渗透系数、透水夹层厚度、隧道与透水夹层中心距中的任意两种,通过分析可知,围岩渗透系数对隧道涌水量的影响最明显,透水夹层厚度次之,隧道与透水夹层中心距最弱。

The prediction of water inflow of water-rich mountain tunnel under permeable interlayer is considered

In order to realize accurate prediction of tunnel water inflow when there is permeable interlayer on the side of the tunnel, based on "round island model" and mapping principle, to deduce the prediction formula of tunnel water inflow under special geological environment. By changing the permeability coefficient of surrounding rock, the thickness of permeable interlayer and the distance between the center of tunnel and permeable interlayer, the influence law of each factor on the tunnel water inflow was analyzed. The results show: The theoretical calculated value is basically consistent with the actual survey value, and the error is 10.4%. With the increase of the permeability coefficient of surrounding rock or the thickness of permeable interlayer, the water inflow value of the tunnel increases linearly, with the increase of about 30% and 20% respectively when it tends to be stable. With the increase of the distance between the tunnel and the permeable interlayer, the water inflow value of the tunnel decreased nonlinearly, the maximum decrease was 27.7%, and the decrease was about 8% when it was stable. If two of the permeability coefficient of surrounding rock, the thickness of permeable interlayer, and the center distance between tunnel and permeable interlayer are changed simultaneously, the analysis show that the permeability coefficient of surrounding rock has the most obvious influence on the water inflow of the tunnel, followed by the thickness of permeable interlayer, and the distance between the center of tunnel and permeable interlayer is the weakest.