四川阎王曲二支沟泥石流危险性评价

Hazard Assessment of Debris Flow in the Second Branch Ditch of Yanwangqu

阎王曲二支沟位于鹧鸪山隧道出口上游约380m处,为一老泥石流沟。隧道出口位于泥石流堆积体中,泥石流的暴发将对隧道出口及引道带来直接危害。因此,预测及评价该泥石流沟的发展趋势及危险性对合理制定泥石流防治措施,确保隧道的安全运行具有重要意义。根据泥石流发育特征及形成条件的地质地貌演化分析,该沟仍具有再次暴发泥石流的较大可能性,危险性评价表明,该沟泥石流的危险度为0.50,属中度危险。根据泥石流的活动特征,提出了以疏导为主的防治方案,并对隧道口直接受泥石流威胁的一侧采用一定的拦挡工程等措施。

The second branch ditch of Yanwangqu is an old debris flow and the tunnel exportation of Zhegu mountain is located its downriver about 380 m. The debris flow will endanger the export because it lies in the accumulation of debris flow. Its hazard assessment is the necessary prerequisite for the control schemes of debris flow and the security function of the tunnel. In terms of the characteristic of debris flow and the physiognomy analysis, it is highly possible that this ditch still explodes once more. The preparatory assessment of hazard indicates that the second branch ditch has hazard value of 0. 50, belonging to moderate hazardousness. According to the above, we should carry out the leading measure and construct the dam to restrain the debris flow at the side of tunnel exportation.