标题:
红椿沟泥石流治理工程防灾效果数值模拟研究The Study on Numerical Simulation of Debris Flow Disaster Prevention Engineering Effect in Hongchun Gully, Sichuan Province
作者:
杨国辉, 孙书勤
关键字:
红椿沟, 泥石流, 防灾效果, 数值模拟Hongchun Gully, Debris Flow, Disaster Prevention Effect, Numerical Simulation
期刊名称:
《Advances in Geosciences》, Vol.6 No.3, 2016-06-08
摘要:
本文研究区为红椿沟流域，位于2008年5.12汶川大地震震中映秀镇的东北侧，全流域面积约为5.35 km2，红椿沟为岷江左岸一级支沟，在形态特征上呈现长条状扇形特征，研究区海拔最高点为沟源处望乡石高程为2169.2 m，最低点为沟口，高程881 m，全流域的相对高程差达到1288.2 m。流域主沟长约3.6 km，纵坡率约为357.8‰。研究中发现，红椿沟治理工程竣工后，发生了两次设计工况下的泥石流和一次超标暴雨工况下的泥石流，为合理判断治理工程数值模拟的防灾效果，将模拟结果与工程实际运行效果监测数据相比较，故本文在数值模拟时，选择具有代表性的2种不同频率的重现周期(p = 2%, p = 1%)进行泥石流暴发模拟，同时根据不同区段的监测数据，本文在模拟过程中通过合理设置集水点位置，将治理工程分段进行了防治效果模拟。红椿沟泥石流治理工程在设计工况下(p = 2%)的数值模拟中防灾效果显著，在超标暴雨工况下(p = 1%)的数值模拟中抗灾效果显著。
The study area Hongchun basin is located in the northeast side of Yingxiu Town, which is the 2008.5.12 Wenchuan earthquake epicenter. It is also located on the left bank of the Minjiang River. The ditch and valley pattern is approximate a sector and its area is 5.35 km2. The highest point is located in Xin Dian Zi Gou’s source; the elevation is 2162.2 m; Mizoguchi and Minjiang River in-tersection height is 881 m; relative elevation is 1288.2 m; channel longitudinal is 3.6 km; average longitudinal gradient of gully is 357.8 per thousand. It was found in the study that after the Hong-chun gully disaster prevention project completed, it has broken twice debris flow in the design condition and once debris flow exceeding the design condition. In order to reasonably judge the effect of the project, we compared the simulation results with the actual operation results of the project. So in the numerical simulation of this article, we selected 2 representative recurrence pe-riods of frequencies (p = 2%, p = 1%) to simulate. At the same time, according to the monitoring data of different sections and by setting up reasonable water gathering point positions in the si-mulation process, the disaster prevention project is divided into several sections for numerical simulation in this article. The numerical simulation results show that, in the design condition (p = 2%), the Hongchun gully disaster prevention engineering effect is remarkable, and over the design condition (p = 1%) the effect is also good.