人工弃渣诱发泥石流的动力学研究--以三峡库区巴东县黄家大沟为例

由于地形条件限制，在三峡库区大规模的城镇迁建过程中产生了大量的人工弃渣或建筑垃圾，随着人工弃渣量的不断增加，人为泥石流灾害将成为迁建城镇不可忽视的环境工程地质问题。三峡库区巴东县新城区黄家大沟中的人工弃渣主要是道路、场地施工和开采建筑材料所产生的固体松散堆积物和少量生活垃圾，主要分布在新城区沿江路和中环路两条主干道附近。本文在实地调查的基础上，阐述了沟谷中人工弃渣的物质组成和堆积特征，认为不同部位的弃渣堆积体在暴雨作用下的变形特征和诱发泥石流的可能性有所差异，启动机理大致可以分为中环路下方的沟槽拖曳启动型和沿江路北侧堆积体的强度衰减启动型。结合巴东县2003年3月31日至4月1日强降雨过程，着重分析了沟槽拖曳型泥石流的动力学特征，并对黄家大沟人工弃渣堆积体的活动性和诱发泥石流的可能性进行了初步预测。

Dynamics of Debris Flow Caused by Human Waste-Dump: A Case Study of the Huangjia Valley in Badong County of the Three Gorges Region

Due to the topographic conditions, plenty of human waste-dump is produced in the reservoir area of the Three Gorges region during the reconstruction of new cities, which makes the human-caused debris flow one of the serious environmental geological problems. The human waste-dump accumulated in the Huangjia Valley of Badong County in the Three Gorges region is composed of solid materials formed during the road and site construction and the development of construction materials and a small amount of house refuse. Based on field investigation, this paper describes the composition and piling characteristics of the human waste-dump. It is realized that the deformation characteristics and possibilities of debris flows are somewhat different in different places under the effect of rainstorm. The initiation mechanisms of debris flow can be divided into the type of groove transportation by traction and that of slope strength attenuation. Taking the heavy raining process from March 31 to April 1, 2003, into account, this paper has emphatically analyzed the dynamic characteristics of debris flow near the Zhong-huan-lu road, and predicted the future activity of the human waste-dump and the possibility of debris flow in Huangjia Valley.