哈姆山堰塞湖安全评价与综合治理研究

发布时间：2019-04-01 06:47

【摘要】：汶川“5.12”大地震不仅在地震影响区内产生大量的崩塌、滑坡地质灾害,而且在整个核心区内形成了多处堰塞湖,库区内边坡变形破坏有不同程度的增加,尤其在哈姆山段变形破坏强烈,山体滑坡对哈姆湖堰塞湖造成了一定损坏,一旦堰体溃决,湖水快速下泄,将直接威胁阿坝藏族羌族自治州群众的生命安全,危险性极大。因此亟需对哈姆山堰塞湖进行安全评估工作,并对其进行治理。本文在哈姆山堰塞湖坝址处多年平均径流深、设计洪水、分期洪水与溃坝洪水等计算成果的基础上,分析了哈姆山堰塞湖溃坝风险。并结合哈姆山堰塞坝坝基、坝肩地质条件,对哈姆山堰塞坝及坝基、坝肩条件做了安全评价,得到如下结论:沿河槽陡坡存在绕渗稳定问题;砂砾卵石与基岩接触界面处可能存在不均匀沉陷现象;左岸坝肩总体稳定,右岸坝肩为右岸崩塌堆积体,但是两岸坝肩存在绕渗问题。本文分别采用经验公式解析法和平面二维有限元数值分析法对堰塞坝坝体进行了渗流稳定分析计算,计算结果表明堰塞坝上下游渗透稳定满足规范要求,沿堰塞坝向河槽绕渗渗透稳定计算结果不满足规范要求,需要进行防渗处理。同时通过对高边坡进行复核计算,表明堰塞坝右岸高边坡P1破碎带范围边坡不稳定,左岸高边坡H01潜在崩塌体不稳定,且H02潜在滑移体不稳定,需要进行加固处理。最后本文根据哈姆山堰塞湖安全评价结果,针对哈姆山堰塞湖存在的问题,提出了综合治理措施,通过方案比选,采用钢筋石笼对堰塞体右岸主河槽进行防洪护砌,右岸采用浆砌石挡墙,达到堰塞坝泄流槽治理的目的。右岸松散堆积体处理采用挡土墙结合坡顶开挖加固方案,防止滑坡体完全堵塞泄槽。本文为我国堰塞湖安全评估与治理的实际案例,对其他类似工程的建设有一定的参考价值,同时进一步完善了堰塞湖安全评估与治理理论及方法,具有一定的学术价值与工程价值。
[Abstract]:The Wenchuan "5.12" earthquake not only produced a large number of collapses and landslides in the earthquake-affected areas, but also formed a number of dammed lakes in the whole core area, and the slope deformation and destruction in the reservoir area increased in varying degrees. Especially in the Hamshan section, the deformation and destruction is strong, and the landslide has caused certain damage to the Hamhu barrier lake. Once the Weir body collapses, the lake water will drain rapidly, which will directly threaten the life safety of the masses in the Aba Tibetan and Qiang Autonomous Prefecture, and it will be very dangerous. Therefore, it is urgent to evaluate the safety of Hamshan dammed lake and to control it. Based on the calculation results of average runoff depth, design flood, phased flood and dam break flood at the dam site of Hamshan dammed lake, the risk of dam break in Hamshan dammed lake is analyzed in this paper. Combined with the geological conditions of the dam foundation and abutment of Hamshan Weir, the safety evaluation of Hamshan dam, dam foundation and abutment conditions is made, and the following conclusions are drawn: there is a problem of seepage stability along the steep slope of the river channel; There may be uneven subsidence at the contact interface between gravel pebbles and bedrock, and the left bank abutment is generally stable, and the right bank abutment is a right bank collapse and accumulation body, but the cross-strait dam abutment has the problem of circumfluence. In this paper, the seepage stability of dam body is analyzed and calculated by empirical formula analysis method and plane two-dimensional finite element numerical analysis method, respectively. The results show that the seepage stability of upper and lower reaches of the dam meets the requirements of the code. The results of seepage stability calculation along the dammed dam into the channel do not meet the requirements of the code and need to be treated with anti-seepage. At the same time, through the calculation of the high slope, it is shown that the slope of the right bank of the dam is unstable in the range of the high slope P1, the potential collapse of the high slope H01 on the left bank is unstable, and the potential sliding body of H02 is unstable, so it is necessary to strengthen the slope. Finally, according to the result of safety evaluation of Hamshan dammed lake and aiming at the problems existing in Hamshan dammed lake, this paper puts forward the comprehensive control measures. Through the scheme comparison and selection, the reinforced stone cage is used to protect the main channel of the right bank of the dammed body for flood control and protection. On the right bank, mortar masonry retaining wall is used to control the discharge channel of dammed dam. In the treatment of loose accumulation on the right bank, retaining wall combined with excavation and reinforcement on the top of the slope is adopted to prevent the landslide body from completely blocking the drain channel. This paper is a practical case of safety assessment and management of dammed lake in our country, and has certain reference value to other similar projects construction. At the same time, the theory and method of safety assessment and management of dammed lake have been further perfected. It has certain academic value and engineering value.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV882.9

【相似文献】