南水北调中线膨胀土（岩）渠段问题及成因分析

马慧敏 何向东 张帅 刘吉永

摘 要：对南水北调中线工程膨胀土（岩）渠段常见实体问题及成因进行了总结与分析，指出：膨胀土（岩）渠段实体问题一般可分为过水断面的原边坡、处理层、防护层实体问题以及非过水断面的原边坡、处理层、防护层实体问题。总干渠过水断面的原边坡或者处理层破坏会影响渠道正常运行，后果严重，应避免非自然原因引起的此类破坏。非过水断面的原边坡或者处理层破坏一般不会影响渠道正常运行，但应排除影响到过水断面的深层边坡滑动以及大方量滑坡破坏影响到渠道正常运行。对于防护层出现损坏的应综合分析是否与边坡深层破坏有关，并根据研究结果提出相应的研判标准。

关键词：膨胀土（岩）边坡;实体问题;南水北调中线工程

中图分类号：TV91 文献标志码：A

doi：10.3969/j.issn.1000-1379.2020.02.027

Abstract：This paper summarized and analyzed the common physical issues and causes of the drainage section of expansive soil（rock） in the middle line of South-to-North Water Diversion Project. It is pointed out that the physical issues of expanded geotechnical channel can be generally divided into the original slope， treatment layer and physical issues of protection layer of flow section and original slope， treatment layer and physical issues of protection layer of non-flow section. The destruction of the original slope or the filling layer of the main canal cross section will affect the normal operation of the channel， and the consequences are serious. Such damage caused by unnatural causes should be avoided. The failure of the original slope or filling layer of the non-flow section generally does not affect the normal operation of the channel， but it should be ruled out that the deep slope sliding that affects the flow section and the extensive landslide damage affects the normal operation of the channel. According to the relevant monitoring data， it is necessary to comprehensively analyze whether the damage to the protective layer is related to the deep slope damage， such as whether the accumulated displacement of the slope exceeds the alert value， whether the monitoring data has mutated， etc.， and according to the research results， the corresponding evaluation standards are put forward.

Key words： expansive soil slope;substantive issues; Middle Route Project of South to North Water Transfer

南水北調中线工程自2003年12月开工建设，至2014年12月正式通水，历时11 a。工程建设期间，南水北调工程各项目法人、设计、施工、建设管理等工程参建单位，以及相关科研院所、高等院校，先后开展了包括南水北调工程“十一五”国家科技支撑计划重大项目“膨胀土地段渠道破坏机理及处理技术研究”以及“十二五”国家科技支撑计划项目“南水北调中线工程膨胀土和高填方渠道建设关键技术研究与示范”等多项科技项目的研究，取得了丰硕的成果，为工程顺利建设奠定了技术基础。目前，南水北调中线工程已全面进入运行期，日常管理维护过程中发现工程还存在一些诸如膨胀土（岩）渠段渠坡浅层破坏，渠道衬砌面板局部隆起、沉陷、裂缝，坡顶截流沟破坏，坡面排水沟裂缝、变形等情况。……