【作者】 程吉建；

【导师】 龙腾锐；

【作者基本信息】 重庆大学 ， 环境工程， 2004， 硕士

【摘要】 三峡水库蓄水后,长江流域的水流速度将变慢,稀释、扩散能力下降,库区水污染防治问题已迫在眉睫,兴建城市污水处理工程刻不容缓。排水管网作为城市污水处理工程的重要组成部分,在促进三峡库区经济建设发展、保护库区环境免受污染、保障库区人民健康方面起着至关重要的作用。重庆三峡库区绝大多数城市市政设施建设大大滞后,远远不能满足污染防治的需要。加之地形复杂,绝大多数市县属于山地城市,排水管网规划建设存在很大困难。本论文在对国内外城镇排水管网的设计资料的大量分析的基础上,结合重庆三峡库区的实际特征和作者的工程经验,对三峡库区排水体制选择、管网设计特点和难点进行了分析,并提出了建议。在排水体制的选择中,对于旧城改造,通常情况下,新区按分流制规划建设排水管网,老城区根据目前三峡库区城镇的地理条件、经济实力、居民素质等实际因素推荐采用截流式合流制排水系统,在旧城改造中,逐步将合流制排水系统改造成一个分流不完全的分流制排水系统。对于新建城区,由于三峡库区的特殊性,必须采用分流制排水体制,污水分区收集后经污水处理厂处理达标排放,雨水经雨水系统收集后靠重力流就近排入水体。实际设计时,可以结合当地特点选择不同的排水体制或者两种排水体制并存。库区污水管网系统设计时,须考虑山地城市地质地貌特点,应采用与地形相适应的管道敷设方式,以达到近远结合、布局合理、投资少、建设快的目的。同时,对合理预测污水流量,确定污水管管径和埋设深度进行了一系列分析。并且阐述了淤积污泥的组成,以及泥沙颗粒大小的与流速的关系,确定合适的最小流速。对库区雨水管网的设计,本文提出了较为准确的重庆暴雨强度公式,并且对主城区、待开发区和半开发区的径流系数的确定提出了一些可行性建议。由于重庆很多地方存在不良地质,本文也分析了排水管涵布置与不良地段的预防、处理。本论文探讨的适合重庆排水管网设计与施工的措施,对今后重庆小城镇排水管网的建设具有参考意义。更多还原

【Abstract】 After Three Gorges Reservoir sluices, water velocity of Yangtse River will slow down, dilution and diffusion ability will decline, too. It is urgent to prevent water pollution and construct municipal wastewater treatment project. As an important part of this, the construction of drainage pipe network system in Three Gorges Reservoir area is taking an important role in promoting economic development, protecting water pollution and safeguarding public health.Majority of cities and towns in Chongqing are so weak in municipal facilities that can’t meet the need of water pollution and cure. In addition, the complexity of land form gives the programming and construction of drainage pipelines great difficulties. This study is based on a great deal of domestic and foreign design materials, combines the practical character of Chongqing Three Gorges Reservoir and writer’s work experience of many years, analyzes the choice of drainage system, the characteristic and difficult point of pipeline design and gives some suggestions.When choosing the drainage system, there are two situations. One is the alteration of an old town. Separate systems should be used in new zones, and intercepted combined systems are recommended to be used in old zones, because of the geography, the current economic strength, citizen quality and other practical factors. Faulty combined systems should be changed to incomplete separate systems gradually. The other situation is that separate systems should be introduced in a brand new town. When designing, we can use one of the two systems or both of them at the same time according to local characteristics. When designing sewage pipelines, in the purpose of near-remote future combination, appropriate layout, low investment and rapid construction, we should use different lay ways to adapt to different land forms, in terms of the traits of mountainous regions. The paper also discuss how to anticipate sewage rate, how to decide pipe diameter and the depth of burying. Simultaneously, it also discusses the composition of mud accumulation, the relationship between the size of sand grain and velocity and how to decide appropriate minimum velocity.When designing rainwater pipelines, the paper puts forward relative accurate storm intensity formula and give some feasible advice about the decision of runoff coefficient. <WP=9>The layout of pipe culverts and the prevention and treatment of bad land sectors are also discussed. The measures about drainage pipe network design in Chongqing which are discussed in this paper may be consulted in the construction of drainage pipe network in Chongqing Three Gorges Reservoir in the future.更多还原