西黑岱沟流域坝系相对稳定性分析

 为给小流域坝系工程建设的前期规划工作与科研提供科学依据,根据西黑岱沟流域治理现状及影响坝系稳定有关因子的实测资料,对坝系的相对稳定性进行分析。结果表明,小流域坝系实现相对稳定,其淤地面积虽是最基本条件之一,但不是唯一的条件。衡量坝系是否实现了相对稳定性,必须同时满足以下4个条件:一是每km2的坝控面积范围内应有坝地7.8hm2,坝地面积与坝控面积的比值,即坝系相对稳定系数达到1/12.7;二是坝系运行15a后,每隔3～5a要对坝体进行维修加高,使坝系防洪能力长期保持100年一遇或大于100年一遇的防洪标准;三是在每km2的控制范围内,要有骨干坝0.3座、淤地坝1.0座,坝系的整体布局与结构要达到合理,使暴雨洪水达到均衡分配;四是坝系的安全系数小于1。建设目标实现后,坝系进入相对稳定状态,在设计频率100年一遇的暴雨洪水标准下,坝系安全系数等于0.94,坝地种植的高秆作物可以达到保收,此时,坝系安全和坝地保收能力可趋向于统一。

Relative stability analysis of dam system in Xiheidaigou Watershed

In order to provide scientific basis for the planning and feasible study,the relative stability of dam system has been studied and analyzed according to the observed data of present control situation in Xiheidaigou watershed and its relative factors which influenced the stability of dam system.The results show that the silted area is one of the basic conditions,but not the sole condition.Judging whether or not dam system has brought about relative stability must satisfy with the concourse of four conditions.There should be 7.8?hm²/km² of silted land area.The coefficient of relative stability of dam system should reach 1/12.7.After the dam system has been operated for 15 years the dam should be maintained and heightened in each 3 or 5 years so that the dam system's capacity of preventing and controlling flood could be holding or larger than the standard of only once in 100 years.There should be 0.3 main dam and 1.0 check dam within one kilo squire meter.The overall layout and structure of dam system should be rational so that storm flood could be distributed harmoniously.The safety coefficient of dam system should be smaller than 1.After accomplishing the construction target dam system has gotten into the stage of relative stability.Under the flood standard of only once in 100 years,the safety coefficient of dam system（Icp） is equal 0.94,the high stalk crops that have been planted in dam land can harvest.The dam safety and capacity of harvest in dam system can be tending to unify.