摘要
用挖泥船吹填堵口复堤,具有施工简便、速度快、质量好等优点,此法自90年代以来在洞庭湖区得到较多应用。施工程序是首先水下冲填,接着分池分边、轮回冲填,最后进行人工填筑、整形结顶,此法1984年在汉寿县马家铺堤段试验成功后,进而在许多地方推广。洞庭湖区多数用此法堵口复堤段在1998年特大洪水时,在挡水深10m以上情况下,安全无恙,没有出现渗漏管涌和滑坡险情。用挖泥船吹填筑堤应注意做好泥沙沉淀池的设计和排水固结。沉淀池的长、宽、深设计得当才能使吹填的土料沉淀下来,及时排水固结对缩短工期起关键作用。用此法吹筑大堤的填土质量满足堤身边坡稳定要求。如马家铺堵口大堤边坡稳定系数Fs8=1.647,属安全。从工程造价看,用挖泥船吹填筑堤,每立方米土价为8～10元。用人工或机械等方法修堤,每立方米土价为25～30元。
Use of dredgers to silt up dyke breaches possesses advantages of simple,convenient and rapid construction,and good quality,etc..Since 1990s this method has found more application in Dongting lake area.The construction procedure for this method is:(1) underwater silting up;(2) alternative silting up in basins;(3) earth-filling by manual labor,taking shape and levelling dyke top.This construction method has been popularized in many places since its successful trial use at Majiapu dyke section in Hanshou county in 1984.Most of the dyke sections restored by using this method in Dongting lake area safely resisted flood with water head higher than 10 m during the 1998 flood period,and no leakage,piping and slope failure occurred.In silting up dyke breaches by dredgers,more attention should be paid to the design of sediment silting basins and to the drainage and solidification of dykes.The length,width and depth of sediment silting basins should be designed to be reasonable in order to make the filled earth material settle down soon.Timely drainage and solidification play a key role in shortening the construction period.The quality of the earth material filled by using this method satisfies the requirement of dyke slope stability.For example,the dyke slope stability factor of the restored Majiapu dyke is equal to 1.647,being in safety.From the point of view of the project cost,the price per cubic meter of earth material filled by using dredgers is 8～10 yuan,while by using manual labor or other machinery it is 25～30 yuan,so the economic benefit of using dredgers to silt up dyke breaches is obvious.
出处
《人民长江》
EI
北大核心
2000年第1期13-15,共3页
Yangtze River
关键词
吹堤筑堤
挖泥船
堵口复堤
排水固结
洞庭湖
silting method for embankment
dredger
dyke breach repair
drainage and solidification
case history
Dongting lake
