Optimization of Drainage Schemes for the Dike Strengthening by Warping Construction Project in the Qinhe River under Restricted Drainage Condition

摘要

Dike strengthening by warping construction is one of the main construction modes for the standardized dike construction of mainstream and tributaries in the lower reaches of the Yellow River, and whether the drainage in the dike strengthening by warping construction is smooth is closely related to the safety of dike project. Restricted by topographic conditions and construction conditions, existing drainage schemes are not applicable to the Qinhe River (the Yellow River’s largest tributary) Flood Prevention Project Wuzhi Section, which is next to farm cottage. Therefore, in this paper a field test was carried out using three drainage schemes---“L” type PVC seepage drainage pipes through dike, “L” type perforated PVC seepage drainage pipes coated with geotextile and geotextile drainage grilles. The drainage velocity, silt retaining effect, water level in the silt area, dike body deformation and other key indicators were obtained through field monitoring, and the safety and stability of the dike strengthening by warping construction project were verified by numerical calculation. The field test results showed that the drainage effect of the “L” type perforated PVC seepage drainage pipes coated with geotextile and geotextile drainage grilles was obviously better than that of the “L” type PVC seepage drainage pipes through dike, but the geotextile drainage grilles had advantages in silt retaining effect, construction convenience, cost, and improvement. The field test results can provide a reference for the quick drainage design and construction of dike back deposited with silt of the dike strengthening by warping construction project in the Yellow River.