南水北调中线总干渠京石段渠道衬砌抗浮稳定设计方案讨论

Design of Lining Canal's Stability Against Floatation in Main Canal of the Middle Route of South to-North Water Transfer (from Beijing to Shijiazhuang)

南水北调中线京石段渠道设计中,遇到了当地下水位高于渠底或渠外水位高于渠内水位时,对刚性衬砌渠道将产生渗透破坏问题。由于渠道衬砌厚度很薄,当外水位超过渠内水位0．1～0．15 m时,即可将衬砌板浮起而破坏,这是一个设计条件苛刻而难以稳定安全的棘手问题,初步设计中依据《渠道防渗工程技术规范》(SL18—2004),采取排水减压措施,但遇到了内外水头差大的渠段排水流量大和逆止阀布设数量多等问题。现主要讨论地下排水和其它措施解决渠道衬砌板抗浮稳定设计方案问题。

When the groundwater level is higher than canal base or outside water level higher inside, the rigid lining will be destroyed by percolation. Due to only 0.1-0.2m of the lining thickness of the canal, when the water level outside is 0.1 -0.15m higher than inside, the lining plate will be floated and be destroyed. This is a knotty problem. According as ＂Technique Specification for Seepage Prevention Engineering on Canal＂（LS 18-2004）, the article mainly discusses the design proposal of canal lining plates＇ anti-floating by using under-drainage and other measures.