傍山和深挖方的渠段,由于渠外侧地下水压力的影响,往往使渠内防渗层边坡下部及底板遭到破坏,如混凝土开裂,柔毡或塑料薄膜鼓泡掉块,严重的甚至引起滑坡。为了防止这种现象发生,以往做法是在渠内埋设排水竹管或预留排水孔,这样虽能导排出地下水,但给渠内水流形成了向外渗漏的人为通道,难以达到节约用水的目的;同时,由于集中渗漏,易于形成塌洞,使衬砌体架空,给管理和维修工作带来后患。 针对这种情况,湖南省水科所研制的“ZM系列渠道防渗减压阀”(下称减压阀),能有效地排除地下水压力对防渗层的破坏,而渠内过水时不外渗。 它的基本构造是:在聚氯乙烯硬塑管模内,装有单向排水的逆止阀,管的两端用土工织物封盖,如附图所示。 该装置对已经或正待衬砌的各种材料的渠道防渗层都适用;且可用于保护塘坝或涵 Due to the influence of groundwater pressure outside the canal, the underground sections of the seepage-proof slope and the floor of the canal are often damaged, such as cracking of concrete, bubbling of soft carpet or plastic film, serious Even caused landslides. In order to prevent this from happening, in the past, drained bamboo pipes or drainage holes were reserved in the drainage channels. Although this led to the drainage of groundwater, the outflow of water to the canal formed a man-made channel which made it difficult to save water Purpose; the same time, due to concentrated leakage, easy to form collapse hole, so that the overhead lining, bring management and maintenance work troubles. In view of this situation, “ZM Series Channel Anti-seepage and Pressure Reducing Valve” (hereinafter referred to as pressure reducing valve) developed by Hunan Water Science and Technology Co., Ltd. can effectively eliminate the damage caused by groundwater pressure to the anti-seepage layer. Extravasation. Its basic structure is: in the PVC rigid plastic pipe mold, equipped with one-way drainage check valve, the ends of the tube covered with geotextile, as shown in the figure. The device is suitable for lining impermeable layers of various materials that have been or are being lined; and can be used for protecting ponds or culverts