云南泸西皮家寨岩溶大泉束流调压壅水开发示范

皮家寨岩溶大泉为上升泉，流量1072．75～1957．5L／s，出露于岩溶盆地边缘槽谷底部松散土层覆盖区，出口及天然径流途径位置低下。根据该泉所处的具体水文地质及工程地质条件，构思设计了新颖的岩溶大泉束流调压壅水技术方案。方案利用了皮家寨岩溶大泉较高的承压水头和下游存在弱透水岩体、上覆弱透水盖层的有利条件，采用帷幕灌浆形成地下防渗帷幕，与地上束流调压池联合，通过开、闭束流调压池上的引水闸和泄水闸调节水位，对大泉进行束流调压壅水开发，使水位壅高，就势将水流输往更高的地区，实现自流引水灌溉。示范工程的建成不仅取代了原有的提水泵站，节约了抽水费用，而且还消除了下游低洼地带农田的长期积水危害。 

Water resource exploitation from big karst spring by flow narrowing-water pressure adjusting-water table raising -- A case in Pijiazhai spring, Luxi county, Yunnan

Water resource and energy resource are in short supply at present, so it is valuable to exploit more hydropower from ascending spring. This paper is to offer an effective demonstration to the exploitation of karst ascending spring. The Pijiazhai big karst spring is an ascending spring of 1 072.75～1 957.5L/s in discharge. Its outflow point is at a flat karst valley bottom in the upper part of the Luxi karst basin. The outflow point and runoff way are lower in elevation than the fields and the villages. According to the particular hydrogeologic and engineering geologic conditions, the original engineer technique program by narrowing flow, adjusting water pressure and is designed for the exploitation of the spring. The engineer design takes benefits of favorable conditions such as the higher confining water table, the weak permeable karst zone at the lower reaches and the superjacent impermeable soil layer around the spring outflow point. The engineer made up of the seepage-proof grouting curtain and the flow narrowing, water pressure adjusting tank. The water level is adjusted by opening and closing the lock gate on the tank to realize raising the water table and transporting the water to higher elevated area, and as a result enabling the spring an artesian irrigation source. The demonstration engineer now has replaced the former 17 pumping stations and eliminated the water logging hazards at the area downstream Pijiazhai spring.