水平定向钻进铺管技术在盐碱地改良中的应用

土壤盐碱化作为一种渐进性环境地质灾害，已严重制约着人类生活与社会经济的发展，对盐碱地实施改良和微咸水开发利用已成为世界关注的热点。以往的盐碱地改良多用明渠、暗管排水、暗管结合大口径竖井抽排、种植耐碱性植物等方法，明渠及埋设暗管对地表的开挖破坏性极大、且排水量及适用深度有限、植物改良存在周期长、费时费力等诸多缺点。水平定向钻进铺管技术可将滤水管以水平或近似水平安装在含水层中（水平井），可垂直于含水层流向长距离铺设，与传统改良方式相比能获得较大的出水量、成本低、且施工对环境影响小等诸多优势，工程实例证明，该施工工艺技术为盐碱地改良、地下咸水开发利用、浅层低渗透性地下水资源开采等提供了较理想的工艺方法。

Application of HDD Pipelaying Technique in Saline Soil Improvement

As a gradual environmental geological disaster, soil salinization severely restricts the human life and the development of social economy, the improvement of saline alkali soil and the development & utilization of brackish water have become the hotspot in the world. Open channel, subsurface drainage and subsurface drainage combined with large diameter vertical shaft and alkali resistant plant were used for saline alkali soil improvement, but open channel and buried underground pipe have great damage to ground surface with disadvantages of limited water displacement and applicable depth, long plant improvement cycle and being time-consuming. By horizontal directional drilling (HDD), screen pipe can be horizontally or nearly horizontally installed in the aquifer and be laid perpendicular to the aquifer flow in a long distance. Compared with the conventional tube well drilling, there are advantages of larger water yield, low cost and small impact on the environment. The engineering example proves that this construction technology is ideal for saline alkali soil improvement, development