水平定向钻顶管结合工法的可行性分析

Feasibility Analysis on Combining Work of Horizontal Directional Drilling and Pipe Jacking

水平定向钻工法和顶管工法都具有高效、环保、不影响交通、不开挖地表等优点,但对于穿越距离长、地形地质条件复杂等具有挑战性的工况,单一穿跨越形式由于其自身工艺的局限性很难满足工程实施要求,如果采用联合穿跨越,可充分利用各种穿跨越方式的技术优势,有效降低施工难度、节省投资、更有利于工程安全顺利实施。目前国内外对于这种联合穿跨越结构形式应用较少,理论研究较为匮乏,未形成成熟的理论和施工技术,针对水平定向钻和顶管工法结合的可行性进行了分析,并且针对最关键的管道曲率半径和顶管始发井长度进行了定量的分析。计算结果表明,钢管不适合直接从顶管始发坑中回拖,而PE管道在直径较小和深度不大时能直接通过顶管始发井进行回拖,节省工程成本。

Both of horizontal directional drilling（HDD）and pipe jacking（PJ）are highly efficient and,environmentally friendly with no traffic interdiction and no open cut,but when involved into some long distance,complicated topographic and geological conditions,the single method will be challenged due to the technology limitation which may lead to serious engineering problems.Hence,the joint technology between HDD and PJ was taken into account to address the applicable conditions and technical advantages,reduce the difficulty of construction,and save investment.This paper focuses on the feasibility of this combined method by analyzing the most critical radius of curvature.The results show that steel is not suitable for direct pullback originating from pipe jacking pit,while the smaller diameter PE pipe with small diameter and depth can be pullback directly through pipe jacking pit and save engineering costs.