摘要：研究目的：高速铁路对轨道的平顺性要求极为严格，兰新高铁大范围穿越泥岩地段，岩体遇水后易发生 崩解，胀缩性大，引起轨面变形。目前针对膨胀岩（土）的研究主要集中于有砟轨道铁路路基，对无砟轨道路 基却缺乏研究。因此需开展干旱区高速铁路膨胀性泥岩路基处理措施的研究，以满足高速列车的平稳运行要 求。 研究结论：( 1)第三系、白垩系和侏罗系泥岩，成岩作用差，岩质较软，节理裂隙发育，易风化剥落，岩体遇 水易崩解，胀缩性大，具弱A中等膨胀性;（2)泥岩处理需考虑场地大气影响深度的影响；（3)地下水是引起泥 岩膨胀的主要因素，路基处理应采取必要的防排水、保湿措施；（4)本研究成果应用于高速铁路膨胀性泥岩路 基工程，可为同类设计积累丰富经验，同时可为规范修编提供参考依据。

Abstract:Research purposes: High - speed railway has strict requirements for the smoothness of the rails. Lanzhou - Xinjiang high - speed railway passes across a wide range mudstone region，cut the mudstone will disintegrate when meeting water，and it has large swell - shrink characteristic， so it can cause deformation on the surface of rail. The research on expansive rock ( soil) mainly focuses on ballasted track railway subgrade，lack of research on [allastless track railway subgrade. Therefore，it is necessary to carry out research on expansive mudstone treatment measures in arid area for high - speed railway subgrade，to guarantee the high - speed trains running smoothly. Research conclusions:( 1 ) Tertiary， Cretaceous and Jurassic mudstones have poor diagenesis， soft rock， and developmental joint fissure，it is easily weathered and easily disintegrated when meeting water，with larges well - shrink characteristic，weak and medium expansible. (2) Mudstone foundation treatment should consider the influence of depth of field atmospheric effects. (3) Groundwater is the main factor causing the expansion of mudstone， and foundation treatment needs to take necessary measures such as waterproofing，draining and moisturizing. (4) These research results have been successfully applied to high - speed railway with expansion mudstone subgrade， and accumulated rich experience for similar design，meanwhile can provide the reference for compiling some codes.