石灰改良下蜀黏土作为高速铁路路堤填料的动力特性试验研究

Experimental Study on the Dynamic Properties of Lime-Improved Xiashu Loess Utilized as High-speed Railway Embankment Filler

高速铁路对路基填料的工程性质特别是基床结构填料的动力学特性提出了很高的要求。通过室内动三轴试验及现场激振试验,对石灰改良下蜀黏土作为填料的动力特性进行系统的研究,对其作为高速铁路基床底层填料的可行性进行评价。研究结果表明:下蜀黏土经石灰改良后,具有较高的临界动应力值,动载作用下弹性变形及塑性变形较小,满足高速铁路基床底层填料要求。石灰改良下蜀黏土力学特性受相关因素影响,应用过程中,应注意对含水率、压实系数等进行合理控制。

In high-speed railway,there are strict and high demands on engineering properties of subgrade filler,especially dynamic characteristics of subgrade bed structure filler.Based on laboratory dynamic triaxial test and field forced vibration test,the dynamic properties of lime-improved Xiashu loess were systematically researched and the feasibility as the foundation bed filler of high-speed railway was evaluated in this paper.The results show that,the lime-improved Xiashu loess has a higher critical dynamic stress value and the elastic and plastic deformation are smaller under the action of the dynamic load,so it meets the demands of foundation bed filler of high-speed railway.However,the mechanical properties of the lime-improved Xiashu loess are affected by related factors,so its water content and compacting factor should be controlled reasonably in its application.