振动荷载下铁路路基粗颗粒土动应变试验研究  

Experimental Study on Dynamic Strain of Coarse Soil in Railway Subgrade Under Vibration Load

作　　者：张书軍 Zhang Shujun(ChinaRailway 12th Bureau Group 3rd Engineering Co.Ltd.,Taiyuan,Shanxi 030024)

机构地区：[1]中铁十二局集团第三工程有限公司,山西太原030024

出　　处：《江西建材》2024年第12期276-278,284,共4页

摘　　要：为了提升铁路路基的抗变形能力,文中通过三轴持续振动试验系统,分析围压、含水量、动应力对铁路路基粗粒土动应变的影响。结果表明,动应力水平越高,路基粗颗粒土累积动应变越大;动应力为100 kPa时,稳定阶段动应变值约为50 kPa时的8.5倍;累积应变随荷载作用次数变化曲线可以划分为衰减型、临界型和破坏型。围压值越大,路基粗颗粒土累积动应变值越小且随荷载作用次数的增加速率越小;围压15 kPa时,稳定阶段累积动应变值约是60 kPa时的4.3倍;相同条件下,与饱和土相比,非饱和土产生的累积动应变越小,即更不易发生破坏。In order to improve the deformation resistance of railway roadbed,the effects of confining pressure,water content and dynamic stress on the dynamic strain of coarse-grained soil of railway roadbed were analyzed through a triaxial continuous vibration test system.The results show that the higher the dynamic stress level is,the greater the cumulative dynamic strain of coarse grained soil is.When the dynamic stress is 100 kPa,the dynamic strain value at the stable stage is about 8.5 times that at 50 kPa.The cumulative strain variation curve with the number of loads can be divided into decay type,critical type and failure type.The larger the confining pressure is,the smaller the cumulative dynamic strain value of coarse grained soil is and the smaller the rate with the increase of load times is.When the confining pressure is 15 kPa,the cumulative dynamic strain value in the stable stage is about 4.3 times that at 60 kPa.Under the same conditions,the cumulative dynamic strain of unsaturated soil is smaller than that of saturated soil,that is,it is less prone to failure.

关 键 词：铁路路基 粗粒土 三轴试验 振动荷载 动应变 

分 类 号：U239.9[交通运输工程—道路与铁道工程]