新建天陇铁路红层路堑边坡特征和防护研究  

Study on Characteristics and Protection of Red Bed Cutting Slopes in the Newly Built Tianshui-Longnan Railway

作　　者：刘春刚[1] LIU Chungang(China Railway First Survey and Design Institute Group Co.,Ltd.,Xi'an 710043,China)

机构地区：[1]中铁第一勘察设计院集团有限公司,西安710043

出　　处：《铁道勘察》2025年第2期121-128,135,共9页Railway Investigation and Surveying

基　　金：国家重点研发计划项目(YFC1504904)。

摘　　要：为研究甘肃地区红层岩体水敏劣化和对松弛劣化特性对于路基工程影响,对新建天陇铁路不同类型红层路堑边坡进行地质力学模型划分,并从细观层面研究不同地质年代红层岩体物理力学特性;探究红层岩体路堑边坡在开挖卸荷和雨水软化两个致灾因子影响下破坏模式,从而针对性采用不同设计思路和风险防范方法。研究表明,红层岩体地质年代和成因对红层岩体力学性质影响很小;在降雨、地表水和地下水的影响下,红层岩体力学强度会出现不同程度降低,同时会加剧浅表层红层岩体的风化和剥落;开挖卸荷是红层路堑边坡破坏主要原因,无论是顺层边坡还是反倾边坡,开挖卸荷改变整个边坡应力分布,导致坡脚产生应力集中,从而引起边坡失稳。为防止浅表层风化及破坏,需对红层岩体边坡坡面进行加固和防护。To investigate the impact of water-sensitive degradation and relaxation deterioration of red-bed rock masses on linear engineering in the Gansu region,geological-mechanical model zoning was carried out for various types of red-bed cut slopes along the newly constructed Tianshui-Longnan Railway.The study also examined the physical and mechanical properties of red-bed rock masses from different geological periods at the microscale.Furthermore,the failure modes of red-bed cut slopes under the influence of two disaster-inducing factors,such as excavation unloading and rainwater softening were explored,providing a basis for the development of targeted design approaches and risk mitigation strategies.The research indicates that the geological age and genesis of red-bed rock masses have minimal impact on their mechanical properties.However,under the influence of rainfall,surface water,and groundwater,the mechanical strength of red-bed rock masses decreases to varying degrees,while weathering and spalling of the superficial layers are exacerbated.Excavation unloading is identified as the primary cause of red-bed cut slope failures.Regardless of whether the slope is dip or anti-dip,excavation unloading alters the stress distribution across the slope,leading to stress concentration at the slope toe,which triggers slope instability.To prevent superficial weathering and failure,it is essential to reinforce and protect the slope surfaces of red-bed rock masses.

关 键 词：铁路 路基 红层边坡 力学模型 水敏劣化 松弛劣化 

分 类 号：U212[交通运输工程—道路与铁道工程] U213.1