Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect  

作　　者：CHENG Yun SONG Zhanping XU Zhiwei YANG Tengtian TIAN Xiaoxu 

机构地区：[1]School of Civil Engineering,Yancheng Institute of Technology,Yancheng 224051,China [2]School of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China [3]Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering,Xi'an 710055,China [4]China Railway Construction Bridge Engineering Bureau Group Co.,Ltd.,Tianjin 300300,China

出　　处：《Journal of Mountain Science》2024年第3期1058-1074,共17页山地科学学报（英文）

基　　金：National Natural Science Foundation of China(No.52178393);2023 High-level Talent Research Project from Yancheng Institute of Technology(No.xjr2023019);Open Fund Project of Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering(Grant No.YT202302);Science and Technology Innovation Team of Shaanxi Innovation Capability Support Plan(No.2020TD005).

摘　　要：The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass.

关 键 词：Hard siltstone Failure mechanism Stratification effect Infrared radiation characteristic Temporal-damage mechanism DISSIMILATION 

分 类 号：U298[交通运输工程—交通运输规划与管理] U457[交通运输工程—道路与铁道工程]