碳质灰岩热力特性试验研究  

Experimental study on thermal-mechanical properties of carbonaceous limestone

作　　者：田云雷 陈世万 左双英[1] TIAN Yunlei;CHEN Shiwan;ZUO Shuangying(College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学资源与环境工程学院,贵州贵阳550025

出　　处：《人民长江》2021年第10期195-200,243,共7页Yangtze River

基　　金：国家自然科学基金青年科学基金项目(41902301);贵州省科学技术基金项目([2020]1Y185)。

摘　　要：针对岩石热力特性问题,以声发射监测为主要手段,研究了加温冷却和实时加温加载两种条件下碳质灰岩热损伤过程的声发射演化。研究表明:①加热过程中,灰岩在50℃开始出现声发射,至320℃左右时沿层理面炸裂,产生较大声响和冲击力,声发射出现突增,灰岩表现出“热脆性”损伤;②灰岩在两种加热处理条件下,声发射撞击数都会出现局部显著增加阶段,可为确定起裂应力和损伤应力提供支持;③实时加温加载条件下,随温度升高灰岩单轴抗压强度降低;但在加温冷却条件下,300℃处理冷却后,灰岩单轴抗压强度有所增加;④两种加热条件下,灰岩的起裂应力和损伤应力随温度增加而降低。To study thermal-mechanical properties of carbonaceous limestone,we carried out acoustic emission(AE)monitoring test of limestone under two heating processes,the heating and cooling then loading process and the simultaneous heating and loading process.The results show that:①AE events began to emergein heating process at 50℃.The limestone burst into pieces around 320℃along the bedding plane with loud noise,meanwhile AE events increased significantly,characterized as‘thermo-brittleness’damage.②AE increasing stages can be identified during the two loading processes,which is helpful to determination of crack initiation stress and crack damage stress.③The strength of limestone decreased with increasing of temperature in the simultaneous heating-loading process.However,thelimestone’ssingle axial compressive strength increased after 300℃temperature treated in heating-cooling process.④For limestone in the two heating processes,crack initiation stress and crack damage stress both decreased with increasing of temperature.

关 键 词：岩石热力性质 声发射 灰岩 岩石强度 

分 类 号：TU45[建筑科学—岩土工程]