發(fā)布時間：2019-02-20 19:23

【摘要】：高溫作用會導(dǎo)致巖石內(nèi)部結(jié)構(gòu)發(fā)生變化,并對其熱物理性質(zhì)產(chǎn)生顯著影響,因此,研究高溫作用后巖石熱物理性質(zhì)的變化規(guī)律對地?zé)嵯到y(tǒng)及存在熱流傳播問題的地下工程具有指導(dǎo)意義。實(shí)驗以高溫作用后砂巖、灰?guī)r為研究對象,利用熱常數(shù)分析儀研究了砂巖、灰?guī)r熱導(dǎo)率隨溫度的變化特征,并結(jié)合巖石微觀結(jié)構(gòu)特性,從礦物受熱的微觀機(jī)理出發(fā),對巖石熱導(dǎo)率變化的內(nèi)在機(jī)理進(jìn)行了初步探討。結(jié)果表明,砂巖熱導(dǎo)率可分為25~100℃、100~400℃、400~600℃和600~900℃四個階段,灰?guī)r熱導(dǎo)率可分為25~100℃和100~400℃兩個階段,砂巖、灰?guī)r在25~400℃間由于水分的蒸發(fā)熱導(dǎo)率整體變化較快,400℃以后礦物發(fā)生相變及分解、熔融等物理化學(xué)反應(yīng),從而微裂縫發(fā)育、延伸,并連接形成宏觀裂隙,砂巖熱導(dǎo)率急劇下降,灰?guī)r內(nèi)部結(jié)構(gòu)較完整,微裂隙發(fā)育較少,熱導(dǎo)率基本穩(wěn)定。
[Abstract]:The high temperature will lead to the change of the internal structure of the rock and have a significant effect on its thermo-physical properties. The study of the variation of the thermal physical properties of rocks after high temperature action is of great significance to the geothermal system and underground engineering with heat flux propagation problem. The thermal conductivity of sandstone and limestone under high temperature is studied by means of thermal constant analyzer. The characteristics of thermal conductivity of sandstone and limestone with temperature are studied, and the microstructure of rock is combined with the microscopic mechanism of mineral heating. The internal mechanism of rock thermal conductivity variation is discussed. The results show that the thermal conductivity of sandstone can be divided into four stages: 25 鈩，

本文編號：2427172