發(fā)布時(shí)間：2018-09-14 07:57

【摘要】：作為龍游石窟的主要成分,龍游砂巖往往在高溫和高應(yīng)變率條件下會(huì)遭到破壞。因此高溫下龍游砂巖動(dòng)態(tài)斷裂韌度的研究對(duì)龍游石窟的保護(hù)有重要意義。針對(duì)不同熱處理溫度下的龍游砂巖,采用微米X射線計(jì)算機(jī)斷層掃描技術(shù)分析了砂巖的熱損傷,并運(yùn)用分離式霍普金森壓桿實(shí)驗(yàn)研究了砂巖在加載率8~270 GPa·m1/2/s時(shí)的動(dòng)態(tài)斷裂韌度。實(shí)驗(yàn)表明,龍游砂巖的斷裂韌度隨著加載率的增加而增加。在相同的加載率下,除450℃以外,斷裂韌度隨著熱處理溫度的升高而減小。結(jié)合準(zhǔn)靜態(tài)和動(dòng)態(tài)實(shí)驗(yàn)數(shù)據(jù),建立了描述龍游砂巖動(dòng)態(tài)斷裂韌度和加載率以及熱處理溫度關(guān)系的模型。
[Abstract]:As the main component of Longyou grottoes, Longyou sandstone is often destroyed under high temperature and high strain rate. Therefore, the study of dynamic fracture toughness of Longyou sandstone at high temperature is of great significance to the protection of Longyou Grottoes. Thermal damage of Longyou sandstone under different heat treatment temperature was analyzed by micron X-ray computed tomography. The dynamic fracture toughness of sandstone at loading rate of 870 GPa / 1 / 2 / s was studied by split Hopkinson pressure bar experiment. The experimental results show that the fracture toughness of Longyou sandstone increases with the increase of loading rate. At the same loading rate, the fracture toughness decreases with the increase of heat treatment temperature except 450 鈩，

本文編號(hào)：2242058