岩石在酸化环境下的强度损伤及其静态加速模拟

在不同质量百分比(1.0%,5.0%及10.0%)的3种酸溶液(H2SO4,HNO3和HCl)中,对大理岩和辉绿岩的水岩作用进行了静态长时(900d)加速浸泡试验模拟,分析了岩石单轴抗压强度、劈裂法抗拉强度和表面肖氏硬度的损伤对酸的敏感性和损伤机制。研究结果表明,在静水环境下,岩石强度损伤、硬度损伤及腐蚀速率与H 浓度及浸泡时间成非线性关系,岩石腐蚀所产生的环境效应不仅与岩性、酸种和H 浓度有关,而且与新成盐是否发生水解有关。

ROCK STRENGTH DETERIORATION UNDER ACIDIFIED CONDITIONS AND ITS STATIC ACCELERATED SIMULATION

Aimed to understand how rocks get deteriorated under acidified conditions,accelerated simulations of water-rock interaction for marble and diabase have been carried out continuously in static water surroundings with different acids (H2SO4,HNO3 and HCl) of different contents (1.0%,5.0% and 10.0%) for 900 days.The sensitivity of the deterioration of unconfined compressive strength(UCS),tensile strength and Shore hardness to acid types and acidity,and deterioration mechanism are analyzed.The results seem to indicate that strength deterioration,surface hardness deterioration and eroded rate will nonlinearly increase with the concentration of H and acid treatment time;and environmental effect of the simulation conditions is directly correlated to the lithology,acid types and the concentration of H as well as further dissolution of the new salts in water.The sensitivity to both strength deterioration and hardness deterioration of marble and diabase under individual acid conditions is different from that under mixed acid surroundings.In the case with individual acid,vitriol and nitric acids are relatively sensitive to marble and diabase when the content of acid is less than 5.0%.However,the sensitivity will decrease and the effect on deterioration will become stable when their content is more than 5.0%.It shows that different acid types play different roles in deterioration of carbonate and silicate rocks.In the case of mixed acids,the deteriorations of strength and hardness of marble gradually increase with the increase of the content of vitriolacid.However,the activities of vitriol,nitric acid and hydrochloric acid are equal for diabase.It shows that the mechanisms of erosive function in carbonate rock are different from that in silicate rock under the mixed acid conditions.Generally,the deteriorations of strength and hardness in both marble and diabase are more intensive in the case of mixed acids than that in the individual case.Further,in both cases,the deteriorations of marble are more intensive than those of diabase,and the damage in tensile strength,UCS,and Shore hardness will decrease in order.