酸性溶液化学腐蚀作用下花岗岩单轴压缩力学性能试验

Tests on mechanical properties of granite under uniaxial compression subjected to chemical corrosion of acidic solution

通过对花岗岩进行酸性溶液浸泡处理,探究酸性腐蚀下花岗岩试块的物理力学性能及微观结构变化。具体方法是花岗岩试块在不同时间(30、60、90 d)、不同p H值(p H值为1、3、5)下经硝酸溶液浸泡后,进行单轴压缩试验,破坏后的碎片使用扫描电子显微镜观察花岗岩试块微观结构。结果表明,酸性溶液对花岗岩试块有劣化效应,主要为分解反应。p H值≤5的硝酸溶液浸泡90 d后,试块单轴抗压强度略有升高,推断是由于分解反应得到的二氧化硅悬浮液脱水后成为硅质胶结物,最终由于胶结作用使得花岗岩单轴抗压强度略有升高。准确且有效的变化规律需要进一步进行试验。

This work studied the changes of physical and mechanical properties and microstructure of granite specimen under acid corrosion through immersion in acid solution. The specific method is as follows. The granite samples were immersed in nitric acid solution of different pH values( pH = 1,3,5) for different time intervals( 30,60,90 days),and then uniaxial compression test was carried out. After destruction,the fragments were preserved and the microstructure of granite rock was observed by scanning electron microscope. The results show that acid solution has a deteriorating effect on granite rock,mainly as a decomposition reaction. When pH ≤5,after immersion in nitric acid solution for 90 days,the uniaxial compressive strength of the test rock will slightly increase. It is inferred that the dehydration of silica suspension from decomposition reaction results in the formation of siliceous cements,and finally cementation makes the uniaxial compressive strength of granite slightly increase. Accurate and effective rules need further experiments.