摘要
以仓上露天矿坑边坡为研究对象,研究地下水溶液、露天矿坑水溶液以及矿坑水位升降引起的干湿循环作用对蚀变岩石力学性质的影响。现场采取地下水和矿坑水溶液,分析水中赋存的阴阳离子,并测得各溶液样本的pH值。通过配比不同水化学溶液及进行不同干湿循环作用下的岩石力学试验,探究水化学作用及干湿循环作用对仓上露天矿坑边坡岩石的力学特性损伤特征。结果表明:地下水溶液呈明显的酸性,同一酸性条件下,随着干湿循环次数的增大,蚀变岩的损伤程度逐渐变大,酸性增强加剧蚀变岩的损伤程度,酸性越强(pH越小),试件的强度降低幅度越大,干湿循环次数最大(n=20),在不同pH下(pH=2,4,7),试件强度降低幅度逐渐增大;酸性最强条件下(pH=2),随干湿循环次数下(n=1,5,8,15,20)增加,试件强度降低幅度也逐渐增大。水化学作用及干湿循环是影响蚀变岩力学特性的重要因素。根据对结果深入分析,建立岩石抗剪强度参数的损伤变量。研究成果为边坡工程的稳定性分析提供基础,具有较强的工程实践价值。
Taking the open-pit slope in Cangshang as the research object, the drying-wetting cycle was caused by water solution in underground, open-pit mine, as well as rise and fall of water level, and its influence on the mechanical properties of altered rock was studied. By taking groundwater and mine water, the zwitterion in water was analyzed and the pH value of each solu- tion sample was measured. The diverse chemical solution was prepared and the mechanical tests under different drying-wetting cycles were carried out~ so as to explore water chemistry reaction and drying-wetting cycle on the damage characteristics of me- chanical properties of the slope rock in Cangshang. The results showed that the underground water presented obvious acidity. Under the same acidic condition, the damage extent of altered rock gradually increased with the number of drying-wetting cycle. And the increasing acidity would intensify the damage degree of altered rock. The stronger acidity was （smaller pH）, the grea- ter reduction of strength was. Under different pH values （pH= 2/4/7） and the largest drying-wetting cycle number（n = 20）, the reduction of strength was gradually improved. Under the strongest pH value（pH= 2）, the reduction of strength also pres- ented increasing trend with the drying-wetting cycle number of 1,5,8,15 and 20 in sequence. Tests showed that water chemis- try reaction and drying-wetting cycle were the important factors influencing the mechanical properties of altered rock. Based on the deep analysis on the results, the damage variable of rock about shear strength parameters was proposed. The study results provided a basis for the stability analysis of slope engineering, with great practical value.
出处
《矿业研究与开发》
CAS
北大核心
2017年第1期98-102,共5页
Mining Research and Development
关键词
蚀变岩
力学特性
水化学作用
干湿循环
露天矿坑
尾矿库
Altered rock
Mechanical properties
Water chemistry reaction
Drying-wetting cycle
Open-pit tailings pond
