岩爆相似材料的最优配比试验研究

Experimental study on optimum proportion of similar material for rock burst

为了对云南某矿山深部白云岩进行相似材料优选,以细砂、水泥、石膏、硼砂和减水剂为原料,采用正交试验原理确定了以石膏水泥比、掺砂率、掺水率、硼砂含量为影响因素的4因素4水平正交设计方案。对试件模型进行单轴抗压和巴西劈裂试验,得到相似材料抗压及抗拉强度、抗压抗拉比、弹性模量,通过方差和极差分析研究了各影响因素对研究指标影响的显著性。研究结果表明:掺砂率对单轴抗压强度和抗拉强度的影响较显著,单轴抗压强度随石膏水泥比和掺砂率的增大逐渐降低,抗拉强度随掺砂率的增大逐渐降低;抗压抗拉比随着掺水率的增加逐渐增加;弹性模量随着石膏水泥比的增加逐渐下降。通过多元线性回归分析得出白云岩相似材料配比的经验方程,经计算得出该矿山深部白云岩相似材料的最优配比为:石膏水泥比3. 1∶1,掺砂率59%,掺水率20%,硼砂含量0. 4%,减水剂含量0. 3%。

In order to carry out the optimization of similar material for the deep dolomite of a mine in Yunnan, taking the fine sand, cement, gypsum, borax and water reducing agent as the raw materials, an orthogonal design scheme containing four factors and four levels with the ratio of gypsum and cement, sand mixing rate, water mixing rate and borax content as the in- fluencing factors was determined by using the orthogonal test principles. The uniaxial compression and Brazilian splitting tests were carried out on the specimen model, then the compressive strength and tensile strength, the ratio of compressive and ten- sile, and the elasticity modulus of the similar material were obtained, and the significance of the influence on the research in- dexes by each influencing factor was studied by the variance and range analysis. The results showed that the influence of sand mixing rate on the uniaxial compressive strength and tensile strength was more significant. The uniaxial compressive strength decreased gradually with the increase of the ratio of gypsum and cement and the sand mixing rate, the tensile strength de- creased gradually with the increase of the sand mixing rate, the ratio of compressive and tensile increased gradually with the increase of the water mixing rate, and the elasticity modulus decreased gradually with the increase of the ratio of gypsum and cement. The empirical equation about the proportion for the similar material of dolomite was obtained through the muhivariate linear regression analysis, and the optimum proportion for the similar material of the deep dolomite in this mine obtained by the calculation was： the ratio of gypsum and cement as 3.1 ： 1, the sand mixing rate as 59% , the water mixing rate as 20% , the borax content as 0.4% , and the content of water reducing agent as 0.3%.