可用于造腔试验的型盐相似材料研究

用相似理论推导盐岩力学特性相似模型，得到力学参数的相似判据。以重庆北碚盐矿作为相似材料主料，考虑压制力、盐粉含水率、盐粉粒径、盐粉不溶物含量4个影响因素，开展型盐材料配比试验。结果发现：北碚天然盐粉16目粒径，在105～110 ℃烘箱中烘干24 h，100 MPa的压制力，并保压30 min，制备出来的型盐其单轴力学性质与金坛盐岩相似，且满足相似模型的要求。用最佳配比制备型盐，研究其在常温时上溶、侧溶的溶解特性，及60 ℃，70 ℃，80 ℃时侧溶的溶解特性。结果表明：型盐在上溶、侧溶时，其溶解速率都比天然盐岩小，分别为天然盐岩溶解速率的0.75，0.81倍；在溶液温度60 ℃，70 ℃，80 ℃的情况下，其溶解速率同样比天然盐岩小，分别为天然盐岩溶解速率的0.88，0.74，0.78倍。该相似材料配比可用于制备大尺寸型盐来模拟盐岩造腔全过程，对造腔模拟研究具有重要作用。

STUDY OF SYNTHETIC ROCK SALT SIMILAR MATERIALS FOR SOLUTION MINING TEST

The mechanical property of rock salt similar model is derived from the similarity theory in order to obtain the similarity criteria of the mechanical parameters. Considering the four factors，i.e. pressing strength，water ratio，salt particles with different diameters and insoluble in salt，Chongqing Beibei salt mine is chosen to make a materials proportion test. The results show that Chongqing Beibei salt filtered into 16 mesh size without gypsum powder when putting it in the 105 ℃–110 ℃ oven for 24-hour drying，under 100 MPa pressing strength while keeping the pressure for 30 minutes，then the synthetic rock salt that can meet the requirement of uniaxial mechanical similar model of Jintan rock salt was produced. This study makes a research on the dissolution characteristics of synthetic rock salt produced by the best materials proportion whilst dissolve angle is 90° and 180° in regular temperature as well as in 60 ℃，70 ℃ and 80 ℃. The results show that the dissolution rate of molded rock salt was 0.75 times as quick as that of natural rock salt when the angle was 90º and remains 0.81 times under 180° angels in regular temperature. What?s more，the dissolution rate of molded rock salt was 0.88，0.74 and 0.78 times as quick as that of natural rock salt whilst temperature was 60 ℃，70 ℃ and 80 ℃ respectively. The similar material proportion can be used for the making of large-size synthetic rock salt to simulate the rock salt cavity formation process，thus it has an important effect on the cavity simulation study.