物化型软岩块体崩解特性差异的试验研究

Experimental study on block disintegration difference of physicochemical soft rock

通过对以高岭石和蒙脱石含量为主的2种软岩崩解特性的对比试验,运用分形几何理论分析了不同初始块度和循环崩解次数的2种软岩崩解颗粒的粒径分布特性,并就2种软岩的崩解特性差异进行了探讨.研究结果表明：随初始块度S和循环崩解次数n的增加,软岩的崩解性增强,崩解颗粒小粒径化.以高岭石含量为主软岩崩解主要是由结构缺陷中空气被水挤压产生超张应力,使原结构缺陷扩容引起,崩解后以大粒径颗粒为主,其粒径分布的分维数D为0.8731-1.7642;而以蒙脱石含量为主软岩崩解则主要是由蒙脱石遇水膨胀造成岩体差异膨胀引起,崩解后以小粒径颗粒为主,其粒径分布的分维数D为2.2231-2.7162.

Based on the disintegration comparison tests of two kinds soft rocks which basis composition is montmorillonite and kaolinite, the effects of initial block and disintegration cyclic times on the particle-size distribution characteristics of two kind soft rocks disintegration grain were analyzed by using fractal theory, and disintegration difference of two kind soft rocks was discussed. The results show that disintegration of samples and the total of granule increased with the increase of initial block S and disintegration cyclic times n. Soft rock that clay minerals consist mainly of kaolinite, and its disintegration resulting form inner structure defect expanded which is generated by tension from water squeezing air in defects, the fractal dimension D of disintegration grains distribution are between 0. 873 1 and 1. 764 2, the dominant form of disintegration grain is bigger grain. Soft rock that clay minerals consist mainly of montmorillonite, and its disintegration resulting form block difference swelling which is generated montmorillonite expand by water, the fractal dimension D of disintegration grains distribution are between 2. 223 1 and 2. 716 2, the dominant form of disintegration grain is small grain.