软岩崩解物颗粒分布特征研究

采集了某高速公路路堤填筑料软岩试样,查明该类软岩的矿物成分和基本物理力学性质。采用洒水和吹晒循环试验,模拟软岩在大气中的自然崩解过程。在试验过程中对崩解物颗粒筛分后进行质量分析,将不同粒径区间内的变化绘成曲线。从其变化趋势发现崩解物颗粒质量变化曲线是自相似的,在统计上是一个分形,并采用盒维数方法计算它的分数维。最终停止崩解时颗粒质量分布曲线的分数维稳定在某一常数。利用稳定分数维作为软岩路基、堤坝修筑施工工艺控制性指标,指导某高速公路路堤工程的施工,获得了质量优良的路基。结果表明分形几何是一种研究软岩崩解机理的有效方法,颗粒质量分布曲线的常分维值可以作为软岩吸水后崩解是否完成的判断标准。

Research on the grading of soft rock crumbling pellets

Soft rock samples,employed as a stuffing material for an expressway roadbed,was collected,and the mineral contents and basic mechanical parameters were measured.The natural collapsing process of soft rocks at the atmosphere was simulated through tests of cyclic watering,blowing and sunning.Changes of soft rock scrap mass in various size ranges was graphed based on sifting measurements.It was found that the graphs are self-similar and statistically a fractal.The fractal dimension value of the curves,calculated by using a box dimension method,tended to be a constant after the collapsing stopped.As a controlling index of stuffing materials for construction of expressway roadbed and dyke,the constant fractal dimension was employed to supervise the construction.The results indicate that fractal geometry is an effective approach to study the collapse mechanicsm of soft rock,the constant fractal dimension value of the rock mass distribution curve can be regarded as a criterion to check if the collapse process of soft rocks after absorbing water has indeed ended.