Experimental study on fractal characteristics of coarsegrained soil filler for high-speed railway subgrade

Abstract

This paper takes coarse-grained soil filler of high-speed railway subgrade as object of study, completes a series of coarse grained soil compaction tests under different moisture content with electric heavy compaction apparatus type YX-30, and obtains the granularity fractal distribution curve with coarse-grained granularity fractal model. The result shows that coarse-grained soil filler has obvious fractal characteristics after compaction, and particle breakage fractal dimension between 2.61-2.82. With the increase of fractal dimension, the maximum dry density increases first and then decreases, and the maximum fractal dimension is under the optimum water content. The coarse-grained soil with high clay content has lower particle size and smaller fractal dimension before and after compaction. Water content and clay content are two important factors that affect the crushing of coarse-grained soil. The effect of clay content on particle size is more significant than that of clay content.