Abstract
In order to explore the effect of different rock content on shear strength and soil-rock mixture, 21 large-scale single-shear tests were conducted using advanced large-scale single shear tester. A total of 7 test samples from 0% to 80% of stone content were designed and tested at three different normal pressures of 100, 200, and 300. Based on the experimental results, the relationship between stone content and shear strength, and shear characteristics of soil-rock mixture was analysed. The experimental results show that under the same normal pressure, the internal friction angle and cohesion of soil-rock mixture increase first and then decrease with the increase of stone content. When the soil-rock mixture is between 40% and 50%, the shear strength is the highest. The results show that the shear strength of soil-rock mixture is affected by the porosity ratio of soil-rock mixture, and at the same time, the structure and dominant particles in soil-rock mixture also change with the increase of stone content. When the content of stone is between 0% and 20%, the fine aggregate dominates in the soil-rock mixture, and the soil-rock mixture is suspended and compacted structure. At this time, the shear strength of the soil-rock mixture is similar to that of the matrix particles. When the content of stone is 20%~50%, the soil-rock mixture is a skeleton pore structure. With the increase of the amount of stone, the skeleton of the soil-rock mixture gradually forms and the occlusal force between the particles increases, making the cohesion and internal friction. The horns have been significantly improved; when the amount of rock content exceeds 50%, the soil-rock mixture exhibits a dense skeleton structure, the porosity starts to increase and the fine granules begin to drastically decrease, and the fine aggregate cannot fully fill the pores between the blocks. The shear strength of soil-rock mixture began to decline.
