Measurement of breakage energy of coarse granular aggregates

Abstract

Particle breakage of coarse granular aggregates changes its structure directly, influencing its dilatancy and friction angle. In the course of shearing, normal stress and shear stress do work on volume strain and shear strain. This energy is transformed into particle elastic energy storage, particle friction energy consumption, work done by particle dilatancy and particle breakage energy. The accurate measurement on breakage energy of coarse granular aggregates in the course of shearing aims that it provides a method to analyze the particle breakage influence on constitutive relation in the perspective of energy, creating conditions for development of coarse granular aggregates constitutive relations considering particle breakage. The breakage energy of coarse granular aggregates in the course of shearing is calculated by analyzing the results of the coarse granular aggregates in triaxial compression test. The results indicate that the breakage energy during triaxial tests is mainly influenced by confining stress and friction coefficient.

粗粒土的顆粒破碎直接改變了土體本身結構,對粗粒土的剪脹和內摩擦角都會產生影響。在土體剪切過程中,體積應力和剪切應力在體積應變和剪切應變上做功,這部分能量在剪切過程中轉化為顆粒的彈性儲能、顆粒間的摩擦耗能、顆粒剪脹時對外做功和顆粒破碎耗能4部分。準確計算剪切過程中粗粒土破碎耗能的目的是:從能量角度分析顆粒破碎對土體本構關系的影響,為建立考慮顆粒破碎的粗粒土本構關系創造條件。通過分析粗粒土的常規三軸試驗數據,計算得到了剪切過程中的粗粒土破碎耗能。計算結果表明,常規三軸試驗條件下粗粒土破碎耗能主要受固結應力、土體摩擦系數M等因素的影響。