考虑颗粒破碎效应的钙质砂亚塑性本构模型OA

[Purposes]The particles of calcareous sand are prone to breakage during the force application process.This characteristic significantly affects the macroscopic mechanical behavior of the material.Delving into the mechanism of how particle breakage influences the mechanical properties of calcareous sand is of great significance for practical applications in geotechnical engineering.[Methods]The extent of particle breakage was quantified utilizing a plastic work function per unit volume.The concept of the limit distribution of void ratios was introduced,enabling the derivation of an evolution equation for the void ratio that incorporated particle breakage.A theoretical framework for the critical state line,dynamically coupled with the relative breakage index,was subsequently developed.[Results]The numerical simulation results of the system are compared and analyzed with the test results under different confining pressures and drainage conditions,thereby verifying the rationality and applicability of the established model.Particle breakage during loading markedly diminishes the strength characteristics of the granular material,including both peak strength and critical state strength;an increase in the initial confining pressure exacerbates the degree of particle breakage.In comparison to the original hypoplastic model,the enhanced model demonstrates superior predictive capability for both peak and critical state mechanical behavior.[Conclusions]This study elucidates the intrinsic mechanism through which particle breakage governs the strength characteristics of calcareous sand from the perspectives of plastic work per unit volume and critical state theory.