细粒土体及加载速率对土石混合体力学行为的影响

Influence of fine-grained soil and loading rate on the mechanical behavior of soil rock mixtures

土石混合体在工程中广泛应用于填筑和路基等领域,其力学行为对工程结构的稳定性和安全性具有重要影响。文章通过对含石量相似但细粒土为非黏性和黏性2种不同材料的试样,采用室内三轴试验开展相关研究,研究细粒土特性及试验加载速率对土石混合体力学行为的影响。结果表明:(1)在排水条件下,细粒土体为非黏性的试样展现出较高的强度特征,而在不排水条件下,细粒土体为黏性的试样则表现出更高的强度,这一发现凸显了细粒土特性在不同排水条件下对土石混合体强度的重要影响;(2)加载速率变化对土石混合体力学行为的显著影响,较快的加载速率导致内部块石颗粒更剧烈的运动、旋转和更频繁的破坏,从而影响了土石混合体的宏观力学特性。研究成果可为土石混合体工程的设计和施工提供参考。

Soil-rock mixtures are widely used in engineering for filling and subgrade applications,with their mechanical behavior playing a critical role in the stability and safety of engineering structures.This study utilized two types of fine-grained soils,non-cohesive and cohesive,to construct the soil-rock mixtures with similar stone content;indoor triaxial tests were conducted to investigate the effects of fine-grained soil type and loading rate on the mechanical behavior of soil-rock mixtures.The results show that under drained conditions,the strength of the soil-rock mixture containing non-cohesive soil is higher than that of cohesive soil,while under undrained conditions,the strength of the soil-rock mixture containing cohesive soil is higher.Variations in loading rate significantly impacted the mechanical behavior of soil-rock mixtures,with faster loading rates causing more intense movement,rotation,and frequent damage to internal stone particles,ultimately influencing their macroscopic mechanical properties.This study provides valuable insights for the design and construction of soil-rock mixture engineering.