道路用煤矸石路基残余剪切特性与细观行为

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中图分类号：U414 文献标志码：A 文章编号：1008-0562（2026）01-0042-10

Residual shear characteristics and microscopic behavior of coal gangue subgrade for road use

ZHANG Shent， GUO Jukun2， HUI Yingxin134*， YAN Sheng³4， PAN Mingjiang§，6

（1.School of Civil and Hydraulic Engineering，Ningxia University， Yinchuan 75oo21，China;2.Schoolof

Highway and Architecture，Shandong Transport Vocational Colege，Weifang 261206，China;3.Ningxia Communications Construction Company Limited，Yinchuan 75ooo1， China;4.Ningxia Solid Waste Resource Roadization Application Center， Yinchuan 75oo04， China;5. Xinjiang Transportation

Construction Group Company Limited， Urumqi 83o016， China;6.Xinjiang Communications Construction Planning Survey and Design Institute Company Limited， Karamay 834o99， China）

Abstract： To explore the influence of water content and particle gradation on the evolution of residual shear strength characteristics ofcoal gangue subgrade filland reveal the underlying mechanisms，this study employed drained repeated direct shear tests to evaluate the mechanical responses ofcoal gangue under varying conditions. Aditionally， discrete element numerical simulations were conducted to analyze，from a mesoscopic perspective， the evolution characteristics of particle displacement fields and contact force chain networks during shearing.The results idicate thatthe shear stress-displacement curves ofcoal gangue exhibit strain-hardening behavior， which can be wellfited by a hyperbolic model. The residual shearstrength decreases significantly with increasing water content，accompanied bya reduction ininterparticle friction and interlocking eects.This trend is more pronounced in samples with higher fractal dimensions （well-graded）.At the mesoscopic level， specimens with lower fractal dimensions are dominated by a coarse-particle skeleton with highly concentrated force chains， whereas those with higher fractal dimensions show enhanced fine-particle filing，leading to a more uniform distribution of contacts and reduced shear stability.This study elucidates the macro-mesoscopic coupling mechanisms and provides an important theoretical basis for material design and long-term stability prediction of coal gangue subgrades.

Keywords：roadbed engineering；coal gangue；residual strength；particle size distribution；mechanical mechanism; fractal dimension;interlockingeffect

0引言

中国是全球最大的煤炭消费国，预计到2035年，煤炭需求量将占全球总需求量的 47% 。（剩余13731字）