粉煤灰路基的力学变形特性及综合含水率研究  

Mechanical Deformation Characteristics and Comprehensive Water Content of Fly Ash Subgrade

作　　者：郑立阳 惠迎新[1,2,3] 郭聚坤 闫升 董旭光 ZHENG Liyang;HUI Yingxin;GUO Jukun;YAN Sheng;DONG Xuguang(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China;Ningxia Communications Construction Co.,Ltd.,Yinchuan 750021,China;Ningxia Solid Waste Resources Road Comprehensive Utilization Technology Engineering Research Center,Yinchuan 750021,China;Department of Highway and Architecture,Shandong Transport Vocational College,Weifang 261206,China)

机构地区：[1]宁夏大学土木与水利工程学院,银川750021 [2]宁夏交通建设股份有限公司,银川750021 [3]宁夏固废资源道路化综合利用技术工程研究中心,银川750021 [4]山东交通职业学院公路与建筑系,潍坊261206

出　　处：《硅酸盐通报》2025年第4期1486-1494,1524,共10页Bulletin of the Chinese Ceramic Society

基　　金：宁夏回族自治区重点研发计划重点项目(2022BFE02006)。

摘　　要：合理确定施工含水率对确保路基填料达到最佳综合性能具有重要意义。为探究含水率对粉煤灰路基强度变形特性的影响规律,确定适合粉煤灰路基施工含水率,以宁夏地区粉煤灰为试验材料,结合击实试验结果,开展固结压缩和剪切等室内试验,分析不同含水率下粉煤灰的力学特性,确定各单一因素下的最佳含水率,并基于灰色关联法提出能够保证粉煤灰路基达到最佳综合性能的施工含水率。结果表明,随含水率增加,压缩系数先减小后增大,压缩模量先增大后减小,最终竖向应变在一定范围内波动,含水率为31%时粉煤灰压缩性最小。在高法向应力和高含水率时粉煤灰剪切应力-剪切位移曲线表现为强应变软化型。随着含水率增加,残余内摩擦角逐渐减小,残余黏聚力先增加后减小并趋于稳定,含水率为23%时粉煤灰残余抗剪强度最大。含水率在31%~35%时,各力学指标关联度值维持在一个较高且相对稳定的区间,可作为指导施工的综合含水率。Reasonable determination of construction water content is of great significance to ensure the best comprehensive performance of subgrade filling.In order to investigate the influence of water content on the strength deformation characteristics of fly ash subgrade and determine the water content suitable for the construction of fly ash subgrade,the fly ash in Ningxia area was used as the test material.Combined with the results of compaction test,consolidation compression and shear were carried out to analyze the mechanical properties of fly ash under different water content,and the best water content under each single factor was determined.Based on the gray relational analysis,the construction water content of fly ash subgrade can be proposed to ensure the best comprehensive performance.The results show that with the increase of water content,the coefficient of compression decreases first and then increases,the modulus of compression increases first and then decreases,the final vertical strain fluctuates within a certain range,and the compressibility of fly ash is the smallest when the water content is 31%.At high normal stress and high water content,the shear stress-shear displacement curve of fly ash shows strong strain softening type.With the increase of water content,the residual internal friction angle decreases,the residual cohesion increases and then decreases and tends to stabilize,and the residual shear strength of fly ash is the largest when the water content is 23%.When the water content in the range of 31%~35%of the mechanical index correlation degree value maintained in a high and relatively stable interval,which can be used as a guide to the construction of the comprehensive water content.

关 键 词：粉煤灰 压缩特性 剪切特性 残余抗剪强度指标 灰色关联法 综合含水率 

分 类 号：U416.11[交通运输工程—道路与铁道工程]