【作者】 李扬；

【导师】 钟燕辉； 汪自力；

【作者基本信息】 郑州大学 ， 工程硕士（专业学位）， 2021， 硕士

【摘要】 随着我国经济的快速发展,我国在边远冻土区的公路、铁路等交通基础设施的建设也越来也多,近年来随着全球气候转暖,使得冻土区地基条件更加严酷,加剧了冻土路基路面的破坏程度。高聚物注浆修复技术是道路病害修复与养护的重要手段,然而面临冻土区特殊的工程环境,传统高聚物注浆材料已经不能满足需求,低放热高聚物注浆材料在冻土区道路病害的修复和养护中发挥着不可替代的作用,但其在频繁荷载作用的使用性能还不可知,本文基于以上背景,主要以应用于冻土区道路病害修复的低放热高聚物注浆材料为研究对象,采用室内试验的方法研究了低放热高聚物注浆材料在抗压情况下和抗弯情况下疲劳性能,并估算了低放热高聚物注浆材料的疲劳寿命,分析了影响低放热高聚物注浆材料疲劳性能的因素以及微观结构特点,旨在为低放热高聚物注浆材料在冻土区的应用提供理论依据及参考,本文主要研究内容及成果如下:(1)研究了低放热聚氨酯高聚物注浆材料的抗压强度以及抗压疲劳性能,包括研究在压缩过程中应力应变关系、不同密度的低放热高聚物试件在同一应力水平循环压缩作用下的应变-循环次数关系、同种密度的低放热高聚物试件在不同应力水平循环压缩作用下的应变-循环次数关系。(2)研究了低放热聚氨酯高聚物注浆材料的抗弯强度以及抗弯疲劳性能,包括研究试件在弯曲过程中荷载位移关系、不同密度的低放热高聚物试件在同一应力水平循环弯曲作用下的位移-循环次数关系、同种密度的低放热高聚物试件在不同应力水平下循环弯曲作用下的位移-循环次数关系。(3)从宏观的疲劳试验现象,分析并归纳了低放热聚氨酯高聚物注浆材料的疲劳破坏形式,从微观电镜扫描试验,分析总结了低放热高聚物注浆材料各种破坏形式在微观下的疲劳损伤机理。更多还原

【Abstract】 With the rapid development of China’s economy,the construction of highway,railway and other transportation infrastructure in remote frozen soil areas is also increasing.In recent years,with the global climate warming,the foundation conditions in frozen soil areas are more severe,and the damage degree of frozen soil subgrade and pavement is aggravated.High polymer grouting technology is an important means of road disease repair and maintenance.However,in the face of special engineering environment in frozen soil area,traditional polymer grouting materials can no longer meet the demand.Low exothermic polymer grouting materials play an irreplaceable role in the repair and maintenance of road diseases in frozen soil area,but their performance in frequent loading is unknown.Based on the above background,this paper studies the fatigue properties of low exothermic polymer grouting materials used in road disease repair in frozen soil area by indoor test,The fatigue life of low exothermic polymer grouting materials is estimated,and the factors affecting the fatigue properties and microstructure of low exothermic polymer grouting materials are analyzed.The purpose of this paper is to provide theoretical basis and reference for the application of low exothermic polymer grouting materials in frozen soil.The main research contents and results are as follows :(1)the compressive properties of low exothermic polyurethane polymer grouting materials and the fatigue properties under compressive loading are studied,It includes the relationship of stress and strain,the relationship of strain cycle times of low exothermic polymer specimens with different density under the same stress level compressive loading,and the relationship of strain cycle times of low exothermic polymer specimens with the same density under different stress level compressive loading.(2)The anti-bending properties of low-heat polyurethane polymer grouting materials and fatigue properties under bending conditions were studied,including the load-displacement relationship during bending,the displacement cycle times of low-heat polymer specimens with different densities in the same stress level cycle,and the displacement cycle times of low-heat polymer specimens with the same density in different stress level cycle.(3)From the macroscopic fatigue test phenomenon,the fatigue failure forms of low exothermic polyurethane polymer grouting materials under compression and bending are analyzed and summarized.更多还原