摘要
基于分子动力学模拟方法,建立了硫酸钙晶须(calcium sulfate whisker,CSW)改性沥青模型,研究了温度、拉伸力对表面改性前后硫酸钙晶须与沥青界面拉伸应力-位移曲线的影响。探讨了硫酸钙晶须-沥青界面的拉伸破坏形式和黏附机理,提出了一种可用于宏观分析的内聚力模型。分析结果表明:表面改性硫酸钙晶须(modified calcium sulfate whisker,MCSW)-沥青体系的应力峰值大于CSW-沥青体系;温度越高,晶须与沥青的应力峰值越低;拉伸力较大时,晶须与沥青破坏模式以黏附破坏为主;拉伸力较小时,晶须与沥青体系主要表现为黏聚破坏,改性沥青的拉伸应力在达到界面拉伸应力峰值前保持良好的力学性能,且变形可逆;当拉伸应力达到应力峰值后,界面体系的损伤不可逆;说明沥青与MCSW的界面强度更高,即改性沥青的界面力学性能更加优异。
Based on the molecular dynamics simulation method,a modified asphalt model of calcium sulfate whisker(CSW)was developed.The effects of temperature and tensile force on the tensile stress-displacement curves between asphalt and calcium sulfate whisker before and after surface treatment were investigated.In addition,the tensile failure and adhesion mechanism of the calcium sulfate whisker-asphalt interface were explored,and a cohesion model that can be used for macroscopic analysis was proposed.The analysis results indicate that the stress peaks of surface modified calci-um sulfate whisker(MCSW)-asphalt are greater than those of CSW-asphalt.The higher the temperature,the lower the peak stress of whisker-asphalt.When the tensile force is large,the damage mode of whisker-asphalt is mainly adhesion damage.When the tensile strength is low,the whisker-asphalt system mostly shows cohesive damage,the tensile stress of mod-ified asphalt maintains good mechanical performance before reaching the peak tensile stress of the interface,and the deforma-tion is reversible.When the tensile stress gets the peak stress,the damage to the interface system is irreversible.Therefore,the interfacial strength between asphalt and MCSW is higher,that is,the interfacial mechanical properties of modified as-phalt are better.
作者
赵辉
ZHAO Hui(Center for Pingdingshan Highway Development Center,Pingdingshan 467001,China)
出处
《现代交通技术》
2023年第5期18-24,共7页
Modern Transportation Technology
基金
国家重点研发计划(2021YFF0501003)
国家自然科学基金项目(52078233,51838006)。
关键词
硫酸钙晶须-沥青界面
拉伸作用
内聚力模型
黏附机理
分子动力学
calcium sulfate whisker-asphalt interface
tensile action
cohesion model
adhesion mechanism
molecular dy-namics
