界面键合对地聚合物-骨料性能影响的分子模拟

Molecular Simulation of Interface Bonding Effects on Properties of Geopolymer-Aggregate

界面键合方式是影响地聚合物与二氧化硅骨料界面特性的核心因素.通过分子动力学模拟,建立了3种界面键合方式的复合模型,并探究了其对界面结构及界面力学的影响.结果表明:界面化学键涵盖Si—O—Al键、Si—O—Si键及Na—O键;随着界面化学键浓度的增加,界面过渡区的宽度不变,密度增大,界面相互作用增强;界面处共价键贡献的能量是地聚合物与骨料结合的主要能量,共价键含量的增加显著增强了界面强度;当界面Si—O—Si键浓度超过地聚合物中的Si—O—Si键浓度时,界面不再是强度发展的限制因素.

The interface bonding method playing a pivotal role in influencing the interface characteristics between geopolymer and silica aggregate.Three distinct interface bonding models were established through molecular dynamics simulations to explore their impact on the interface structure and mechanical properties.The results reveal that the interface chemical bonds encompass Si—O—Al,Si—O—Si and Na—O bonds.Increasing the concentration of chemical bonds maintains a consistent interface transition zone width and enhances the density within the interface transition zone,reinforces interfacial interactions.The energy contributed by covalent bonds at the interface is the main energy for the combination of geopolymer and aggregate.Augmenting the content of covalent bonds at the interface significantly fortified interface strength.When the concentration of Si—O—Si bonds at the interface surpasses that within the geopolymer bulk,the interface ceases to be the primary factor limiting strength development.