高速列车运营条件下自密实混凝土（SCC）动态性能演化过程及疲劳损伤属性研究

The CRTSⅢ non-ballasted track, As one of the premium end equipment of "go abroad" , there was a lack of the systematic research on the dynamic performance evolution and fatigue damage properties, a theoretical and experimental study is carried out on the crack force issue and relationship between crack and fatigue load evolution of SCC parts, in this project. The distribution characteristics of original pores in SCC are studied by 3H-2000PM1 high performance specific surface and micro-pore analyzer. The Dynamic evolution process test of SCC and SCC composite specimens are carried out under fatigue loading by the MTS tester, and the cracking character model test is also carried out. Crack dynamic evolution process is continuously observed by three integrated measurement system linked with real-time holographic interferometry, high-resolution digital camera and computer image processing system. Analyse the pore collapse effect of SCC parts at different loading periods, and research the generation and evolution of micro cracks, micro cavity damage，and leading to material properties evolution mechanism. Study on the Law of Energy variation in the process of SCC failure and its relationship with strength and overall failure by N-S Test Curve of SCC. Based on the theory of space-coupling dynamics of train-damage non-ballasted track and research CRTSⅢ non-ballasted track service status assessment methods. The research achievements provided reference for enriching and perfecting the theory on the concrete damages.

CRTSⅢ无砟轨道结构作为我国“走出去”的高端装备之一，目前对其结构部件的动态性能演化及疲劳损伤属性问题缺乏系统研究。本项目拟针对SCC部件的裂纹受力及其与疲劳荷载演化关系展开理论与试验研究。利用3H-2000PM1高性能比表面及微孔分析仪，研究SCC原始孔隙分布特征，通过MTS试验机模拟施加列车疲劳荷载，开展SCC及其复合试件动态演化过程及开裂性状等模型试验，利用实时全息干涉法、高分辨率数字摄像机与计算机图像处理系统相链接的三位一体化测量系统，连续观测裂纹动态演化过程。分析SCC部件在不同加载时间段的孔隙坍塌效应，研究微裂隙、微空洞的产生和演化导致材料性能嬗变机理。通过SCC的N-S曲线，研究SCC破坏过程中的能量变化规律及其与强度和整体破坏之间的联系，基于列车-损伤无砟轨道空间耦合动力学等理论，研究CRTSⅢ型无砟轨道服役状态评估方法。研究成果将为进一步丰富和完善混凝土伤损理论提供参。

本项目针对SCC部件的裂纹受力及其与疲劳荷载演化关系展开理论与试验研究。利用3H-2000PM1高性能比表面及微孔分析仪，研究高性能SCC孔隙分布特征，通过MTS试验机模拟施加列车疲劳荷载，开展高性能SCC及其复合试件动态演化过程及开裂性状等模型试验，利用实时全息干涉法、高分辨率数字摄像机与计算机图像处理系统相链接的三位一体化测量系统，连续观测裂纹动态演化过程。研究高兴SCC部件在不同加载时间段的孔隙坍塌效应，裂纹贯通效应，研究微裂隙、微空洞的产生和演化导致材料性能嬗变机理。通过SCC的N-S曲线，研究SCC破坏过程中的能量变化规律及其与强度和整体破坏之间的联系，基于列车-损伤无砟轨道空间耦合动力学等理论，研究CRTSⅢ型无砟轨道服役状态评估方法。研究成果将为进一步丰富和完善混凝土伤损理论提供参。