高性能水泥基复合材料梁疲劳性能的研究进展

Study Progress of Fatigue Behavior of High Performance Cement-based Composite Beam

具有应变硬化和多裂缝扩展特性的水泥基复合材料,适用于承受疲劳和冲击等动载的工程领域,有利于提高结构的基本力学性能、疲劳寿命和耐久性。高性能混凝土、高性能水泥基复合材料是建设长寿命桥梁结构的理想材料。为了合理使用高性能水泥基复合材料等新型材料,对高性能水泥基复合材料在桥梁工程和吊车梁中的应用状况、基本力学性能、疲劳特性试验研究和疲劳寿命预测模型等进行了梳理,重点关注了高性能混凝土、高性能水泥基复合材料组份及配合比设计、高性能水泥基复合材料在桥梁工程中的应用现状、混杂纤维高性能水泥基复合材料受弯构件的基本力学性能和疲劳破坏特征、高性能水泥基复合材料的疲劳破坏机制、疲劳寿命预测模型和疲劳设计方法等国际前沿问题的最新研究进展,分析了当前研究中存在的问题,展望了今后拟关注的研究重点。结果表明:今后拟开展的研究工作包括,需要在大量试验研究和理论分析的基础上,明确水泥基复合材料的疲劳损伤机理,建立具有物理基础的疲劳损伤演化模型,提出基于疲劳损伤本构模型的寿命预测方法,以丰富和发展仅仅基于试验的统计意义上的疲劳方程式和疲劳设计方法,为工程应用提供理论支持。

The cement-based composite materials with strain hardening and multi-crack propagation characteristics are suitable for the engineering field of bearing dynamic loads such as fatigue and impact,which is beneficial to improve the basic mechanical properties,fatigue life and durability of structures.Highperformance concrete and high-performance cement-based composites are ideal materials for long-life bridge construction.In order to use high-performance cement-based composites and other new materials reasonably,the application in bridge engineering and crane beam,the basic mechanical properties,the fatigue test study and the fatigue life prediction model of high performance cement-based composites are reviewed,focused on the latest study progress of advanced international issues such as high-performance concrete,composition and mix design of high-performance cement-based composites,application status of high-performance cementbased composites in bridge engineering,basic mechanical properties and fatigue failure characteristics of hybrid fiber high-performance cement-based composites in bending members,fatigue failure mechanism,fatigue life prediction model and fatigue design method of high-performance cement-based composites,etc.The existing problems in the current study are analyzed,and the future study focus is prospected.The result shows that the studies to be carried out in the future includes:on the basis of a large number of experimental research and theoretical analysis,clarify the fatigue damage mechanism of cement-based composites,establish the fatigue damage evolution model,and propose the life prediction method based on the fatigue damage constitutive model,so as to enrich and develop the fatigue equation and fatigue design method in the statistical sense based on test,and provide theoretical support for engineering application.