Continuous welded rails (CWR) are track segments welded together to form a continuous miles-long track. With respect to mechanically-jointed rails, CWR are stronger, smoother, require less maintenance, and can be traveled at higher speeds. Despite these advantages, CWR are prone to fracture during cold seasons and to instability during warm seasons when the increase in the steel temperature induces extreme compression. To better understand buckling mechanism, engineers studied the structural behavior of rails under static and dynamic loads. Some of these models represent the basis of noninvasive methods to measure longitudinal stress. Both structural analyses and nondestructive evaluation methods are tools to predict the temperatures and the field conditions at which rails experience extreme tensile or compressive stress.

This article reviews the last three decades of research and development on the structural analysis and nondestructive evaluation of CWR. The scope of this document is to provide a holistic view of the developments in rail engineering and nondestructive evaluation relevant to the problem of thermal buckling. Advantages and limitations of the analyses and of the nondestructive methods are discussed based upon the information available in the scientific literature. Additionally, any knowledge gap to be addressed by the scientific community in the years to come is identified and discussed.

连续焊接导轨（CWR）是焊接在一起的轨道段，以形成连续的英里长的轨道。对于机械连接的导轨，CWR更坚固，更平滑，需要的维护更少，并且可以以更高的速度行驶。尽管有这些优点，但当钢水温度升高引起极高的压缩力时，CWR在寒冷季节容易破裂，在温暖季节却不稳定。为了更好地了解屈曲机理，工程师研究了钢轨在静态和动态载荷下的结构行为。这些模型中的一些代表了测量纵向应力的非侵入性方法的基础。结构分析和非破坏性评估方法都是预测钢轨承受极大拉应力或压应力的温度和现场条件的工具。

本文回顾了近三十年来对CWR的结构分析和无损评估的研究与开发。本文档的范围是对与热屈曲问题相关的铁路工程和无损评估的发展提供整体的看法。基于科学文献中可用的信息，讨论了分析方法和无损方法的优点和局限性。此外，确定并讨论了未来几年科学界需要解决的任何知识差距。