A key issue in ensuring the stability of transportation infrastructure in permafrost regions of the Qinghai–Tibet Plateau (QTP) is to prevent the degradation of the underlying permafrost. Therefore, several cooling methods (such as sun sheds, duct-ventilated embankment, thermosyphon, crushed-rock embankment, and dry bridge) have been developed to stabilize the underlying permafrost and mitigate thaw settlement. In this study, considering climate warming and engineering geologic conditions, a necessity model of cooling methods for transportation infrastructure was proposed. The application features of cooling methods along the Qinghai–Tibet Railway (QTR) in permafrost regions were systematically and comprehensively summarized to validate the model accuracy. The results indicated that the model has satisfactory performance and can determine the necessity index (NI) of cooling methods in a certain area. Based on the NI values, convenient application criteria for cooling methods were proposed. Specifically, the transportation infrastructure can be constructed without cooling methods in regions where the NI is less than 1.088. The results indicated that approximately 97% of the regions (NI < 1.088) in the study area are located in talik and low-temperature and ice-poor permafrost regions. Therefore, NI = 1.088 was determined to be a reasonable boundary value for deciding whether to apply cooling methods. Finally, the reliability of the criteria was validated by analyzing the settlement data of six typical embankment sections. This model can improve the reasonableness of the decision-making process of cooling method selection during the design and construction of transportation infrastructure, not only in the Qinghai–Tibet engineering corridor but also in a wide region of the QTP.

确保青藏高原多年冻土区交通基础设施稳定的一个关键问题是防止下伏冻土退化。因此，已经开发了几种冷却方法（如阳光棚、管道通风路堤、热虹吸、碎石路堤和干桥）来稳定下伏永久冻土并减轻融化沉降。在本研究中，考虑到气候变暖和工程地质条件，提出了交通基础设施冷却方法的必要模型。系统综合总结了青藏铁路沿线冷却方法在多年冻土地区的应用特点，验证了模型的准确性。NI ) 的冷却方法在一定区域。基于NI值，提出了冷却方法的便利应用标准。具体而言，在NI小于 1.088 的地区，可以在没有冷却方法的情况下建造交通基础设施。结果表明， 研究区约97%的区域（NI < 1.088）位于塔里克和低温少冰的多年冻土区。因此，NI = 1.088 被确定为决定是否应用冷却方法的合理边界值。最后，通过对六个典型路堤断面沉降数据的分析，验证了该准则的可靠性。该模型不仅在青藏工程走廊，而且在青藏高原大片区域，都可以提高交通基础设施设计和建设过程中冷却方式选择决策过程的合理性。