国内外预应力混凝土轨枕纵裂伤损研究综述

Research Summary of Longitudinal Crack Damage of Prestressed Concrete Sleepers at Home and Abroad

预应力混凝土轨枕作为铁路轨道中重要的部件,目前总体使用效果良好,但也存在不同类型的伤损,其中以纵裂伤损最为突出。本文分析确定了预应力轨枕纵裂伤损的主要特征,归纳了铁路线路中出现的6种纵裂伤损类型,调研和总结了国内外预应力混凝土轨枕纵裂伤损的研究现状及预防措施。结果表明,纵裂伤损的两大主要原因是轨枕结构受力不合理和材料性能劣化,最常见的影响因素是轨枕的预应力过大和混凝土材料的碱骨料反应。此外,轨枕使用的环境条件、后期线路状态、列车疲劳动荷载对轨枕纵裂伤损的发生和发展具有一定的影响。建议轨枕设计时,应在保证承载强度的前提下合理设计轨枕预应力,并配置一定的箍筋;在轨枕生产过程中,应确保原材料的性能以及生产工艺都满足相应规范的要求。

As an important part of railway track,prestressed concrete sleepers have good overall use effect,but there are also different types of damage,of which longitudinal crack damage is the most prominent.This paper analyzed and determined the main characteristics of longitudinal crack damage of prestressed concrete sleepers,summarized six types of longitudinal crack damage in railway lines,and surveyed and summarized the research status and preventive measures of longitudinal crack damage of prestressed concrete sleepers at home and abroad.The results show that the two main causes of longitudinal crack damage are the unreasonable stress of the sleeper structure and the deterioration of the material properties.The most common influencing factors are the excessive prestress of the sleeper and the alkaliaggregate reaction of the concrete material.In addition,the environmental conditions for the use of sleepers,the later line status,and the train fatigue dynamic load have a certain impact on the occurrence and development of longitudinal crack damage of sleepers.It is suggested that the sleeper prestress should be reasonably designed and equipped with certain stirrups on the premise of ensuring the bearing strength during the sleeper design.During the production of sleepers,the performance of raw materials and production process should meet the requirements of corresponding specifications.