聚氨酯泡沫体与道砟黏接性能的影响因素  

Influencing Factors of Adhesive Properties between Polyurethane Foam and Ballast for Stabilized Ballast Bed

作　　者：李书明[1,2] 程冠之 董全霄[1,2] 郑新国 谢永江[1,2] LI Shuming;CHENG Guanzhi;DONG Quanxiao;ZHENG Xinguo;XIE Yongjiang(Railway Engineering Research Institute,China Academy of Railway Sciences,Beijing 100081,China;State Key Laboratory of High Speed Railway Track Technology,Beijing 100081,China)

机构地区：[1]中国铁道科学研究院铁道建筑研究所,北京100081 [2]高速铁路轨道技术国家重点实验室,北京100081

出　　处：《建筑材料学报》2018年第6期926-932,共7页Journal of Building Materials

基　　金：中国铁道科学研究院科研基金项目(2016YJ047;2016YJ024;2016YJ034);中国铁路总公司科技研究开发计划课题(2017G002-C;2017G002-D);高性能土木工程材料国家重点实验室开放基金项目(2014CEM011)

摘　　要：研究了原材料R值(双组分原材料间异氰酸酯基(—NCO)与羟基(—OH)的摩尔比)、外加水量(wwater)和环境湿度(RH)对固化道床用聚氨酯(PU)泡沫体与道砟界面黏接性能的影响,并采用傅里叶变换衰减全反射红外光谱(ATR-FTIR)和扫描电镜(SEM)对PU泡沫体的组成和形态进行了表征.结果表明:随着原材料R值的增加,PU泡沫体与道砟之间的黏接强度逐渐增大,当原材料R值大于1.05时,试件黏接破坏形式为内聚破坏;外加水量越少,PU泡沫体密度越大,试件黏接性能越好,当外加水量小于0.45%时,试件的黏接破坏形式为内聚破坏;环境湿度会影响道砟表面干燥状态,进而影响试件黏接效果,当环境湿度不超过80%时,该值对试件黏接性能影响不明显.综合考虑PU泡沫体黏接性能和变形能力等因素,R值取1.05～1.20较合适,宜通过调整外加水量将PU泡沫体密度控制在160kg/m^3以上,实际施工环境湿度宜在80%以内.The effects of R value,water content(w water)and ambient humidity(RH)on the interfacial bonding strength between polyurethane(PU)foam and ballast were studied.The composition and morphology of PU foam were characterized by ATR-FTIR and SEM.The results show that the bonding strength between the foam and the ballast increases with the increase of the R value.When the R value is more than 1.05,the bonding failure mode is cohesion failure.The foam density increases with less water content,showing better bonding strength.When the water content is less than 0.45%,the bonding failure mode is always the cohesion failure.Ambient humidity will affect the surface dryness of the ballast,thus affecting the bonding performance.There is no obvious change for the bonding performance when the ambient humidity does not exceed 80%.Taking into account the foam adhesive properties and deformation capacity,R value with the range of 1.05 1.20 is appropriate,and the water content should be adjusted to control the foam with the density at 160 kg/m 3 or more.Moreover,the ambient humidity for actual construction environment should be less than 80%.

关 键 词：高分子材料 固化道床 聚氨酯 道砟 黏接性能 

分 类 号：U214.2[交通运输工程—道路与铁道工程] TQ328.3[化学工程—合成树脂塑料工业]