浇筑式钢桥面铺装层推挤变形病害机理分析
2016-07-11山宏宇李倩秘林源叶青贾晓阳
山宏宇 李倩 秘林源 叶青 贾晓阳



摘要:以贵州省北盘江大桥钢桥面铺装层推挤变形病害为研究背景,采用凝胶渗透色谱法(GPC)和傅里叶变换红外光谱法(FTIR),从沥青分子尺度分析钢桥面铺装产生推挤变形的原因。分析结果表明:沥青老化并不是造成钢桥面铺装层推挤变形的主要原因;从现场调查可知,第2层粘层粘结能力的降低是造成钢桥面铺装层推挤变形病害的次要原因;通过级配分析发现,造成钢桥面铺装层推挤变形的主要原因是浇筑式沥青混合料(GA)级配偏细以及GA中集料颗粒的棱角性较差所致。
关键词:钢桥面铺装;变形病害;凝胶渗透色谱法;红外光谱法;级配分析
中图分类号:U448.36
文献标志码:A 文章编号:1674-4764(2016)03-0104-06
Abstract:To better understand the failure mechanism of shoving on steel bridge deck overlay and guide the maintenance actions, an investigation was conducted on the performance of Beipanjiang bridge in terms of pavement shoving in Guizhou province. The Gel permeation chromatography (GPC) and Fourier Transfer Infrared (FTIR) spectrum were employed to analyze the failure mechanism of shoving from the point of molecular scale. The results showed that the asphalt aging is not the main cause for resulting in the formation of shoving disease on steel bridge deck. In addition, the reduction of adhesive strength of the second tack coat is a secondary cause for shoving disease of the steel bridge deck from the field survey research. Further, sieve analysis was performed to investigate the shoving mechanism on steel bridge deck with Gussasphalt (GA) mixture, and the results indicated that shoving failure is due to the gradation of GA mixture and poor angularity of aggregate particle rather than aging of asphalt binder.
Keywords:Steel bridge deck; Permanent deformation; Gel permeation chromatography; Fourier transfer infrared spectrum; sieve analysis
钢桥面铺装层是保护钢桥面板的重要层次,其设计、建设、养护、维修等技术已成为钢桥面铺装技术研究的重要内容[1-5]。从中国目前的大跨径钢桥面沥青铺装使用情况看,总体情况良好,但局部地区的一些钢桥表面沥青铺装层发生了较为严重的病害,这大大降低钢桥面铺装的服务水平,同时也对钢板防锈蚀产生不利影响。由于钢桥面的特殊性,一旦在钢桥面铺装层出现病害,会造成养护、维修的不便,同时,对道路交通会造成巨大影响,并产生行车安全隐患[5-7]。
目前,中国钢桥面沥青铺装层的常见病害类型有:裂缝类、变形类、表面损害类与桥接缝损害类。除了与传统沥青路面相似机理的典型病害,钢桥面铺装病害具有其特殊性,层间滑移与推挤是钢桥面沥青铺装层的典型病害之一。……
