钢桥面环氧沥青防水粘结层耐久性影响分析

大量现场调查表明,因防水粘结层失效而造成的钢桥面铺装层脱层或滑移是造成钢桥面铺装病害的重要原因之一,交通荷载、温度、水等因素通常被认为是影响铺装防水粘结层长期使用的主要因素。根据钢桥面铺装特点与技术要求,选择环氧沥青作为防水粘结层进行试验研究。考虑两种温度(25℃、70℃)的拉拔试验和剪切试验,明确了防水粘结层的温度敏感性;选择不同表面构造钢板进行拉拔试验,考察其对环氧沥青防水粘结层粘结性能的影响;以高温浸水拉拔试验和剪切试验,评价了高温水对钢桥面铺装防水粘结层的影响;试验结果表明:随着温度的升高,防水粘结层的拉拔强度和抗剪强度下降很快;随着浸水时间的增加,拉拔和抗剪强度下降较慢,且抗剪强度基本不变。因此,采用环氧沥青作为钢桥面防水粘结层时,温度应作为首要考虑因素。

Durability Analysis of Epoxy Asphalt Waterproof Bonding Layer of Steel Bridge Deck

Many field surveys show that delaminating or slip off of the steel bridge deck pavement layer caused by failure of the waterproof layer is one of the important reasons which caused the steel deck plate paving failure.The traffic load,temperature and water factor are usually considered as the main factors that affect long-term pavement performance of the waterproof layer binding.Epoxy asphalt is selected to be tested according to the characteristic and technical requirement of steel deck bridge pavement Based on the drawing test and shear test in the two different temperatures of 25 ℃ and 70 ℃,the paper determines the temperature sensitivity of waterproof layer.In addition,the effects of high temperature water on waterproof bonding layer of steel bridge deck are evaluated through drawing and shear experiments in high temperature.Experiment result indicates that the drawing strength and shear strength of the waterproof bonding layer falls sharply with the increasing of the temperature;the drawing strength and shear strength decline slowly with the increasing of soaking time and the shear strength tends to be unchanged.The temperature should be considered as the first factor when adopting epoxy asphalt as waterproof bonding material of steel bridge.