大跨径桥面UHPC-SMA界面粘结方案优化研究及其在丹江口水库特大桥工程中的应用

Research and application of interlayer bonding performance of UHPC-SMA pavement structure on bridge deck

针对UHPC-SMA桥面铺装沥青层与UHPC层易脱粘的特性,本文对UHPC-SMA结构层缩尺模型进行多次斜剪测试,研究了二阶反应环氧树脂粘层、环氧沥青粘层、高粘高弹改性沥青应力吸收层在不同预处理的UHPC表面的粘结性能和粘结特点。研究结果表明,刻槽和碎石嵌锁能有效提高UHPC-SMA组合结构粘结性能,但是大幅提高了环氧树脂和环氧沥青的涂刷量,不同构造深度抛丸处理对层间粘结影响较小。在抛丸处理的UHPC表面,环氧树脂抗剪切强度比环氧沥青和高粘高弹沥青分别高69.6%和154.4%,更适合于重载交通桥面;高粘高弹沥青多次剪切破坏后抗剪强度残留可高达29.6%,适合于交通量相对较低的桥面铺装。丹江口水库桥采用抛丸打毛至构造深度0.5mm+二阶反应环氧树脂粘结工艺,作为UHPC-SMA层间粘结方案,进行了成功的工程应用。

In response to the issue of debonding between the asphalt layer and the UHPC layer in UHPC-SMA bridge deck pavement,this study conducted multiple inclined shear tests on reduced-scale models of the UHPC-SMA structural layer.The adhesive properties and bonding characteristics of second-order reaction epoxy resin adhesive layer,second-order reaction epoxy asphalt adhesive layer,and high-viscosity high-elastic modified asphalt stress-absorbing layer on UHPC surfaces with different pretreatments were investigated.The research results showed that grooving and stone embedding can effectively improve the bonding performance of the UHPC-SMA composite structure,but significantly increased the application amount of epoxy resin and epoxy asphalt.Different construction depths of shot peening treatment had a minor influence on interlayer bonding.On the shot-peened UHPC surface,the shear strength of the epoxy resin was 69.6%higher than that of the epoxy asphalt and 154.4%higher than that of the high-viscosity high-elastic asphalt,making it more suitable for heavily loaded traffic bridge decks.The shear strength residual of the high-viscosity high-elastic asphalt after multiple shear failures could reach up to 29.6%,making it suitable for bridge deck pavement with relatively low traffic volume.The Danjiangkou Reservoir Bridge successfully applied the shot peening treatment to a construction depth of 0.5 mm+second-order epoxy resin bonding process as the interlayer bonding scheme for UHPC-SMA.