桥面铺装不同防水黏层的工程适用性

The applicability of different waterproof adhesive interlayer for bridge deck pavement

桥面铺装防水黏层易发生水平层间渗水和积水等现象,进而造成层间黏结性能降低.通过电子计算机断层扫描、黏层水平渗水试验、层间剪切及拉拔试验,对工程中常用的5种桥面黏层(改性乳化沥青、4.75同步碎石、9.5同步碎石、5 mm沥青混凝土(5 mm asphalt concrete,AC-5)和稀浆封层)的工程适用性进行研究.基于数字图像处理技术,量化层间空隙分布状态,并分析各防水黏层孔隙分布特性与抗渗水、黏结性能的关系.研究结果表明,黏层的空隙分布状况与其渗水、积水及黏结特性紧密相关,层间空隙越丰富,越易渗水,黏层的黏结性能越低.在5种典型黏层中,AC-5的力学性能最优,改性乳化沥青的防水效果最佳.

Waterproof adhesive interlayer of the bridge deck pavement is prone to horizontal interlayer water seepage and ponding,which results in the degradation of interlayer bonding performance.In this paper,the CT scanning techniques,interlayer permeability tests,shear tests and pullout tests are used to comprehensively analyze the engineering applicability of five kinds of waterproof adhesive interlayer(modified emulsified asphalt,4.75 synchronous surface dressing,9.5 synchronous surface dressing,5 mm asphalt concrete(AC-5)and slurry seal)commonly used in engineering.Based on the digital image processing technology,we quantize the interlayer pore distribution and analyze the relationship between the pore distribution characteristics of each waterproof adhesive layer and its impermeability or bond performance.The results show that the distribution of pores in the waterproof adhesive interlayer is closely related to the seepage,water accumulation and bonding properties.The more the pores are,the easier it is for water to seepage through interlayer,the lower the bonding performance of the bonding layer.Among the five typical waterproof adhesive interlayers,AC-5 has the best mechanical properties,while the modified emulsified asphalt has the best waterproof effect.