军工路高架桥面防水黏结层关键技术研究

Research on Key Technology of Waterproof Bonding Layer of Elevated Bridge Decks in Jungong Road

摘要:

为突破钢混叠合梁超薄铺装体系中防水黏结层的技术瓶颈，以上海市军工路快速路高架桥工程为背景，针对“取消找平层+7 cm超薄铺装（3cm浇筑式沥青GA-10+4 cm SMA-13）”的创新型铺装结构，系统研究了该体系下防水黏结层的材料选型、施工工艺优化及性能验证。通过对比溶剂型沥青黏结剂、甲基丙烯酸甲酯树脂和热熔型改性环氧树脂的性能，选择热熔型改性环氧树脂作为核心材料，其25 ℃拉拔强度达1.5～2.0 MPa、60 ℃抗剪强度0.9～1.2 MPa、耐热性不低于200 ℃，兼具高耐水性（强度保持率85%~90%）与施工适应性。施工工艺通过精细化控制实现质量提升，施工前采用抛丸处理确保基面粗糙度0.5～1.0 mm；采用人工刮涂施工方式，每平方材料用量严格控制在0.55～0.6 kg。性能测试表明：全线拉拔强度平均值2.21～2.53 MPa（远超设计不小于1.5 MPa），合格率100%；25 ℃抗剪强度全线均值1.02 MPa，60 ℃高温下仍达0.78 MPa（超规范不小于0.5 MPa）；浸水7 d后强度保持率87.5%，80 ℃加速老化7 d后拉拔与抗剪强度保持率分别为86.3%和82.1%。研究表明，采用热熔型改性环氧树脂的施工工艺，可显著提升层间黏结强度与高温稳定性，解决超薄铺装体系层间脱空与水损害难题，为同类工程提供了材料选型标准、工艺控制方法及性能验证体系。

Abstract:

In order to overcome the technical bottleneck of the waterproof bonding layer in the ultra-thin paving system of steel-concrete composite beams, taking the Shanghai Jungong Road Expressway Elevated Bridge Project as the background, and focusing on the innovative paving structure of “canceling the leveling layer + 7 cm ultra-thin paving (3 cm poured asphalt GA-10 + 4cm SMA-13)”, the material selection, construction process optimization and performance verification of the waterproof bonding layer under this system are systematically studied. By comparing the properties of solvent based asphalt binder, methyl methacrylate resin and hot-melt modified epoxy resin, the hot-melt modified epoxy resin is selected as the core material. Its 25 ℃ tensile strength reaches 1.5~2.0 MPa, 60 ℃ shear strength is 0.9-1.2 MPa, heat resistance is not lower than 200 ℃, and it has high water resistance (strength retention rate of 85% -90%) and construction adaptability. The construction process achieves quality improvement through refined control. Before construction, the shot blasting treatment is used to ensure a roughness of 0.5~1.0 mm on the base surface. The manual scraping and coating construction method is adopted, and the material consumption per square meter is strictly controlled at 0.55~0.6 kg. The performance tests show that the average tensile strength of the entire line is 2.21~2.53 MPa (far exceeding the design not less than 1.5 MPa) with a pass rate of 100%. The average shear strength of the entire line at 25 ℃ is 1.02 MPa, and it still reaches 0.78 MPa at high temperature of 60 ℃ (exceeding the specification not less than 0.5 MPa). After 7 d of immersion, the strength retention rate is 87.5%, and after accelerated aging at 80 ℃ for 7 d, the tensile and shear strength retention rates are 86.3% and 82.1%, respectively. The research shows that the construction technology with the hot-melt modified epoxy resin can significantly improve the interlayer bonding strength and high-temperature stability, solve the problems of interlayer delamination and water damage in ultra-thin paving systems, and provide the material selection standards, process control methods and performance verification systems for similar projects.