沉管隧道沥青路面服役现状及病害分析

为解决我国沉管隧道沥青路面实践经验缺乏等问题，以文献查阅、交流问询、实地观察和现场检测相结合的方式，对港珠澳大桥海底隧道、韩国釜山海底隧道等国内外12座沉管隧道沥青路面服役现状进行调研，对病害原因进行分析。结果表明： 1）沉管隧道沥青路面车辙病害并不突出，路面最低温度比区域自然环境最低气温高约6 ℃，最高温度与区域自然环境最高气温相当，服役温度通常不超过40 ℃； 2）裂缝是沉管隧道沥青路面最为典型的病害之一，沉管隧道管节和节段接缝处是沥青路面受力的薄弱环节，易开裂破损； 3）存在路面平整度较差、抗滑性能衰减突出、隧道口易形成坑槽病害等问题； 4）对于新建沉管隧道，宜根据隧道结构条件、环境条件和交通条件进行力学分析，对节段和管节接缝处沥青路面进行细部设计； 5）对于沉管隧道上面层沥青混合料，宜采用较大公称粒径的SMA以及耐磨性能更优的集料； 6）对于隧道口上面层沥青混合料，应具有良好的抗水侵害能力。

Service Status and Disease Analysis of Asphalt Pavement of Immersed Tunnel

There is little practical experience of asphalt pavement in immersed tunnel in China. As a result, the service status of asphalt pavement of 12 immersed tunnels in China and abroad, such as Hong Kong Zhuhai Macao Bridge Subsea Tunnel and Busan Subsea Tunnel in South Korea, etc.KG-*3], are investigated, and the causes for diseases are analyzed based on literature review, communication and enquiry, on site observation and on site test. The results show that: (1) The rut diseases of the asphalt pavement of immersed tunnels are not prominent, the minimum temperature of the road surface is about 6 ℃ higher than that of the natural environment in the project area, the maximum temperature is close to that of the natural environment, and the service temperature usually does not exceed 40 ℃. (2) Cracks are one of the most typical diseases of the asphalt pavement of immersed tunnels, and the segment joints of immersed tunnel are weak links on the asphalt pavement, where crack and damage often occur. (3) In addition, the asphalt pavement of immersed tunnels has other diseases, such as poor roughness, obvious attenuation of skid resistance, and easy formation of pothole diseases at tunnel entrance. (4) For newly built immersed tunnel, mechanical analysis should be carried out according to the tunnel structural conditions, environmental conditions and traffic conditions, and detailed design for the asphalt pavement at segment joints should be carried out further. (5) The SMA with larger NMPS and aggregate with better wear resisting performance are suggested to use for the asphalt material. (6) The asphalt on the upper layer of tunnel entrance should be characterized by good water resistance.