防水层对富水隧道复合式路面结构孔隙水压力的影响及对策研究

Pore-water Pressure Impact Assessment of Waterproof Layer in Water-rich Tunnel Composite Pavement

基于土力学流固耦合计算理论,采用ABAQUS大型分析软件,建立了富水隧道复合式路面三维有限元等效模型,分析了不同防水层方案路面结构在车辆荷载作用下的孔隙水压力变化规律,结果表明:当路面结构处于全厚度均受到水入渗时,防水层设置层位对孔隙水压力的影响几乎可以忽略不计,为有效发挥防水层减少孔隙水压力的作用,路面结构上部宜从路表便开始阻止水的入渗的"早防水"、下部结构则宜采取尽早(调平层)铺设防水层的"深防水"策略。最后结合工程实践经验,从密实性面层、改性沥青碎石封层、调平层顶面防水、隧道仰拱防水等方面提出了富水隧道复合式路面的防水层设置对策。

Base on the theory of soil mechanics of fluid-solid coupling,a three-dimensional water- rich tunnel pavement was established by ABAQUS software. The pavement pore-water pressure variations with different waterproof layer settings were analyzed, results indicate that, the vertical position of water- proof have little impact when the pavement was full of water in the whole depth. In order to assure preven- ting water as much as possible, the pavement should prevent water on the surface layer and in the bottom layer as soon as possible. At last,engineering measures of water-proof layer setting were put forward eom- bined with engineering practice,such as dense surface layer, modified asphalt macadam seal coat layer, leveling layer water-proof,tunnel inverted arch and so on.