公路隧道内壁接缝处弹性密封垫的防水失效机理研究

Research on the Waterproof Failure Mechanism of Elastic Gasket at Inner Wall Joint of Highway Tunnel

依托某公路隧道工程项目,通过有限元软件建立弹性密封垫与混凝土沟槽的数值模型。研究施加水压力后弹性密封垫的变形和受力特性,对不同水压力作用下的失效机理进行剖析,从而验证其合理性。结果表明:未施加水压力时,弹性密封垫接触应力沿中轴线呈对称分布,峰值出现在端部位置。由于水压力对密封垫的冲击,使得弹性密封垫出现了明显变形,主要表现在密封垫中间孔洞的缩小和左侧与沟槽间空间的增大。左侧孔洞明显变小,但仍上下对称。施加水压力后,施加水压力的一侧接触应力减小,接触应力非对称分布,总体呈现出左高右低的变化趋势,且接触应力大小变化趋势相较于无水压工况较为滞后。

Based on a highway tunnel project,this paper establishes a numerical model of elastic gasket and concrete groove through finite element software.The deformation and stress characteristics of the elastic gasket under applied water pressure were studied.The failure mechanisms under different water pressure conditions were analyzed to validate their rationality.The results showed that without applied water pressure,the contact stress of the elastic gasket along the central axis exhibited a symmetric distribution,with the peak appearing at the end positions.Due to the impact of water pressure on the sealing gasket,significant deformation occurred,manifested in the reduction of the central hole in the sealing gasket and an increase in the space between the left side and the groove.The left-side hole notably decreased in size but remained symmetrically aligned.After applying water pressure,the contact stress on the side with applied water pressure decreased,and the contact stress is distributed asymmetrically,showing an overall trend of higher stress on the left and lower stress on the right.The change trend of the contact stress size lags behind that of the working condition without water pressure.