伸缩缝防渗结构聚脲基涂层剥离破坏研究

发布时间：2018-05-20 10:17

本文选题：内聚力 + 有限元　；参考：《水利学报》2017年01期

【摘要】：水工建筑物普遍存在伸缩缝渗漏破坏问题,其破坏机理亟待研究。本文基于南水北调工程实际背景,引入损伤断裂力学理论,建立了内聚力单元的有限元仿真模型,并根据防渗涂层剥离试验的反向压力-位移变形数据,给出了适合于聚脲基复合防渗体系黏接层内聚力单元的刚度和黏聚系数等参数。计算了剥离反向压力,分析了聚脲基防渗涂层厚度对剥离临界反向压力的影响,以及水压力和伸缩缝扩展位移工况下,涂层厚度、涂层弹性模量和内聚力单元切向黏接强度对涂层剥离破坏长度的影响。数值计算结果表明,剥离反向压力与剥离试验的结果基本一致,说明内聚力模型参数的合理,能够有效模拟聚脲基复合防渗涂层剥离破坏的力学机理。同时,水压力和伸缩缝扩展位移工况下的分析结果,也说明了建立的聚脲基防渗涂层破坏分析方法对伸缩缝的防渗设计具有定量的指导作用。
[Abstract]:The leakage failure of expansion joints is a common problem in hydraulic structures, and its failure mechanism needs to be studied urgently. Based on the practical background of South-to-North Water transfer Project and introducing the theory of damage and fracture mechanics, the finite element simulation model of cohesive force element is established in this paper, and based on the reverse pressure-displacement deformation data of anti-seepage coating peeling test, The parameters such as stiffness and cohesion coefficient of adhesive layer for polyurethane-based composite impervious system are given. The reverse peeling pressure was calculated, and the influence of the thickness of polyurethane-based impervious coating on the critical reverse pressure of peeling was analyzed, and the coating thickness was also analyzed under the condition of water pressure and expansion displacement of expansion joint. The influence of elastic modulus and cohesive force unit tangential bonding strength on the delamination failure length of the coating. The numerical results show that the reverse peeling pressure is basically consistent with that of the peeling test, which indicates that the cohesive force model parameters are reasonable and can effectively simulate the mechanical mechanism of the peeling failure of polyurethane-based composite impervious coatings. At the same time, the analysis results under the condition of water pressure and expansion displacement of expansion joint also show that the failure analysis method of polyurethane-based impervious coating has a quantitative guiding effect on the impermeability design of expansion joint.
【作者单位】：中国水利水电科学研究院结构材料研究所;北京化工大学理学院;曼彻斯特大学数学系;
【分类号】：TV543

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