严寒区高拱坝迎水面保温模板接缝止水试验研究

Thermal insulation formwork for high arch dam facing water surface in cold area experimental study on joint water stop

摘要

针对高拱坝预制免拆模板接缝止水这一关键技术难题，通过进行止水胶条形式和聚脲涂层形式两种结构的止水试验，分析不同止水材料、止水结构形式以及施工工艺对混凝土预制构件拼装接缝止水性能的影响，试验表明采用聚脲涂层止水结构形式，外水压1.5 MPa时，接缝无渗漏；采用止水胶条止水结构，水压0.6 MPa时在局部涂层处产生内水压开裂渗水破坏，同时止水胶条接缝需满足4 MPa的持续顶压才具备以上止水效果。通过对比两种结构的止水性能、施工便捷性及对拼装设备需求的苛刻程度，推荐在高拱坝迎水面预制免拆模板接缝止水采用聚脲涂层止水结构形式。解决了高拱坝预制免拆模板接缝止水这一影响结构安全性和耐久性的关键难题，为提高预制构件拼装接缝的止水效果提供理论依据和实践参考。

Abstract

Aiming at the key technical problem of joint waterstop for prefabricated non-removable formwork of high arch dams, waterstop tests were conducted on two structural forms: waterstop rubber strips and polyurea coating. The influence of different waterstop materials, structural forms and construction techniques on the waterstop performance of the joint of prefabricated concrete components is analyzed. The test result show that when the external water pressure is 1.5 MPa, there is no leakage in the joint with the polyurea coating waterstop structure. When the water pressure is 0.6 MPa, the waterstop structure with rubber strips causes internal water pressure cracking and water leakage at the local coating. Meanwhile, the joint with rubber strips needs to be continuously pressed with 4 MPa to achieve the above waterstop effect. By comparing the waterstop performance, construction convenience and the strictness of requirements for assembly equipment of the two structures, it is recommended to adopt the polyurea coating waterstop structure for the joint waterstop of prefabricated non-removable formwork on the upstream face of high arch dams. This solves the key problem of joint waterstop of prefabricated non-removable formwork of high arch dams, which affects the structural safety and durability, and provides theoretical basis and practical reference for improving the waterstop effect of the joint of prefabricated components.

关键词

严寒区 / 高拱坝 / 迎水面 / 预制保温模板 / 接缝止水试验

Key words

severe cold region / high arch dam / upstream face / prefabricated thermal insulation formwork / joint water stop test

Author summay

赵连生(1978—), 男, 正高级工程师, 副总经理兼总工程师, 学士, 主要从事混凝土桥梁、轨枕、管片、住宅等装配式预制构件技术研究。E-mail: [e-mail]

基金资助

新疆水利科技项目(XSKT-2023-12)

新疆水发建设集团科研项目(QBT087/FY36)

新疆水发建设集团科研项目(QBT067/FY28)