寒区隧道围岩-喷层界面增黏与抗冻试验研究  

Experimental study on tackifying-frost resistance of tunnel surrounding rockspray interfaces in cold regions

作　　者：刘慧[1] 徐海南 任建喜[1] 申艳军 贾海梁[1] 奚家米[1] 唐丽云[1] 郁金捷 魏尧 LIU Hui;XU Hainan;REN Jianxi;SHEN Yanjun;JIA Hailiang;XI Jiami;TANG Liyun;YU Jinjie;WEI Yao(College of Architecture and Civil Engineering,Xi'an University of Science and Technology,Xi¢an,Shaanxi 710054,China;Department of Geological Engineering and Geomatics,Chang¢an University,Xi¢an,Shaanxi 710054,China;State Key Laboratory of Loess Science,Chang¢an University,Xi¢an,Shaanxi 710054,China;State Key Laboratory of Road Engineering Safety and Health in Cold and High-Altitude Regions,CCCC First Highway Consultants Co.Ltd.,Xi'an,Shaanxi 710065,China)

机构地区：[1]西安科技大学建筑与土木工程学院,陕西西安710054 [2]长安大学地质工程与测绘学院,陕西西安710054 [3]长安大学黄土科学全国重点实验室,陕西西安710054 [4]中交第一公路勘察设计研究院有限公司高寒高海拔地区道路工程安全与健康国家重点实验室,陕西西安710065

出　　处：《岩石力学与工程学报》2024年第6期1383-1396,共14页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(42277172,12072259);陕西省重点研发计划项目(2024SF-YBXM-626)。

摘　　要：寒区隧道普遍受到冻融作用影响,易发生沿着混凝土衬砌结构与围岩界面损伤与脱黏现象,严重影响隧道工程施工质量与安全运营。为提升隧道围岩-喷层界面黏结强度与抗冻性能,将围岩-喷层界面简化为岩石-混凝土二元体,研制适用于提升围岩-喷层界面黏结性与抗冻性的水泥基界面剂,并开展水泥基界面剂喷涂前后的砂岩-混凝土界面黏结强度及抗冻性能对比试验。试验结果表明:(1)冻融作用产生的岩石-混凝土界面中与硅氧四面体平行的主链破裂,是导致岩石-混凝土界面黏结性能降低的核心原因;(2)通过试验适配研制,提出适用于提升寒区隧道喷层界面黏结性与抗冻性的水泥基界面剂最优配合比为∶水泥∶水∶硅微粉∶硅烷偶联剂∶高分子胶凝材料(水性丙烯酸酯腹膜胶+竹材液化酚醛树脂)=10∶4.4∶0.8∶0.2∶1∶0.5;(3)因水泥基界面剂的高分子水化作用,喷层界面产生的“树根桩”效应扩大了岩石与混凝土接触面的栓堵程度,同时,硅烷偶联剂的化学键合作用提升了界面间的机械咬合力,二者耦合增强作用提高岩石-混凝土界面的黏结剪切强度和劈裂强度。通过对比试验发现,在冻融30次后,采用水泥基界面剂处理后,岩石-混凝土界面剪切强度较未处理试样可提升109%,黏结劈裂强度则提升了78%;(4)水泥基界面剂中硅氧烷水解缩合作用产生的硅氧键吸附在岩石-混凝土界面形成的疏水层,抑制了界面富水区扩展;而联合反应生成的硅凝胶发生相变释放热量,减少了岩石-混凝土界面冻融损伤,可抑制岩石-混凝土界面裂纹萌生与扩展。(5)研制的水泥基界面剂本身具有良好的抗冻性,特别是在-10℃~10℃的冻融环境中可高效发挥提升围岩-喷层界面黏结性及抗冻性的功能。研究为寒区隧道围岩-喷层界面增黏与抗冻处理提供了一种新的解决方案。Tunnels in cold regions are generally affected by freeze-thaw action,and is prone to damage and debonding along the interface between concrete lining structure and surrounding rock,which seriously affects the construction quality and safe of tunnel engineering operation.In order to improve the bonding strength and frost resistance of the tunnel surrounding rock-spray layer interface,the surrounding rock-spray layer interface is simplified into a rock-concrete binary body.The cement-based interfacial agent is developed for improving the adhesion and frost resistance of the surrounding rock-spray layer interface.A comparative test of the bonding strength and frost resistance of the sandstone-concrete interface was carried out before and after the spraying of the cement-based interface agent.The test results show that:(1)The main chain fracture parallel to the silicon-oxygen tetrahedron in the rock-concrete interface caused by freeze-thaw action is the core reason for the decrease of the bonding performance of the rock-concrete interface.(2)Through the test and development,the optimal mix ratio of cement-based interfacial agent suitable for improving the interfacial adhesion and frost resistance of tunnel spray layer in cold regions is proposed as follows∶cement∶water∶silica powder∶silane coupling agent∶polymer cementitious material(water-based acrylate peritoneal gel+bamboo liquefied phenolic resin)=10∶4.4∶0.8∶0.2∶1∶0.5.(3)Due to the polymer hydration of the cement-based interfacial agent,the'root pile'effect generated at the interface of the spray layer expands the degree of plugging on the contact surface between the rock and the concrete.At the same time,the chemical bonding of the silane coupling agent enhances the mechanical bite force between the interfaces.The coupling enhancement of the two improves the bond shear strength and splitting strength of the rock-concrete interface.Through comparative tests,it is found that after 30 freeze-thaw cycles,the shear strength of the rock-concrete in

关 键 词：隧道工程 岩石-混凝土 水泥基界面剂 冻融循环 黏结强度 抗冻性 

分 类 号：U45[建筑科学—桥梁与隧道工程]