隧道排水系统快速结垢成因分析及抑制技术研究  

Analysis of Rapid Scaling Causes in Tunnel Drainage System and Relevant Inhibition Technologies

作　　者：蒲春平 陆加越[2,3] 穆松 谢德擎[2,3] 周莹 PU Chunping;LU Jiayue;MU Song;XIE Deqing;ZHOU Ying(Guangdong Road and Bridge Construction Development Co.,Ltd.,Guangzhou 510655;Jiangsu Research Institute of Building Science Co.Ltd.,State Key Laboratory of High Performance Civil Engineering Materials,Nanjing 210008;Jiangsu Sobute New Materials Co.Ltd.,Nanjing 211103)

机构地区：[1]广东省路桥建设发展有限公司,广州510655 [2]江苏省建筑科学研究院有限公司高性能土木工程材料国家重点实验室,南京210008 [3]江苏苏博特新材料股份有限公司,南京211103

出　　处：《现代隧道技术》2023年第5期254-261,共8页Modern Tunnelling Technology

基　　金：国家自然科学基金(52078240);广东省交通集团科技项目“湿热环境中隧道工程衬砌混凝土耐腐蚀关键技术研究”。

摘　　要：隧道排水系统快速结垢堵塞,将引起支护背后水压增大,诱发衬砌渗水、变形、垮塌等二次病害。以广东某隧道在建设期间出现严重的初期支护渗漏结晶与排水系统结垢堵塞现象为例,通过分析围岩水流向、水质中离子浓度的时空变化与结垢矿物组成,分析了排水管碳酸钙快速结垢的成因,明确了初期支护混凝土对排水系统结垢堵塞起到关键作用。进一步研究有碱速凝剂、无碱速凝剂及密实疏水材料对初期支护混凝土抗溶蚀性能的影响。结果表明:初期支护混凝土析出Ga2+与OH-,促使围岩水pH值约从7.5提升至约10.5,加速碳酸钙结垢产物的生成;相较于初期支护单掺有碱速凝剂,复掺无碱速凝剂与疏水材料,初期支护28 d抗压强度提升35.3%、RCM降低26.6%、吸水率降低68.1%,通过基体密实疏水协同技术,内部氢氧化钙的溶解与析出得到显著抑制;工程应用则直接证实初期支护混凝土基体密实疏水技术可有效缓解排水系统结垢堵塞现象。Rapid scaling and blockage of the tunnel drainage system will increase the water pressure behind the support,leading to secondary defects such as water seepage,deformation and collapse of lining.In this study,a tun⁃nel in Guangdong province is used as a study case,which experienced severe leakage and crystallization of initial support,and scaling blockage in the drainage system during construction.The causes of rapid scaling of calcium car⁃bonate in the drainage pipe are studied by analyzing the flow direction of surrounding rock water,spatio-temporal changes in ion concentration in water quality analysis,and the composition of scaling minerals.It is clarified that the initial support concrete plays a key role in scaling blockage in the drainage system.Further research is conducted on the effects of alkali accelerator,alkali-free accelerator,and densifying hydrophobic material on corrosion resis⁃tance of initial support concrete.The results show that the precipitation of Ga2+and OH-from the initial support con⁃crete raises the pH value of the surrounding rock water from approximately 7.5 to 10.5,accelerating the generation of calcium carbonate scaling products;Compared to the initial support concrete mixed with only alkali accelerator,the initial support concrete mixed with combined alkali-free accelerator and hydrophobic material shows a 35.3%in⁃crease in 28 d compressive strength,a 26.6%decrease in RCM,and a 68.1%decrease in water absorption.By utilizing the densifying and hydrophobic collaborative technology for the matrix,dissolution and precipitation of internal cal⁃cium hydroxide are significantly inhibited;The engineering application directly proves that the densifying and hydro⁃phobic technology for initial support concrete matrix can effectively alleviate scaling and blockage in the drainage system.

关 键 词：隧道排水系统 结垢堵管 无碱速凝剂 密实疏水材料 PH值 

分 类 号：U457.5[建筑科学—桥梁与隧道工程]