隧道混凝土防水性能研究  

Research on the Watertightness of Tunnel Concrete

作　　者：王育江[1] 钱春香[1] 王辉[1] 黄蓓[1] 

机构地区：[1]东南大学材料科学与工程学院、江苏省土木工程材料重点实验室,南京211189

出　　处：《现代隧道技术》2009年第1期76-80,共5页Modern Tunnelling Technology

基　　金：教育部新世纪优秀人才基金(NoNCET-05-0473);江苏省六大高峰人才基金;南京长江隧道科技攻关项目

摘　　要：从多孔介质渗流力学角度出发,研究了水在混凝土中的渗流规律,通过试验测定了混凝土的渗透系数和启动压力梯度,并结合非Darcy渗流理论分析了水在混凝土内渗透深度和时间的关系。结果表明,混凝土的渗透系数极低;水在渗透过程中存在一个平衡深度;隧道混凝土可以达到较高的抗渗等级,而抗渗等级法不适合评价高强混凝土。通过研究,提出抗收缩能力才应是防水混凝土的关键问题所在,并希望在今后的防水混凝土配合比设计中得到足够重视。Seepage flow in concrete was studied in this paper based on fluid mechanics in porous medium. The permeability coefficient and starting pressure gradient of concrete were calculated through tests. The relationship between the penetration depth of water and time was also analyzed according to non-Darcy flow theory. Result indicated that the permeability coefficient of concrete is extremely low; there exists a balanced depth in the process of water permeation because of the starting pressure gradient; tunnel concrete has a high seepage resistance grade and the method of seepage resistance grade is not suitable for high strength concrete. Based on the study, it is postulated that the shrinkage resistance of concrete is the key problem of the watertight concrete, and hoped that to the dimensional stability of concrete should be paid enough attention in concrete mix design.

关 键 词：隧道 防水混凝土 渗透性 非达西渗流 启动压力梯度 平衡深度 配合比 

分 类 号：U453.6[建筑科学—桥梁与隧道工程]