EXPERIMENTAL RESEARCH ON WATER FLOW BEHAVIOUR IN A SINGLE CRACK OF CEMENT-BASED MATERIALS
Water flow in cracks is important for concrete structures in both functional anddurability senses. Water flow behavior in cracks of cement-based materials involves fluiddynamics,mass transfer and exchange processes between water and cracked surface. In thispaper an experimental permeation device is conceived to study the mechanical flow behaviorof water in narrow cracks with mass transfer and exchange deliberately screened. In the tests,a single crack is created on mortar disk specimens; the relative position of two cracked surfacesis adjusted and fixed to obtain different opening apertures. The topography of cracked surfacesis scanned by laser profilometer and characterized by the roughness exponent. By the experi-mental device,water flow through crack is measured under a constant pressure for differentopening apertures. Meanwhile,the water flow in narrow cracks is studied through finite elementmethod and laminar flow theory. The flowing rates from experiments,numerical analysis andtheoretical prediction are compared and analyzed in terms of crack opening aperture and surfaceroughness. The flow channeling on rough surface is identified responsible for the importantdeviation of water flow from numerical analysis and laminar flow in very narrow crackopenings.
crack water flow surface roughness profllometer flow channelling
Mingjun MA Xiaomei WANG Kefei LI
Key Laboratory of Structural Engineering and Vibration of China Education Ministry,Civil Engineering Department,Tsinghua University,Beijing,PR China
国际会议
The International Conference on Durability of Concrete Structures(2008年混凝土结构耐久性国际学术会议)
杭州
英文
1198-1203
2008-11-01（万方平台首次上网日期，不代表论文的发表时间）