Zhang S.,Tianjin University |
Yu M.,Tianjin University |
Xiao F.,Mid South Design and Research Institute State |
Wang C.,Tianjin University |
Wang G.,Wuhan University
Journal of Performance of Constructed Facilities | Year: 2016
A numerical simulation method is presented to analyze the thermal and creep effects on structural performance of orifices in gravity dams during construction and operation period. Time-dependent conditions such as the changes of gravity load and water pressure, the concrete viscoelastic material properties, and the variations of environment temperature are all considered for numerical modeling. Compared temperature results obtained from heat transfer analysis with the monitored data around orifice, proposed model is verified to be a reliable tool for thermal-structural coupling analysis. This paper discusses temperature distributions of orifice concrete surfaces in contact with water or air. Tensile stress evolutions arising from temperature variations are investigated correspondingly. Subsequently, cracking risks of orifice with different environments and locations are calculated to evaluate orifice structural performance. Thermal and creep effects on the distributions of tensile stress and cracking risk are studied simultaneously. Results show that long-term thermal and creep effects play important roles in the structural performance of orifice, and orifice concrete surface in contact with air located at the middle part of the dam has a higher cracking risk than surfaces in contact with air or water close to the upstream or downstream of dam. © 2015 American Society of Civil Engineers.