Implementation of coupled thermal and structural analysis methods for reinforced concrete structures

Albostan, Utku
Temperature gradient causes volume change (elongation/shortening) in concrete structures. If the movement of the structure is restrained, significant stresses may occur on the structure. These stresses may be so significant that they can cause considerable cracking at structural components of large concrete structures. Thus, during the design of a concrete structure, the actual temperature gradient in the structure should be obtained in order to compute the stress distribution on the structure due to thermal effects. This study focuses on the implementation of a solution procedure for coupled thermal and structural analysis with finite element method for such structures. For this purpose, first transient heat transfer analysis algorithm is implemented to compute the thermal gradient occurring inside the concrete structures. Then, the output of the thermal analysis is combined with the linear static solution algorithm to compute stresses due to temperature gradient. Several, 2D and 3D, finite elements having both structural and thermal analysis capabilities are developed. The performances of each finite element are investigated. As a case study, the top floor of two L-shaped reinforced concrete parking structure and office building are analyzed. Both structures are subjected to heat convection at top face of the slabs as ambient condition. The bottom face of the slab of the parking structure has the same thermal conditions as the top face whereas in the office building the temperature inside the building is fixed to 20 degrees. The differences in the stress distribution of the slabs and the internal forces of the vertical structural members are discussed.


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Citation Formats
U. Albostan, “Implementation of coupled thermal and structural analysis methods for reinforced concrete structures,” M.S. - Master of Science, Middle East Technical University, 2013.