Nonlinear coupled thermal-structural analysis of precast concrete beam-to-column connections at high temperatures
Noor Azim Mohd. Radzi, Muhaimim Kamal, Shareen Azuha, Nur Izzatie Aqilah Mansor, Roszilah Hamid
Department of Civil Engineering, Universiti Kebangsaan Malaysia, Selangor D. E., Malaysia
Finite element analysis;
This paper presents a nonlinear coupled thermal-structural analysis using ANSYS Workbench to determine precast beam-to-column connections' thermal and structural behaviour. Three precast connection models, a concrete corbel, a concrete nib, and an inverted E steel nib, are exposed to ambient and cellulose fire curves. Firstly, the precast connection models are verified based on the previous experimental result at ambient temperature. Then, the verified precast connection models are exposed to the cellulose fire curve for two hours before being loaded to failure. The results are compared with the recent experimental fire test conducted by the authors. Based on the result, finite element models at ambient temperature were validated with a percentage difference of less than 10%. However, finite element models at high temperatures were not verified due to the percentage difference exceeding 10 %. The significant difference was due to the non-uniformity of sample dimensions and different test setups in the previous experiment. Finite element models for concrete corbel and inverted E steel nib have a higher stiffness than the experimental sample. However, the finite element model for concrete nib has a lower stiffness than the experimental sample. Concrete nib recorded the most significant thermal percentage deterioration (32.1 % and 57.4 %) compared to concrete corbel (22.4 % and 11.52 %) and inverted E steel nib (26.9 % and 27.9 %). The validation result of nonlinear coupled thermal-structural analysis executed using ANSYS Workbench gives good efficiency for predicting the fire performance of precast concrete corbel beam-to-column connections at high temperatures.
© 2023 MIM Research Group. All rights reserved.