Spreadsheet Calculation of Energy Based Method to Predict Temperature in Concrete Slabs

P. Panedpojaman

doi:10.15866/ireche.v14i1.23215

Spreadsheet Calculation of Energy Based Method to Predict Temperature in Concrete Slabs

P. Panedpojaman^(1*)

^(*) Corresponding author

Authors' affiliations

DOI: https://doi.org/10.15866/ireche.v14i1.23215

Abstract

Under various fire scenarios, both heat transfer analysis and structural analysis are required to assess fire resistance of reinforced concrete member. For heat transfer analysis, Finite element method and Finite difference method are complicate for practical use. To simply predict temperature in concrete slab, the energy based method is a simplified FDM based on the predetermined temperature profile and the energy conservation. However, the method provides an inaccurate temperature prediction. To improve the prediction accuracy, this study reformulates the energy based method and investigates a suitable predetermined temperature profile. Furthermore, to facilitate design engineers, the method is proposed as a simple spreadsheet calculation. Through the empirical study of the FEM temperature profile, the exponent is found to be logarithmic proportional to the ratio of the lowest temperature to the highest in concrete slabs. The power function with variation of the exponent provides the better accurate temperature prediction. Comparing with FEM analysis and experimental results, the spreadsheet calculation is validated for temperature prediction of concrete slab under various fire loads.
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Keywords

Concrete Slab; Energy Based Method; Fire Loads; Spreadsheet Calculation; Temperature Prediction

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References

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