Methodology for Rapid Estimation of Deflections in Two-Way Reinforced Concrete Slabs Considering Cracking
Publication: Practice Periodical on Structural Design and Construction
Volume 26, Issue 2
Abstract
The codes of practice do not provide a methodology for estimation of deflection in two-way reinforced concrete (RC) slabs. Hence, a methodology has been proposed for immediate estimation of central deflections in two-way RC slabs considering cracking under service load for use in everyday design. The methodology covers the derivation of a closed-form expression for deflections in two-way simply supported RC slabs. The terms of the expression are based on weights, biases, and transfer functions from the developed supervised artificial neural network (ANN). First, a sensitivity analysis has been performed to identify significant input parameters for generating the data sets. The training, validating, and testing data sets for the development of the ANN are produced through an automated process using a programmed Python script and the finite-element software ABAQUS in accordance with the selected significant input parameters. The expression predicts the inelastic deflection (considering cracking) from the elastic deflection (neglecting cracking). In order to gain general applicability, the expression has been verified for a number of slabs that differ in size and reinforcement detailing. The small differences indicate that it can be used for preliminary design purposes. The use of the closed-form expression requires a computational effort that is a fraction of that required in iterative procedures available in the literature. The proposed methodology can be applied under different types of support conditions of the two-way slabs.
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Data Availability Statement
The data sets generated for this study is available from the corresponding author upon reasonable request.
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Published In
Practice Periodical on Structural Design and Construction
Volume 26 • Issue 2 • May 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Apr 13, 2020
Accepted: Nov 24, 2020
Published online: Jan 15, 2021
Published in print: May 1, 2021
Discussion open until: Jun 15, 2021
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