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Creep of Concrete in Shell Structures: Nonlinear Theory
Turlybek Turkpenovich Mussabayev1, Zhmagul Smagulovich Nuguzhinov2, Darya Nemova3
1Construction Department, L.N. Gumilyov Eurasian National University, Kazhymukan 13, Astana 010000, Kazakhstan.
Materials (Basel, Switzerland)
|August 26, 2023
Summary
A new nonlinear theory for concrete creep in shell structures accurately predicts structural behavior. This approach improves safety and stability, offering effective control over concrete creep in engineering applications.
Area of Science:
- Civil Engineering
- Materials Science
- Structural Engineering
Background:
- Concrete creep is a significant challenge for structural development, impacting stability and safety.
- Existing linear theories inadequately account for the physical and mechanical properties of concrete creep in shell structures.
Purpose of the Study:
- To develop and validate a nonlinear theory for analyzing concrete creep in shell structures.
- To provide a more accurate method for predicting the stress-strain state and behavior of concrete structures over their lifecycle.
Main Methods:
- Replacement of the original shell with a continuous equivalent elastic shell.
- Derivation of nonlinear creep and crack growth equations.
- Development of a section deformation model and solving systems of differential equations for equilibrium, motion, and perturbation.
Main Results:
- The nonlinear theory accurately models the behavior of concrete shell structures throughout their lifecycle.
- Comparison with linear theory and experimental data reveals significant overestimation of critical loads by linear methods (up to 56% short-term, 39% long-term).
- The developed theory provides crucial data on load dependence on deformations, forces, and cracks.
Conclusions:
- The proposed nonlinear theory offers a robust framework for understanding and managing concrete creep in shell structures.
- This research enables effective control of the concrete creep process in practical engineering, enhancing structural safety and longevity.
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