ABOUT THE INTERNATIONAL CONCRETE ABSTRACTS PORTAL

  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal

  


Title: High-Temperature Behavior of Lightweight Aggregate Reinforced Concrete Beams

Author(s): F. Dabbaghi, A. Tanhadoust, M. L. Nehdi, M. Dehestani, H. Yousefpour, and H.-T. Thai

Publication: Materials Journal

Volume: 119

Issue: 5

Appears on pages(s): 199-212

Keywords: finite element analysis; flexural capacity; lightweight aggregate; post-fire response; reinforced concrete; residual strength; stress-strain relationship

DOI: 10.14359/51736093

Date: 9/1/2022

Abstract:
Structural lightweight-aggregate concrete (LWAC) has gained a broad range of applications in the construction industry owing to its reduced dead load and enhanced fire resistance. In this study, the potential of using lightweight expanded clay aggregates as a partial replacement for fine and coarse natural aggregates was experimentally and numerically examined. Testing was performed on cylindrical specimens made of normalweight and lightweight concrete incorporating microsilica as a partial replacement for cement to determine the associated stress-strain behavior. Subsequently, three-point bending testing was conducted on reinforced concrete beams to evaluate their structural behavior. Four levels of temperature were considered: 25°C (ambient temperature), and 250, 500, and 750°C (elevated temperatures). The finite element method through Abaqus software was deployed to numerically investigate the behavior at elevated temperatures through a comprehensive parametric study. The experimental and numerical results indicate that under high-temperature exposure, LWAC outperforms its normal counterpart in terms of strength, stiffness, and Young’s modulus. It is also noticeable that LWAC beams retained their load-bearing capacity better than normal weight aggregate concrete (NWAC) after reaching the peak load.