Graduation Semester and Year
Spring 2025
Language
English
Document Type
Thesis
Degree Name
Master of Science in Civil Engineering
Department
Civil Engineering
First Advisor
Dr. Raad Azzawi
Second Advisor
Dr. Antonio Balderrama
Third Advisor
Dr. Himan Jalali
Abstract
To investigate the seismic performance of high-rise RC buildings with steel fiber reinforced concrete (SFRC) columns and shear walls, a detailed numerical analysis was established using RISA-3D software on twelve-story RC buildings subjected to earthquakes. The variables included in this research are steel fiber volume fraction (SFVF), number of stories with SFRC columns and shear walls, and concrete strength grade. The mechanical properties of the concrete for each mix are evaluated experimentally. Three types of concrete mix designs were performed in the Civil Engineering Laboratory Building (CELB) using different dosages of steel fibers (0, 25lb/cy, and 70lb/cy). The properties of SFRC were evaluated by testing multiple specimens. In total, twelve-cylinder specimens of 4-inch diameter and 8-inch height were tested in the lab to predict the compressive strength and modulus of elasticity; nine-cylinder specimens of 4-inch diameter and 8-inch height were tested for the split tensile test; and nine beam specimens of 6*6*20 inch for modulus of rupture.
The experiments showed that increasing the steel fiber could significantly decrease the concrete damage level and improve ductility. Compared with plain concrete, the concrete compressive strength with 25 lb/cy, and 70 lb/cy steel fiber increased by 17.9% and 41.1%, respectively. The split tensile strength increased by 29.4% and 63.4%, respectively. In addition, the modules of elasticity and modulus of rupture are increased by 10.1%, 22.0%, 27.9%, and 58.7%, respectively. Subsequently, Numerical simulations were conducted on twelve-story high-rise RC buildings with SFRC columns and with or without shear walls subjected to seismic loading using the RISA-3D-V22.0.2 (2025) software, and results were compared with non-fiber RC buildings. Steel fiber reinforced concrete (SFRC) is used in earthquake-resilient structures due to its high tensile strength, low self-weight, good corrosion resistance, and linear elastic stress-strain relationship. SFRC is a multiphase composite material that randomly distributes steel fibers with high tensile strength, high elongation, and good stability in the matrix. The addition of steel fibers can effectively improve the disadvantages of ordinary concrete, such as low tensile strength, easy cracking, and poor deformation ability. These improvements indicated that applying SFRC with 25 lb/cy and 70 lb/cy in columns and shear walls in the high-rise RC building could effectively improve the seismic performance and compensate for the shortcomings of resilient columns and shear walls. Enhances the concrete's strengths and significantly improves the load-carrying capacity, stiffness, lifespan, and energy dissipation. The numerical analyses of high-rise RC buildings showed that adding 25lb/cy and 70 lb/cy of steel fiber to the concrete columns mix in the 12 stories of the RC building without shear walls decreases the roof drift by 9.12% and 17.85%, respectively, while adding 25lb/cy and 70 lb/cy of steel fiber to the concrete columns and shear walls mix in the 12 stories of the RC building with shear walls added at the corners of the building decreases the roof drift by 8.75% and 17.24, respectively.
Keywords
Concrete Composite, Steel Fiber, Seismic, High-Rise Building
Disciplines
Civil Engineering
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Azzawi, Ali, "STRUCTURAL PERFORMANCE OF HIGH-RISE RC BUILDINGS WITH SFRC COLUMNS AND SHEAR WALLS SUBJECTED TO SEISMIC LOADING" (2025). Civil Engineering Theses. 462.
https://mavmatrix.uta.edu/civilengineering_theses/462