Date of Defense
24-11-2025 10:00 AM
Location
F1-1118
Document Type
Thesis Defense
Degree Name
Master of Science in Water Resources
College
COE
Department
Civil and Environmental Engineering
First Advisor
Prof. Hilal El-Hassan
Keywords
BFRP bars, environment, temperature, concrete, sustained loading, durability, microstructure.
Abstract
This thesis is concerned with the long-term durability of basalt fiber-reinforced polymer (BFRP) bars embedded in moist concrete. The study focuses on the combined effects of exposure duration, elevated temperature, and sustained tensile stress, which together influence the mechanical and chemical stability of BFRP reinforcement in aggressive environments. The main objective is to evaluate the degradation mechanisms of BFRP bars subjected to coupled hygrothermal and mechanical conditions and to develop a predictive durability model capable of estimating service life under realistic climate scenarios. Concrete-encased BFRP bars were conditioned at three temperatures (20, 40, and 60°C), three durations (3, 6, and 9 months), and under sustained loads of 15% and 25% of ultimate tensile strength. Tensile tests, moisture uptake, matrix digestion, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were performed. An Arrhenius-based durability model was further developed using experimentally derived degradation rates and applied to climatic data from Dubai and Al Ain, United Arab Emirates. Experimental findings revealed progressive tensile strength loss, reaching 38% after 9 months at 60°C under 25% load. Moisture uptake, hydroxyl group formation, and reduction in glass transition temperature confirmed hydrolysis as the dominant deterioration mechanism, while SEM showed matrix disintegration and fiber debonding. The Arrhenius model generated service-life master curves, demonstrating faster degradation in Al Ain compared to Dubai due to higher climatic temperatures. The thesis establishes a direct link between environmental exposure, sustained load, and chemical degradation, while providing a predictive service-life model. By incorporating both sustained stress and real climate data, this study bridges the gap between laboratory durability testing and field-relevant service life prediction of BFRP-reinforced structures.
Included in
DURABILITY OF BASALT FIBER-REINFORCED POLYMER BARS IN MOIST CONCRETE UNDER SUSTAINED LOAD
F1-1118
This thesis is concerned with the long-term durability of basalt fiber-reinforced polymer (BFRP) bars embedded in moist concrete. The study focuses on the combined effects of exposure duration, elevated temperature, and sustained tensile stress, which together influence the mechanical and chemical stability of BFRP reinforcement in aggressive environments. The main objective is to evaluate the degradation mechanisms of BFRP bars subjected to coupled hygrothermal and mechanical conditions and to develop a predictive durability model capable of estimating service life under realistic climate scenarios. Concrete-encased BFRP bars were conditioned at three temperatures (20, 40, and 60°C), three durations (3, 6, and 9 months), and under sustained loads of 15% and 25% of ultimate tensile strength. Tensile tests, moisture uptake, matrix digestion, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were performed. An Arrhenius-based durability model was further developed using experimentally derived degradation rates and applied to climatic data from Dubai and Al Ain, United Arab Emirates. Experimental findings revealed progressive tensile strength loss, reaching 38% after 9 months at 60°C under 25% load. Moisture uptake, hydroxyl group formation, and reduction in glass transition temperature confirmed hydrolysis as the dominant deterioration mechanism, while SEM showed matrix disintegration and fiber debonding. The Arrhenius model generated service-life master curves, demonstrating faster degradation in Al Ain compared to Dubai due to higher climatic temperatures. The thesis establishes a direct link between environmental exposure, sustained load, and chemical degradation, while providing a predictive service-life model. By incorporating both sustained stress and real climate data, this study bridges the gap between laboratory durability testing and field-relevant service life prediction of BFRP-reinforced structures.