The effects of fire on the bending strength of reinforced concrete beams

• Main Authors: Galang, Joaquin M., Molina, Marc Neal N.
• Format: text
• Language: English
• Published: Animo Repository 2008
• Subjects: Concrete beams—Effect of high temperatures on; Concrete beams—Fatigue; Civil Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/5404
• Institution: De La Salle University

The effect of fire on the flexural behavior of RC beams is investigated. Twenty-four reinforced concrete beams were constructed measuring 152 x 152 x 686 mm. Two (2) groups of beams were cast with different target concrete strengths, 20 and 30 MPa, exposed to fire at temperature above 300˚C for time durations of 0, 1, 2 and hours. Cooling was done at room temperature. The beams were tested using the third-pointy loading test (applying two transverse loads incrementally). The effect of elevated temperatures on the yield stress of steel inside the reinforced concrete beams was evaluated by talking the steel reinforcing bars from the beam after the beam was subjected to fire and testing the bars for their strength. Maximum loads and the load-deflection relationship of each beam was monitored and recorded. The percentage decrease in strength of the reinforced concrete beams as affected by exposure to fire was determined. Reduction in maximum loads and increase in deflection were observed. Maximum moment and yielding moment obtained from the experiment were compared to the theoretical nominal moment.