Thermo-Mechanical Properties of High Strength Concrete Reinforced With Nano-Micro Fibers Under Fire Conditions

Abstract

Carbon nano fibers (CNFs) and basalt fibers (BFs) were added into high strength concrete (HSC) to evaluate the fire resilience of incumbent matrix. The mechanical performance was evaluated by conducting material property tests namely compressive strength, tensile strength, stress–strain response, elastic modulus, compressive toughness and mass loss in the temperature range of 23oC to 800oC. Heating rate of 5oC/min was employed to expose the concrete cylindrical samples to targeted temperatures. Advanced techniques such as scanning electron microscopy (SEM) have been used for micro and nano forensics while the internal structure damage on exposure to fire was analyzed by ultrasonic pulse velocity (UPV) in macro-phase. The test results revealed better retention in mechanical and physical properties of high strength concrete containing CNFs and BFs. Mathematical relationships based on statistical analysis have been proposed for predicting mechanical, durability and energy related properties of HSC modified with varying percentages of CNFs and BFs at elevated temperatures.