Influencia del fuego en la resistencia a compresión del hormigón elaborado a partir de material reciclado

Abstract

Because concrete is a material widely used in construction characterized by its high compressive strength, factors such as fire could cause problems in its internal and external functionality. That said, the objective of this research is to analyze the behavior that concrete with recycled aggregate will have, coming from residual concrete, whose purpose is to obtain experimental results that demonstrate how fire affects its compressive strength. For this experimental investigation, the optimal density method will be used to design the dosage with a resistance of 240 kg/cm2, within which 45 cylindrical test tubes were made, distributed 15 each with replacements of 0, 15 and 30 percent of natural aggregate by recycled aggregate. The specimens, after being cured at 28 days of age, were subjected to direct fire by means of a smelting furnace. With the help of a pyrometer, the temperatures that were exposed were controlled, which range from 0, 250, 400, 600 to 800 degrees Celsius during a determined period of time. For each temperature, 3 cylindrical concrete samples will be tested. Once exposed to the fire, they were cooled for 24 hours, to later be tested for compression. From the results obtained, it is shown that the compressive strength decreases as a function of each increase in temperature, looking unfavorable to those specimens that were replaced with 30 percent RA, in addition to this, various pathologies such as cracks, fissures, color changes and the phenomenon of chipping or spalling occurred.