In this study, it was aimed to produce glass fiber reinforced concrete (GRC) samples cured with internal resistance by placing resistance wires at different distances within the concrete molds and applying electric current at various voltages, while the mold surfaces were covered with stretch film. The engineering properties of these samples were then investigated. Previous studies have shown that the mechanical properties of conventional concrete, which were subjected to different curing methods, improved compared to samples that did not undergo any curing process. This study aimed to enhance both the engineering properties of the concrete samples and to accelerate the curing process. Glass fiber reinforced concrete (GRC) with dimensions of 50×50×4 cm was produced, and 25, 35, and 45V resistances were applied to three different molds with wire spacing of 5cm, 6cm, and 7cm. With this application, the GRC samples were subjected to internal resistance curing for the first 24 hours. By applying three different voltages to molds with three different wire spacings, 9 concrete samples were produced, along with 1 reference sample that did not contain any resistance wires and was not subjected to any curing process, making a total of 10 different concrete samples. After curing, the concrete samples were cut into 16cm×4cm×4cm GRC mechanical test specimens. The obtained specimens were tested for 7, 14, and 28 day compressive strength, flexural strength, unit weight, and ultrasonic pulse velocity. To examine the microstructure of the GRC samples, Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA), and Fourier Transform Infrared Spectroscopy (FT-IR) analyses were conducted. These analyses investigated the physical and chemical development processes of the samples, mass losses, products formed after hydration, and structural behaviors. As a result, it was observed that the early-age strength properties of GRC samples cured with internal resistance showed a partial increase compared to the reference sample that was not internally cured, especially in the 7-day samples. In the 14 and 28-day strength comparisons, it was observed that the cured samples showed improvement in flexural strength. According to the data obtained, the samples subjected to 35 volts of electric current yielded better results, especially in the early ages, compared to the reference sample.
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