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Artificial lightweight aggregate (ALWA) can be used as a replacement for coarse aggregates to produce low-density lightweight concrete. It can reduce the total weight of structural members, and consequently, the seismic forces on the building can be minimized. When adding a certain amount of fibers to the concrete mixture, the concrete performance can be improved by enhancing bonding between the mortar matrix and aggregates. To find more robust results, the study of combining the ALWA and fibers needs to be investigated. This paper deals with the impact of carpet fiber on flexural strength and failure mode of ALWA concrete. The experimental work was conducted on 150x150x600 mm concrete beams with ALWA aggregates and a 0 to 1% carpet fiber fraction range. The test results show that the optimum flexural strength of the beam improves by 7.15% with a 0.47% carpet fiber addition. In contrast, the specimen's failure mode indicates that it does not happen suddenly, with the deflection quality experiencing a reduction of 24.32% due to the presence of fibers. The results offer valuable information on the progress of lightweight concrete and fiber concrete research, also will contribute to the future research of the ALWA concrete strengthened with fibers. [ABSTRACT FROM AUTHOR]

The addition of fiber in the structural elements has a bright prospect, as the performance of the concrete can be enhanced by improving the bonding between the mortar matrix and the aggregates, also developing a better behavior against the external load on the concrete materials. This paper investigates the effect of steel fibers on mortar specimens, focusing on the failure mode and behavior in the compressive and flexural tests. The experimental study was performed on the standard-size specimen with the size of 50x50x50 mm and 50x50x170 mm, respectively, for the compressive and flexural test specimens. The results reveal that the fibers' presence contributes significantly to the flexural and compressive strength related to the conventional specimens. The calculation of modulus of rupture compared to the first-cracking stress shows that the specimens can still have increasing stress after the cracks occurred. Moreover, the failure modes of the fiber specimens changed into the more ductile failure characteristic due to the bridging mechanism from the fibers. The result provides vital information on the related research. [ABSTRACT FROM AUTHOR]

Civil construction faces an immense challenge due to the damages caused by fire during the construction and service phases. Therefore, it is important to study fire being one of the most severe environmental conditions affecting structures in order to mitigate its effects. Moreover, fiber has been generally discovered to be effective as a reinforced material to improve the strength of concretes. This research was conducted to analyze the residual strength of concretes reinforced with aluminum fibers when exposed to high temperatures. This involved the preparation of 25 MPa concrete specimens with the addition of 0.2% fiber contents exposed to 400 °C and 800 °C temperature for 30 minutes after which their compressive and split cylinder strengths were measured. The result showed the fiber increased the compressive strength by 14.37%, 14.90%, and 2.00%, and the split cylinder strength by 47.27%, 44.29%, and 32.09% at 25°C, 400°C, and 800°C respectively in comparison with the normal concrete. [ABSTRACT FROM AUTHOR]

In this day and age, a rewarding and new structural strengthening technique for civil structures is steel wire rope (SWR) strengthening. The ideal technique for structural analysis is the finite element method. Nonetheless, it could be an expensive and a challenging task to develop a model through the finite element method for a simple problem, for instance, cross section analysis of reinforced concrete (RC) structures. Therefore, in order to predict the flexural behavior of T-section RC beams, strengthened in the negative moment region with bonded steel wire ropes, researchers performed an analytical validation through a program based on the modified compression field theory (MCFT), namely Response-2000. They chose experimental data from the test conducted on three T-section RC beams in 2012. Subsequently, the collected results were compared with calculations from the fiber-elements method, constructed in excel spread sheets. Reasonably precise calculations of load-deflection responses, up to the peak load, were offered by the developed analytical model, however, the ductility of the beams was underestimated. The validated model was then utilized to study the impact of SWR diameter on the behavior of strengthened beams. This analytical investigation reveals the effectiveness of SWR bonded systems as an alternative strengthening technique, with the aim of enhancing the flexural capacity of RC beams. [ABSTRACT FROM AUTHOR]