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Full-scale testing of multiple span girders is scarce in the literature, often related to the complexity of loading setup and time constraints. The importance of full-scale tests is manifested in the fact that useful information regarding failure mechanisms can be obtained. In addition, important guidelines can be established for structural designers. Further, results from full-scale tests can help establish constitutive laws for various mechanisms involved in the response of actual structures. The structural performance of individual members can be assessed by monitoring their strains at service and ultimate loads. This study presents a comparison of experimentally monitored strains on longitudinal steel bars, stirrups, and prestressing tendons embedded in single and multi-span full-scale precast pre-tensioned girders. These girders were constructed and detailed to simulate the response of newly proposed straddle-type monorail girders. Single-span girders were tested under monotonic two-point service and ultimate loads, whereas multi-span girders were tested under both two- and four-point service and ultimate load. It was revealed that longitudinal steel and prestressing tendon strains monitored within single-span girders at service and ultimate loads were significantly higher than those recorded at corresponding locations in multi-span girders.

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This study has endeavored to produce eco-friendly coal ash-incorporated recycled aggregate concrete (FRAC) by utilizing wastewater effluents for environmental sustainability. The mechanical and durability efficiency of the FRAC manufactured were explored using different kinds of effluent by performing a series of tests at various ages. The considered kinds of effluent for the mixing of FRAC were collected from a service station, as well as fertilizer, textile, leather, and sugar factories. Scanning electron microscopy (SEM) was utilized to judge the microstructural behavior of the constructed concrete compositions. The outcomes revealed that using textile factory effluent in the manufacturing of FRAC depicted peak compressive and split tensile strength improvements of 24% and 16% compared to that of the FRAC manufactured using potable water. The application of leather factory effluent for the manufacturing of FRAC portrayed the highest water absorption (13% better than the control mix). The application of fertilizer effluent in the manufacture of FRAC presented the greatest mass loss (19% enhanced than the control mix) due to solution intrusion and the ultimate chloride ion migration (16 mm at twenty-eight days of testing). The summation of coal ash improved the mechanical behavior of the concrete and also caused a reduction in its durability loss of. The SEM analysis depicted that the textile factory effluent presented the most densified microstructure with the development of ettringite needles and CSH gel having refined the ITZ.

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