Flexural and shear strengths of fiber modify lightweight aggregate concrete and its application in water-retaining structures

摘要

Purpose - The purpose of this study is to investigate the incorporation of lightweight aggregate concrete modify with fiber (LWACF) in water retaining structure. In developed countries LWACF is being successfully used as structural concrete; however, third-world countries such as Pakistan are still struggling to come up with the practical applications of lightweight concrete in the building and construction industry. One reason is because of the lack of reliable data regarding its performance as a structural member in the building and construction industry. Design/methodology/approach - The present study inspected the flexural and shear tolerance of fiber-reinforced LWACF by testing six beam specimens' cast, cured and tested after 28 days for the purpose. An overhead tank of 1,000-gallon capacity was also constructed to verify the application of LWACF by observing its water retention behavior. The experimental design included a mix design of concrete at a target strength of 21 MPa for control sample natural aggregate and for synthetic aggregate modified with polypropylene fibers. Compressive strengths of both categories of concrete were also determined by crushing the cylindrical samples at the age of 7, 14, 21 and 28 days. The cast beams were later subjected to the application of two-point loading test until failure. Findings - It was found that the beams fabricated with LWACF possessed better resistance to cracks compared with those fabricated with normal weight concrete, both in terms of number and crack width. The study also concluded that the constructed water tank with LWACF was thermally efficient and structurally sound, as it showed no sign of seepage for the observed period. Originality/value - On the basis of the results, it can be concluded that the LWACF used has revolutionized the concept of using lightweight aggregates in regular structures and that consequently it will help in a constructing a sustainable environment. One of the useful applications of such material is for water-retaining structures.