No abstract

In this research, an investigational study on the use of CFRP laminates with 4 types of configurations (Series-A: laminated with confinement wrap, Series-B: single flat & L wrap, Series-C: confinement wrap, and Series-D: double flat & confinement wrap) to repair partially damaged reinforced cement composite column-beam joints is presented. The project's primary goal was to examine how retrofitting configurations affected the behaviour of repaired RC column-beam junctions when subjected to cyclic loads (FL + RL). To examine the effectiveness of repairs for enhancing the stiffness, strength capacity, and behaviour of damaged RC joints (Partially -25%, 50%, and 75%), seventeen samples were fabricated and investigated. Cyclic loading was used to test the control specimen all the way to failure. Sixteen samples were subjected to a load level that was around 75% of the projected pre-failure load (26 kN) under seismic condition. The maximum load, ductility index, and load versus displacement were all used to analyse the data. Also, CFRP debonding and the failure modes due to fracture pattern were observed. The findings highlighted the significance of repairing and improving joint performance. All repaired joints have increased strength that is virtually as strong as the beam-column joint's actual shear strength. As a result, compared to the reference specimen, the Series-D joints had a substantially greater strength capacity (30.77%).

Alkali-activated bricks are considered a sustainable alternative in masonry construction. These bricks are produced by reacting the waste materials in an alkaline environment using alkali activators such as sodium silicate and sodium hydroxide. In this study, our objective is to explore the viability of manufacturing alkali-activated bricks using industrial waste materials, specifically by fly Ash, Paper Mill Sludge Ash (PMSA), and Crusher Sand Dust (CSD). To reduce the reliance on fly ash, alkali-activated bricks are manufactured by substituting PMSA in two different melds. The first meld is performed to optimize the PMSA and the second meld is carried out to optimize the Crusher Sand Dust (CSD) as filler material. Meld 3 is used to investigate the impact of the NaOH molarity of the bricks ranging from 6 M to 14 M for the optimum proportions obtained from Melds 1 and 2. XRD, FT-IR, TGA, and SEM analyses were carried out to understand the mineralogical and chemical characterization of the raw materials and brick specimens. Furthermore, various tests were conducted on the bricks to assess their physio-mechanical properties, following the relevant standards outlined in IS requirements. Overall, this study demonstrates the feasibility of producing alkali-activated bricks by utilizing industrial waste materials. These findings offer promising prospects for creating sustainable construction materials while effectively addressing the issue of waste disposal.