This study evaluates the performance of lightweight aggregate deep beams strengthened with low-cost glass fiber-reinforced polymer composite (Lo-G) wraps as an alternative to expensive synthetic fiber-reinforced polymers (FRPs). The investigation includes side-bonded and fully wrapped configurations of Lo-G wraps, alongside carbon FRP (CFRP) strips for comparison. The experimental results show that epoxy-based anchors provided significantly better resistance against de-bonding than mechanical anchors, improving beam performance. Strengthening with Lo-G wraps resulted in a peak capacity increase of 17.0% to 46.9% for side-bonded beams in Group 2, 10.5% to 41.4% for fully wrapped beams in the strip configuration in Group 3, and 15.4% to 42.7% for CFRP strips in Group 4. The ultimate deflection and dissipated energy were also improved, with dissipated energy increases of up to 264.6%, 322.3%, and 222.7% for side-bonded and fully wrapped Lo-G wraps and CFRP strips, respectively. The side-bonded configuration with two or three Lo-G wraps, supplemented by epoxy wraps, outperformed fully wrapped 250 mm strips in peak capacity, with peak capacity improvements of up to 46.9%. However, beams with mechanical anchors showed poor performance due to premature debonding. They rely on friction and expansion within the concrete to resist pull-out forces. If the surrounding concrete is not strong enough or if the anchor is not properly installed, it can lead to failure. Additionally, reducing strip spacing negatively impacted performance. Lo-G wraps showed an 8.5% higher peak capacity and 32.8% greater dissipated energy compared to CFRP strips. Despite these improvements, while Lo-G wraps are a cost-effective alternative, their long-term performance remains to be investigated. None of the existing models accurately predicted the shear strength contribution of Lo-G wraps, as the lower elastic modulus and tensile strength led to high deviations in prediction-to-experimental ratios, underscoring the need for new models to assess shear strength.

The objective of this research is to study the Properties of Portland cement Type V mortar mixed with Ground Rice Husk Ash (GRHA) and two types of limestone powder (LS1 and LS2). The physical and chemical properties of Portland cement Type V, ground rice husk ash, and limestone powder were tested. The properties of mortar such as water requirement, compressive strength, compressive strength loss and drying shrinkage were investigated. The solutions used in this study were sodium sulfate (Na₂SO₄) and magnesium sulfate (MgSO₄). The concentrations of both solutions were 5% by weight in accordance with the ASTM C 1012 standard. GRHA, LSI, and LS2 have particle sizes of 29, 12 and 128 μm. The replacement levels of GRHA, LS1, and LS2 in Portland cement Type V were 0%, 20% and 40% wt. of cementitious materials. The ratio of water to cementitious material was controlled based on the water requirements conforming to flow value at 110 ± 5%. The results showed that the compressive strength of mortar was decreased with increase the percentage replacements of GRHA and LS in Portland cement Type V. At 180 days, the compressive strength of all mortars was lower than that of the control mortar. Mortar containing 20% of GRHA and LS (C80R10LS110) was the highest development in compressive strength and as high as that of the control mortar. From the results of sulfate resistance, it was found that the higher was the percentage replacements of GRHA and LS in Portland cement Type V, the lower was the strength loss and drying shrinkage of mortar. The strength loss of mortars in magnesium sulfate solution was more than those in sodium sulfate solution.