Despite the advantages of lightweight aggregate concrete (LWAC), its brittleness in compression has limited its vast application. Jacketing by fiber-reinforced polymer (FRP) tends to be one method to overcome this negative point. The current study attempted to recognize the FRP confinement impact on the LWAC compressive monotonic behavior. Both fine and coarse aggregates were Scoria aggregate. The variables include the type and number of FRP layers; 150 × 300 mm cylindrical specimens were wrapped with 1, 2, 3, and 4 layers of glass FRP (GFRP) and carbon FRP (CFRP) strips. An investigation was performed on the monotonic stress-strain curve belonging to LWAC confined with FRP, and key points, including ultimate stress and strain on the curve, were explored. The results revealed that the key points would significantly improve by increasing FRP layers. Although the influence of GFRP confinement on enhancing the ultimate strain appears to be more considerable than the CFRP confinement, CFRP jacketing of LWAC upgrades the ultimate strength to the higher level compared to wrapping with GFRP. Based on the interpretation of experimental results, a design-oriented stress-strain model was established to predict the monotonic compressive response of Scoria-LWAC circular specimens confined with CFRP and GFRP. The validity of the model was examined. The predicted output was appropriately in line with the experimental findings.
