Abstarct: Today, a significant percentage of structures in Iran and around the world are composed of reinforced concrete moment frxames. These frxames are known for their strength, durability, and ability to withstand various loads, making them suitable for a wide range of applications, from residential buildings to tall towers and industrial structures. Filling the space between reinforced concrete frxames with Masonry infills, used as space fillers and architectural partitions, is common. This composite system constitutes the majority of lateral load-bearing systems. The main issue with clay block infills is their inadequate ductility during earthquakes. Unfortunately, due to non-compliance with code requirements during construction and the neglect of interaction effects in design (because of existing complexities), infills are prone to causing and are often the source of irreparable life and financial losses during earthquakes. The conducted laboratory study led to the construction of specimens that were similar in terms of seismic details. Three concrete seismic frxame specimens were tested: an empty seismic frxame, an unstrengthened infilled seismic frxame, and a strengthened infilled seismic frxame. In this research, the reinforced concrete frxames were constructed with seismic details in accordance with the Iranian National Building Code, Chapter 9, and at a 1:2 scale. In-plane loading was applied using a 25-ton cyclic loading jack. Out-of-plane loading was applied using a 50-ton static jack. The strengthening method employed was baxsed on Appendix 6 of the Iranian Standard 2800, using alkali-resistant glass fiber grids and a shotcrete coating on the clay block infills. The in-plane loading protocol followed ACI 374.2- and was executed within the range of 0.02% to 6% drift ratio. For out-of-plane loading, the specimens were subjected to cyclic loading with gradual increase until reaching the infill's yield displacement. The results from comparing the specimens' performance indicated the positive effect of the applied strengthening method. In the investigated strengthening scheme, behavioral parameters including ductility, energy absorption, and stiffness were significantly improved in both in-plane and out-of-plane directions. The laboratory findings suggested that the use of mesh grids, due to their high flexibility, leads to more ductile and predictable behavior in clay block infills, which can effectively contribute to reducing life losses during and after an earthquake.