Singha B.N.; Mondal G.2025-02-1720241http://dx.doi.org/10.1080/13632469.2024.2376625https://idr.iitbbs.ac.in/handle/2008/5468This study uses the finite element method to investigate partially infilled reinforced concrete frames under monotonic loading. A FE model of a fully infilled frame was validated against an existing experimental model and was used for further study on partially infilled frames. The study analyzes fourteen models with varying infill heights and conducts a parametric study on infill strength and aspect ratio. Results show that partial infill improves initial lateral stiffness and strength, forming a single off-diagonal compression strut. An implied macro model for estimating initial lateral stiffness is proposed. Study found, stronger infill causes plastic deformation in the column. � 2024 Taylor & Francis Group, LLC.encaptive-column; equivalent strut; lateral response; Partial infilled frame; short-columnNote