PSI - Issue 71

Varsha Harne et al. / Procedia Structural Integrity 71 (2025) 279–286

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behave, several experiments and numerical simulations were conducted. The results showed typical collapse patterns under lateral loads like earthquakes [Abdelkader Nour et al. (2023), Nicoletti et al. (2022), Nicoletti et al. (2020)]. Masonry infill walls are frequently excluded from consideration as structural elements. However, unlike other structural elements, they are vulnerable to inter-software action when placed within frames and exposed to seismic forces [Issam Abdesselam et al. (2023), Shing and Mehrabi (2002)]. It increases the building's stiffness and base shear while decreasing its natural period, resulting in higher seismic loads. The significant difference between the elastic behavior of columns and beams and the brittle behavior of masonry infill walls could have a severe impact on the seismic resilience of RC structures. The presence of masonry infill walls might produce many unwanted phenomena and failure mechanisms [Abdelkader Nour et al. (2023), Furtado et al. (2021)]. Many researchers now recognize that masonry infill walls must be integrated in the design of infilled RC buildings to more correctly portray the behavior of walls that infill the gaps formed by the connection of RC frames. [Abdelkader Nour et al. (2023), Eren et al. (2019), Jin (2015), Mansouri et al. (2014)]. However, a major drawback of infill walls, whether they are distributed uniformly or randomly, is their negative impact on the structure. [Guettala et al. (2023), IssamAbdesselam et al. (2023)]. This phenomenon is known as the eccentricity to concentrate displacement at the first floor and if the buildings are subjected to significant seismic activity, it may create soft-storey mechanisms. Seismic stresses can cause significant strains on even strong buildings, which could result in partial or total collapse [Guney and Aydin (2012), Issam Abdesselam et al. (2023)]. According to IS 1893:2016, a soft storey is defined as a storey in which the lateral stiffness is less than 70% of that in the storey above, or less than 80% of the average lateral stiffness of the three storeys above. Recent studies have shown a great lot of interest in the seismic resilience of soft-storey RCstructures [Issam Abdesselam et al. (2023), Tena-Colunga (2010)]. Additionally, it is common practice to calculate the lateral rigidity of a storey early in the design process, as this is considered a crucial step in identifying whether a structure has soft storeys. For differing degrees of precision, there are many approximation techniques for determining the stiffness of storeys. Nevertheless, the majority of these techniques are often used without accounting for the infill walls' role in increasing stiffness. The infill walls were disregarded throughout the design process since there was little information available on the behavior of quasi brittleness materials like masonry and because there were inconclusive experimental and analytical findings that would have demonstrated a trustworthy design methodology for these kinds of constructions [Asteris et al. (2011), IssamAbdesselam et al. (2023)]. Recent years have seen advancements in modeling and accurately characterizing the behavior of masonry infill walls. Two methods exist for simulating an infill-frame interaction: one is micro-modeling, which makes use of mortar and individual brick units. Using one or more struts is possible with the macro model, which is the second choice. Because of its ease of use and computational efficiency, this method is frequently applied, especially when doing seismic evaluations utilizing nonlinear static or dynamic analysis [Di Trapani et al. (2017), IssamAbdesselam et al. (2023)]. Therefore, the main objective of this paper should be addressed because it will be covered in more detail later on. The purpose of the project was to directly model the masonry infill walls in order to assess the seismic behavior of reinforced concrete buildings. The results were then compared while taking various parameters into consideration [Abdelkader Nour et al. (2023)]. 2. Methodology Conventional analyses used in earthquake regulations for building designs frequently focus on determining how structures would behave in specific scenarios of ground motion. These methods, which include response spectrum examination, linear dynamic, and static analysis, provide valuable perception about thestructural behavior and contributionto the stability of structures in moderate to severe earthquake situations. It is acknowledged that these standard analytical methods may not fully account for every possible mechanism of failure that could result in structural collapse. This insight has led to continued investigation and the creation of more sophisticated analysis techniques to improve the seismic design procedure. Alternative methods, such as nonlinear dynamic and static study have been investigated by researchers and engineers. Pushover analysis is a static-nonlinear method that gradually increases the amplitude of the lateral pressure while retaining the predetermined dispersion trend over the peak of the structure. This study uses ETABS v20 software to simulate and analyse G+10 storey RC frame structures with different configurations of infill walls for pushover analysis and meeting its objectives. Plastic assumptions implied nonlinear behavior by asserting the material distortions are localized on plastic hinges while the remaining portion of the structure behaves linearly elastically. The pushover curve can be generated by charting the roof displacement and base shear at each step. It provides a sense of the highest foundation shear that the building could withstand when the earthquake struck. Standard load combinations are used, as per IS:1893 Part 1 (2016). The structural reaction will be used to provide information about evolving features after the simulation.