Contribution of RC columns and masonry wall to the shear resistance of masonry infilled RC frames containing different in size window and door openings

Abstract

In design, the contribution of the masonry infill wall to the shear resistance of the infilled frame structural system is often neglected. However, past research shows that ignoring this element can lead to inaccurate predictions of the system's behaviour. This paper investigates the influence of the opening type, size and position on the shear resistance and deformation capacity of individual components (infill and frame) in masonry infilled reinforced concrete (RC) frame structures. A computational model based on the non-linear finite element (FE) method of analysis has been developed. The computational model has been validated against a series of experimental tests carried out in the laboratory. An extensive parametric study was carried out and the influence of differences in size and location of window and door openings on the shear resistance of infilled frame was investigated. As a measure of the influence of the infill component, a shear resistance ratio for the frame was introduced. The normalized shear resistance capacity ratio represented the ratio of the shear force taken by the frame component (infilled frame case) divided by the shear force induced by the RC bare frame at observed drift ratios (damage grades). From the results analysis, it was found that the type of opening influences the design characteristics of the infilled RC frame. In particular, the shear resistance at columns of the infilled RC frame with a window opening is lower than the shear resistance of the columns of the RC frame. In contrast, the shear resistance at the columns of the infilled RC frame with a door opening is higher than the shear resistance of the columns of the RC frame, and in this case the contribution of the shear capacity of the frame is underestimated.

Computational micromodel for earthquake resstance evaluation of reinforced concrete fra-mes with masonry infill walls containing confined openings

“…Izvedba vertikalnih armiranobetonskih omeđujućih elemenata uz rub otvora omogućava znatna poboljšanja u ponašanju konstrukcijskoga sustava okvir-ziđe (Penava, 2012;Sigmund and Penava, 2014). Međutim, ako omeđujući elementi oko otvora nisu izvedeni pri gradnji, ponašanje ispunskoga ziđa postaje nepouzdanije, a time i potresni odziv ovih konstrukcijskih sustava podložniji nesigurnosti, iz razloga poput: mnogovrstan slom ziđa, nepričvršćenost okomito na ravninu ziđa, neodgovarajuće raspucavanje koje vodi k preuranjenom rušenju (Al-Chaar, Lamb and Issa, 2003;Decanini, Liberatore and Mollaioli, 2006;Kakaletsis and Karayannis, 2007, 2009Tasnimi and Mohebkhah, 2011;Sigmund and Penava, 2014;Penava et al, 2018). Omeđujući elementi nisu podložni proračunu kao okvirne konstrukcije i njihova razrada detalja temeljena je na jednostavnim preporukama.…”

Effect of Masonry Infill Constitutive Law on the Global Response of Infilled RC Buildings

“…Observations from past earthquakes demonstrate that masonry infill walls often behave as primary structural elements [3]. The distribution in plan and elevation of masonry panels strongly influences the behavior of the building at the global level leading to an increase of structure lateral stiffness [4][5][6], strength [7,8], and energy dissipation, and strongly affecting the seismic performances and the collapse mechanism [9] of the structures, and the building residual capacity [10][11][12][13]. Further, the presence of an irregular infill layout may lead to additional torsional effects or the development of soft-story mechanisms [14], while a regular layout contributes to the reduction of lateral deformations [6].…”

Performance evaluation of masonry Infilled RC frame structures under lateral loads

“…When choosing adequate model for MIFS, other questions are still disturbing designers: how to choose an optimum MIFS concept (dimensions of masonry panels, dimensions of RC frame elements, or dimensions of openings and their location), which can provide good performance under lateral solicitations? To answer, many studies of series of MIFS specimens with different configurations have so far been made [21,41,42]. In [41], the shear capacity of each MIFS is expressed by computing internal forces in masonry infills and making comparison with the corresponding RC bare element, in order to investigate the influence of size and position of openings.…”

“…To answer, many studies of series of MIFS specimens with different configurations have so far been made [21,41,42]. In [41], the shear capacity of each MIFS is expressed by computing internal forces in masonry infills and making comparison with the corresponding RC bare element, in order to investigate the influence of size and position of openings. In this work, a new methodology is proposed in order to evaluate performance of the masonry fully infilled frame structures (MIFS) based on the calculation of the indices of performance IP.…”