Effect of non-structural masonry brick infill walls on the robustness of a RC framed building severely damaged due to a landslide

Abstract

Western countries are increasingly demanding for robust structures, i.e., structures capable of withstanding local damage caused by unforeseen extreme events without triggering a progressive collapse, thus reducing the magnitude and proportion of the resulting consequences.In this paper, the robustness of framed RC buildings is analysed by comparing the reliability of the damaged structure with that of the original structure and considering (or not) the contribution of the masonry infill walls. To validate the adopted methodology, this is tested on a residential RC building severely damage due to a landslide, herein considered as case-study. A numerical model of the original, as well as, of the damaged structure is defined using force-based finite elements with distributed plasticity. Masonry infill walls are modelled as equivalent internal struts. Monte Carlo simulation and FORM coupled with artificial neural networks and response surface polynomials are used in parallel to perform the reliability analyses of both original and damaged structures. Obtained results show that the masonry infill walls are fundamental to contain damage progression after the failure of a couple of columns. In fact, without these non-structural elements, the structure would lack in robustness, and the probability of failure would be above 99%. On the contrary, by considering the structural contribution of the masonry infill walls, the robustness of the structure would be circa of 30% corresponding to a failure probability of 6%.

Study on overstrength and ductility of reinforced concrete building with different infill through nonlinear analysis

“…Most of codes consider infills as a non-structural element. The study finds that the infills increases the robustness index of building which prevents the building from collapse by providing the alternative load path [5]. H. Chaulagain et al (2014) upon their parametric studies determined the lower value of inter-storey drift favoring the performance of building.…”

Effects of infill walls on load resistance of multi-story RC frames to mitigate progressive collapse

“…It was concluded that the infill masonry wall can enhance vertical resistance of bare frame by around 280% on average and up to 500%. According to numerical studies [21][22][23], the use of masonry infill walls for multi-story building can considerably increase robustness. Furthermore, studies [24][25][26][27][28] proved that, even with openings, infill walls could greatly improve the performance of bare frames significantly.…”

The influence of mortar strength on the mechanical behavior of ceramic and concrete structural masonry blocks

“…Initially, low strength materials and empirical calculation methodologies were applied, which resulted in more robust structures. The construction techniques were improved with the use of more resistant materials alongside new alternatives methodologies (Barros et al, 2019).…”

“…The non-reinforced structural masonry of concrete blocks is composed of mortar-laid blocks, that may contain reinforcements for constructive or binding purposes. This type of masonry consists of structural elements that have various functions, but collectively provide structural stability (Rizzatti et al, 2012;Barros et al, 2019). This technique can rationalize all construction stages, optimizing time, materials and human resources (Juste, 2001).…”