Seismic performance of squat thin reinforced concrete walls for low-rise constructions

Abstract

Thin reinforced concrete (RC) walls with single layer reinforcement have been used for houses and buildings in several Latin American countries. Although some design codes include recommendations for squat thin walls in low-rise constructions, its seismic performance has not been validated adequately in past earthquakes. This article presents the results of an experimental campaign of nine full-scale specimens conducted to characterize the influence of the steel type, the reinforcement ratio, and the wall thickness on the seismic behavior of squat thin RC walls with single layer reinforcement. Both welded wire and deformed bars were used as web reinforcement. Experimental results are used to develop nonlinear models to assess the seismic behavior of a prototype two-story house with welded wire reinforcement and deformed bars by means of incremental dynamic analyses. The experimental results show that the type of steel has the largest influence on wall seismic performance. The numerical results suggest that RC walls with single layer reinforcement are suitable for housing applications up to two stories in high seismicity regions, particularly walls detailed with deformed bars.

Simplified Strut-and-Tie Model for Shear Strength Prediction of Reinforced Concrete Low-Rise Walls

“…To examine the accuracy of the proposed strut-and-tie model, experimental wall strengths of 100 specimens collected from past experiments on RC low-rise walls failing in shear 12,19,22,[25][26][27][28][29][30][31][32][33][34][35][36][37] were compared with calculated shear strengths from the model. Subsequently, the predictions from the proposed strut-and-tie model were also compared with predictions from building codes 4,5 and other strut-and-tie models.…”

“…The proposed strut-and-tie model was verified with a total of 100 RC low-rise walls (wall height-length ratio [H w /L w ] less than 2.5) failing in shear that were selected from available literature. 12,19,22,[25][26][27][28][29][30][31][32][33][34][35][36][37] The analysis results show that the model is conservative in predicting the shear strength of RC low-rise walls with an average value of the ratio of the experimental shear strengths to calculated shear strengths V exp /V n of 1.35. While Hwang and Lee's model 15 has the average value V exp /V n of 1.29, which is the closest to 1.00, it overestimates the shear strength of 22 specimens whereas the proposed model only overestimates seven specimens.…”

In-plane drift characteristics of fully grouted reinforced masonry shear walls

“…Meanwhile, reconnaissance surveys after the Chile (2010) and New Zealand (2010/2011) earthquakes revealed that some RC shear walls in buildings have underperformed and implied the need for review of the design methodology, particularly the ductility levels considered in the design had to be reconsidered in the seismic design (Almeida et al 2017;Blandon et al 2018;Hube et al 2020). Those failed RC walls depicted local buckling of vertical reinforcement and sometimes combined with global instability failures.…”

Evaluación Experimental de la Resistencia Sísmica de Muros de Concreto Armado de Espesor Reducido en Viviendas de Baja Altura

“…Con respecto al comportamiento de muros delgados de CR, Blandon (2018) probó cuatro paredes para caracterizar el comportamiento de edificios de altura media a alta. Este artículo corresponde al trabajo de investigación realizada en la Pontificia Universidad Católica de Chile (Almeida, 2015), se muestra información adicional al trabajo realizado anteriormente por Hube et al, (2020) y describe las actividades experimentales de seis especímenes de muros delgados de hormigón armado a escala real con refuerzo interno de una sola capa. Los muros se detallan con diferentes tipos de acero, proporciones de refuerzo y espesores de muro.…”