Performance Evaluation of Reinforced Recycled Aggregate Concrete Columns under Cyclic Loadings

Abstract

Recycled concrete aggregates (RCAs) generated from construction and demolition activities have been recognized as a feasible alternative to natural aggregates (NAs). Naturally, the columns fabricated with reinforced recycled concrete (RRC) have been proposed and investigated to promote the structural use of recycled aggregate concrete (RAC). There is still, however, very limited modeling research available to reproduce, accurately and efficiently, the seismic response of RRC columns under lateral cyclic loading; proper evaluations are also lacking on addressing the columns’ seismic behaviors. To fill some of those research gaps, a fiber-based numerical model is developed in this study and then validated with the experimental results published in the literature. Subsequently, the numerical model justified is applied to carry out a comprehensive parametric study to examine the effects of a range of variables on the hysteretic characteristics of RRC columns. Furthermore, a grey relational analysis is conducted to establish quantifiable evidence of key variable sensitivities. The evaluation results imply that the use of the additional water method (AWM) for manufacturing RAC is likely to reduce the lateral load-carrying capacity of the RRC columns (up to 10%), whereas the opposite would occur if a conventional mixing procedure is adopted. Moreover, compared with other factors such as steel area ratio, the content of RCA replacement has a less remarkable effect on the seismic performance of the RRC columns. In general, the RRC columns possess acceptable seismic-resistant properties, and they can be used in earthquake-prone regions with confidence.

Machine Learning-Based Evaluation of Shear Capacity of Recycled Aggregate Concrete Beams

“…Prior to conducting the ML-based analysis, it is useful to identify the importance of various parameters. Such a rehearsal can provide insights into whether the selected input parameters are appropriate [ 12 , 13 ]. To achieve this objective, the powerful mathematical tool of Grey relational analysis (GRA), which has been proposed to deal with poor, incomplete, and uncertain systems [ 76 ], was used in this study.…”

“…One of the biggest concerns is the inferior properties of RA, which would result in significant reductions in the mechanical properties of RAC [ 4 , 5 , 6 , 7 ]. This should impede the acceptance of RAC-based members, though many laboratory studies have revealed their structural feasibility [ 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. Another wave of concern is around design and modeling, where the validity of previous code-based models and analytical procedures developed for natural aggregate concrete (NAC) components is questioned for their RAC counterparts; this issue has begun to be systematically addressed [ 15 , 16 , 17 ].…”

Special Issue: New Trends in Recycled Aggregate Concrete

“…In their study, Wang et al [1] evaluated the performance of reinforced recycled aggregate concrete (RRC) columns under cyclic loading, using a fiber-based numerical model. With this model, they performed a comprehensive parametric study to examine the effects of a range of variables on the hysteretic characteristics of RRC columns.…”

Effect of recycled coarse aggregate on physical and mechanical properties of concrete

“…Many experimental investigations have been conducted on reinforced concrete columns with different CARR under uniaxial and cyclic compressive loading (Ajdukiewicz et al, 2007; Choi, 2017; Choi et al, 2012; He et al, 2017; Lei et al, 2020; Tam et al, 2014; Wang et al, 2015; Wang et al, 2019; Xiao et al, 2006, 2012; Zhang et al, 2017; Zhou et al, 2010). Zhang et al (2017) utilized 22 geopolymer/ordinary concrete specimens with different strength and demolished concrete lamps (DCL) were adopted as RCA.…”

“…Nevertheless, a frame structure with a higher content of RCA still behaved well enough to resist an earthquake attack. Xiao et al (2012), Wang et al (2019), and Lei et al (2020) investigated the seismic behavior of columns with RCA. The results from the three studies concluded that these columns have acceptable seismic properties and they can be used in severe earthquake regions.…”