Abstract
This works intends to analyze, experimentally and numerically, the bond-slip behavior between steel and concrete made with recycled aggregates (RA) from construction and demolition waste (CDW) from several recycling plants in Portugal. Pull-out tests performed in concrete mixes with RA from CDW are described and the main results (bond strength, bond-slip curves and failure modes) are shown and discussed. Additionally, a comparison between experimental and analytical (using equations from the literature) results is made. Afterwards, finite element (FE) models using Abaqus are developed and compared with the experimental results. The interface behavior between steel and concrete follows that prescribed by the CEB-FIP Model Code and uses as input experimental results. After validation, the models show good results when extended to predict the bond-slip behavior of the remaining concrete mixes studied. It is generally concluded that, per each 10% of natural aggregates replaced with RA from CDW, the bond strength decreases in circa 3% (numerically) to 5% (experimentally). CEB-FIP Model Code equations are shown to be able to predict bond strength and, when used in FE models, to lead to accurate simulation of the bond-slip response of steel and concrete with RA from CDW: the average ratio between numerical and experimental bond strengths is 0.95. In the scope of the FE models developed, a simple equation to be used along with those prescribed by CEB-FIP, which accounts for fraction and ratio of aggregates replaced, is put forward, as a first approach, showing good results.
Highlights
High quantities of natural resources and energy are consumed annually by the construction industry leading to a high generation of construction and demolition waste (CDW)
Considering the influence of recycled aggregates (RA) from CDW on the bond strength, it can be concluded that, on average, for each 10% increase of RA from CDW, the bond strength decreases between 3.9% and 6.0%
Considering the results shown above, it is possible to state that if (i) the compressive strength; (ii) fraction; and (iii) replacement ratio of natural aggregates (NA) with RA from CDW of a given concrete mix are known, its bond-slip behavior can be modelled using (iv) the bond-slip law proposed by the FIB Model Code [47] and (v) the slips estimated by simple equations such as Equations (10) and (11) proposed
Summary
High quantities of natural resources and energy are consumed annually by the construction industry leading to a high generation of construction and demolition waste (CDW). Zuhud [35] obtained an increase in the steel–concrete bond strength with the incorporation of RA in concrete, justifying this result with the higher roughness of RA This author states that the higher roughness of RA may cause a higher friction between RA and the ribbed rebars. This study intends to contribute to the understanding of the bond-slip behavior between steel and concrete with RA from CDW by presenting experimental and numerical results on this topic For this purpose, several concrete mixes with RA from distinct recycling plants were analyzed. Afterwards, with the obtained experimental results, the authors proceeded with the numerical simulation that allowed the prediction of the bond-slip behavior between steel and concrete with RA from CDW This extensive and relevant process constitutes the main innovation of the work reported.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
