RA V13 N1, Message from the Editor in Chief (January - April, 2023)

Abstract

JOURNAL OF THE LATIN-AMERICAN ASSOCIATION OF QUALITY CONTROL, PATHOLOGY AND RECOVERY OF CONSTRUCTION

http://www.revistaalconpat.org

It is a source of satisfaction and joy for the Revista ALCONPAT team to see the first issue of our thirteenth year published.

The objective of the Revista ALCONPAT (RA) is the publication of contributions resulting from basic or applied research directly related to the solution of problems related to quality control, pathology and recovery of constructions, being welcome in these areas related case studies.

This V13N1 edition begins with a paper from Brazil, where Andreza Frare and colleagues compare the performance of Canada and Brazil in studies related to the alkaline aggregate reaction (AAR) in concrete, through a qualitative, quantitative, and systematic review of the literature, in addition to using the VOSviewer software for co-citation and bibliographic coupling. The data collected indicates that Canada is the country that stands out the most in terms of AAR research in the world, while Brazil is in seventh position. The paper presented the research between the two countries, the existing methodologies to evaluate AAR and the research panorama on the subject in Brazil. Finally, the work showed that among the emerging issues on RAA there are knowledge gaps.

In the second work, Félix Ramírez-Cervantes and colleagues from Mexico develop a rule-based system that supports the determination of the structural health of multi-story buildings. Hardware description techniques are used through programmable logic using entity integration and hierarchical design with VHDL programming. The system is embedded in an FPGA that, through an algorithm, integrates a first stage where a group of ultrasound sensors collect a measurement that is interpreted to obtain the relative displacement of the story. In the second stage, an inference engine performs the evaluation. Results are presented using an experimental model where it is verified that the system is capable of determining the stability of the structure based on the relative displacement of the story.

The third article comes from Uruguay, where Patricia Vila and colleagues analyze the degree of alkali-silica reactivity defined according to the expansion limits adopted by international regulations, applying different test methodologies (mortar bar, concrete prism-accelerated methodology and concrete prism-traditional methodology) in a total of 19 aggregate samples. 37% of the samples present a different degree of reactivity comparing the mortar bar (14 days) and the concrete prism with traditional methodology and no correlation is observed in the expansion obtained by both. 26% of the samples presents a different degree of reactivity between the concrete prism with the accelerated methodology and with the traditional methodology, observing a correlation in the expansion obtained by both methodologies. In addition, due to the duration of the test, the use of the accelerated methodology in concrete is suggested to evaluate the reactivity of the aggregate.

In the fourth article from Brazil, Maria Silva Freitas and Gibson Rocha Meira study the transport capacity of chloride ions in concrete with additions of metakaolin and fly ash. To do this, they carry out surface electrical resistivity and chloride ion diffusion tests (NT Build 443). As a result, it was observed that the use of the additions used was efficient in delaying the entry of chloride ions, reducing the diffusion coefficient, Dns, and increasing the surface electrical resistivity, ρ, in the studied materials. The general relationship between Dns and ρ for the concretes studied can be expressed by Dns = 2,7E-7*ρ^-0,475 and the relationship between the chlorides accumulated in the concrete and the surface electrical resistivity can be expressed by Cl_acum = 4,09-0,20945𝜌.

The fifth article, by Alexander López and colleagues, comes from Mexico and evaluates the performance of the influence of sugarcane bagasse ash (CBC) as a filler in self-compacting concrete mixes (SCC), added with 0%, 5%, 10 %, 15%, 20% and 25% with respect to the weight of cement. The characterization of the ash was carried out by means of FTIR, FRX and DRX. The workability properties of CAC were determined by slump flow, J ring, L box, V funnel, Visual Stability Index, and compressive strength tests. According to the results, the percentages of 10 to 20% in the CAC mixtures obtain a satisfactory performance, evidencing outstanding workability and compressive strength parameters compared to works like those published in the literature.

The sixth work of this number is written by Alberto Hernández Oroza from Cuba. He evaluates different SonReb models to estimate the compressive strength in reinforced concrete elements made with Cuban cement and aggregates. Sclerometric index and ultrasonic pulse velocity measurements were performed on 9 columns designed with P-35 ordinary Portland cement mix. Eight models were compared, of which those proposed by RILEM and Tanigawa et al. showed an error of less than 4% with respect to the reference value, determined by breaking the specimen. The results obtained demonstrate the feasibility of using the models to estimate the compressive strength of concrete, using national materials.

The closing article is by Almir Barros da S. Santos Neto and colleagues from Brazil, who analyze the effects of thermal variation and drying shrinkage on a building with cast-in-place concrete walls. The walls and slabs of the building were discretized in the SAP2000 program using the Finite Element Method. The main tensile stresses in the walls and roof slab are analyzed, and the Service Limit State of Crack Formation is verified. The results show that the effects of the action of temperature and shrinkage due to drying of the concrete allow the development of main tensile stresses greater than the tensile strength of the concrete, provided for NBR 6118 (ABNT, 2014). It is found that thermal and shrinkage loads can result in cracking of the walls and roof slab.

We are sure that the articles in this issue will constitute an important reference for those readers involved with questions of evaluations and characterizations of materials, elements, and structures. We thank the authors participating in this issue for their willingness and effort to submit quality articles and meet the established deadlines.

At the beginning of 2023, I must give a wide appreciation to the original editorial staff and to those who have joined this initiative that has led us to where we are now. But without a doubt, the greatest recognition goes to our authors of articles, who have trusted our journal and have invested time, money, and effort to publish their research work with us, despite the fact that many of them have had better options in their moment. The recognition is extensive to our readers, like you, who read us and cite RA internationally.

At the close of this V13 N1 2023, 12 years after having started operations, our performance as Alconpat Journal was finally rewarded with our inclusion in one of the two best indexes for journals such as Elsevier's Scopus. Our Scopus membership has its historic beginning on December 29, 2022, the date on which we received approval from Elsevier. This is one more reason of celebration for our community that has made a scientific investment in our journal waiting for moments like this. Congratulations to all.

By the Editorial Board

Pedro Castro Borges   

Editor in Chief