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22 pages, 16989 KiB

Open AccessArticle

Geopolymeric Composite Materials Made of Sol-Gel Silica and Agroindustrial Wastes of Rice, Barley, and Coffee Husks with Wood-Like Finishing

by Karina Rodríguez Espejel, José de Jesús Pérez Bueno, Coraquetzali Magdaleno López, Maria Luisa Mendoza López, Marcos Algara Siller, José Luis Reyes Araiza, Alejandro Manzano-Ramírez and Jorge Morales Hernández

Sustainability 2022, 14(24), 16689; https://doi.org/10.3390/su142416689 - 13 Dec 2022

Cited by 2 | Viewed by 1513

Abstract

Geopolymers have been mainly utilized as structural materials; their chemical structure and morphologies have been explored for their potential as a high-performance material in emerging applications. Geopolymer composites reinforced with materials based on agro-waste are attracting interest in engineering applications due to their [...] Read more.

Geopolymers have been mainly utilized as structural materials; their chemical structure and morphologies have been explored for their potential as a high-performance material in emerging applications. Geopolymer composites reinforced with materials based on agro-waste are attracting interest in engineering applications due to their easy processing, low cost, low density, and high strength-to-weight ratio. This investigation pursues an experimental methodology that consists of a scheme to make composites with a geopolymer matrix and agro-waste (rice husk, barley, and coffee) as aggregate material, that can be applied in various fields of construction. The study was intended to determine the influence of adding various agro-wastes on the mechanical properties of the geopolymer. According to the respective ASTM standards, the materials obtained were prepared and analyzed to determine their compressive strength, flexural strength, hardness and scanning electron microscopy (SEM)-determined characteristics. The results revealed that, for the compression tests, the composites formed by a sol-gel matrix and barley husk showed a better yield, obtaining the highest value of 3.5 N/mm². Concerning hardness testing, the composites with a geopolymer matrix and coffee husks obtained higher values compared to the other composites. For the flexural tests, the compounds with the sol-gel/fly ash matrix obtained the highest yield stress value, which was 5.25 MPa with an elastic modulus of 7.59 GPa. The results of the microstructural analysis showed good husk-matrix interaction, together with failure mechanisms. The conformation of such waste-based compounds may enable them to replace natural wood in some applications, such as in the finishing of interiors of homes, during the final stages in the construction of buildings, or in the decoration of inhabited houses, as well as in finishing in the manufacture of furniture. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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12 pages, 7825 KiB

Open AccessArticle

The Flexural Performance of BFRP-Reinforced UHPC Beams Compared to Steel and GFRP-Reinforced Beams

by Yazan Alhoubi, Zin Mahaini and Farid Abed

Sustainability 2022, 14(22), 15139; https://doi.org/10.3390/su142215139 - 15 Nov 2022

Cited by 5 | Viewed by 1139

Abstract

The performance of ultra-high-performance concrete (UHPC) reinforced with BFRP bars was investigated in this research study. To achieve the objectives of this study, a total of six UHPC beams were cast and tested for flexure, under displacement-controlled loading conditions. The performance of BFRP-reinforced [...] Read more.

The performance of ultra-high-performance concrete (UHPC) reinforced with BFRP bars was investigated in this research study. To achieve the objectives of this study, a total of six UHPC beams were cast and tested for flexure, under displacement-controlled loading conditions. The performance of BFRP-reinforced beams was compared against GFRP and steel reinforced beams. All beams had a cross-section of 185 mm × 250 mm, and a total length of 2200 mm. The experimental results were presented and discussed in terms of cracking moments, cracking patterns, failure modes, flexural capacity, midspan deflection, as well as strains in concrete and reinforcement. Results showed that UHPC enhanced the flexural performance of BFRP-reinforced beams in terms of moment capacity, deflection response and cracking patterns. The experimental results were complimented with analytical results that were calculated using the ACI 440 and CAN/CSA S806 code provisions. It was found that moment predictions using relevant ACI equations are acceptable for under-reinforced beams, but were slightly unconservative for the over-reinforced beams. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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23 pages, 8719 KiB

Open AccessArticle

Characteristics of Basalt Macro-Fiber Reinforced Recycled Aggregate Concrete

by Shahrukh Shoaib, Tamer El-Maaddawy, Hilal El-Hassan, Bilal El-Ariss and Marwa Alsalami

Sustainability 2022, 14(21), 14267; https://doi.org/10.3390/su142114267 - 01 Nov 2022

Cited by 5 | Viewed by 1765

Abstract

This study aims to examine the impact of using basalt macro-fibers (BMF) on characteristics of concrete made with recycled concrete aggregates (RCA). Test variables included the initial concrete grade (normal- and high-strength concrete (NSC and HSC)), RCA replacement percentage (30 and 60%), and [...] Read more.

This study aims to examine the impact of using basalt macro-fibers (BMF) on characteristics of concrete made with recycled concrete aggregates (RCA). Test variables included the initial concrete grade (normal- and high-strength concrete (NSC and HSC)), RCA replacement percentage (30 and 60%), and BMF volume fraction (ν_f = 0.5 to 1.5%). The compressive strength reduction in the plain concrete caused by RCA was sensitive to the RCA replacement percentage rather than the initial concrete grade. The splitting and flexural strength reductions of the plain HSC caused by RCA were more significant than those of their NSC counterparts. The use of BMF compromised the concrete workability. Such a detrimental effect increased with the BMF content and was more pronounced for the HSC with 60% RCA. Reinforcing of RCA-based concrete with BMF tended to improve the mechanical properties. In some instances, the use of BMF at ν_f > 1% caused a decay in the strength gain. The addition of BMF to RCA-based concrete had a potential to fully restore the original splitting and flexural strengths of plain concrete mixtures made with natural aggregates (NA). The increase in the compressive strength of the RCA-based concrete caused by BMF was, however, not sufficient to fully restore the original strength of the NA-based plain concrete. The resistances to water penetration and abrasion of the RCA-based concrete improved by up to 17% and 47%, respectively, due to the addition of BMF. Idealized tensile softening laws were established for RCA-based concrete reinforced with BMF. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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21 pages, 2643 KiB

Open AccessArticle

The Mechanical Behavior of Sustainable Concrete Using Raw and Processed Sugarcane Bagasse Ash

by Amr El-said, Ahmed Awad, Mahmood Ahmad, Mohanad Muayad Sabri Sabri, Ahmed Farouk Deifalla and Maged Tawfik

Sustainability 2022, 14(18), 11181; https://doi.org/10.3390/su141811181 - 07 Sep 2022

Cited by 7 | Viewed by 1376

Abstract

Sugarcane Bagasse Ash (SCBA) is one of the most common types of agricultural waste. By its availability and pozzolanic properties, sugarcane bagasse ash can be utilized as a partial replacement for cement in the production of sustainable concrete. This study experimentally investigated the [...] Read more.

Sugarcane Bagasse Ash (SCBA) is one of the most common types of agricultural waste. By its availability and pozzolanic properties, sugarcane bagasse ash can be utilized as a partial replacement for cement in the production of sustainable concrete. This study experimentally investigated the impact of employing two types of sugarcane bagasse ash as a partial substitute for cement up to 30% on the compressive strength, flexural strength, and Young’s modulus of the concrete mixture. The first type of bagasse ash used was raw SCBA, which was used as it arrived from the plant, with the same characteristics, considering that it was exposed to a temperature of 600 °C in the boilers to generate energy. The second type of bagasse ash utilized, called processed SCBA, was produced by regrinding raw SCBA for an hour and then burning it again for two hours at a temperature of 600 °C. This was done to improve the pozzolanic activity and consequently the mechanical properties of the concrete mixture. The findings indicated that employing raw sugarcane bagasse ash had a detrimental effect on the mechanical characteristics of the concrete mixture but using processed sugarcane bagasse ash at a proportion of no more than 10% had a considerable effect on improving the properties of the concrete mixture. The utilization of processed SCBA up to 10% into the concrete mixture resulted in a 12%, 8%, and 8% increase in compressive strength, flexural strength, and Young’s modulus, respectively, compared to the normal concrete specimen. On the contrary, the inclusion of raw SCBA with varying content into the concrete mixture decreased compressive strength, flexural strength, and Young’s modulus by up to 50%, 30%, and 29%, respectively, compared to the normal concrete specimen. The experimental findings were validated by comparison with ACI predictions. ACI overestimated the flexural strength of SCBA concrete specimens, with a mean coefficient of difference between the ACI equation and experimental results of 22%, however, ACI underestimated the Young’s modulus of SCBA concrete specimens, with a mean coefficient of difference between the ACI equation and experimental results of −6%. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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17 pages, 2765 KiB

Open AccessArticle

An Investigation of Mechanical Properties of Fly Ash Based Geopolymer and Glass Fibers Concrete

by Syed Nasir Abbas, Muhammad Irshad Qureshi, Malik Muneeb Abid, Asad Zia and Muhammad Atiq Ur Rehman Tariq

Sustainability 2022, 14(17), 10489; https://doi.org/10.3390/su141710489 - 23 Aug 2022

Cited by 9 | Viewed by 2023

Abstract

This paper presents an innovative approach towards the development of a green concrete. The geopolymer is an environmentally friendly construction/repairing material. In addition, glass fibers are helpful to influence the strength properties and to reduce hair line cracks and bleeding in concrete. This [...] Read more.

This paper presents an innovative approach towards the development of a green concrete. The geopolymer is an environmentally friendly construction/repairing material. In addition, glass fibers are helpful to influence the strength properties and to reduce hair line cracks and bleeding in concrete. This study is based on the use of fly ash and glass fibers as a partial replacement of cement and, subsequently, its effect on compressive strength and split tensile strength of concrete. The geopolymer is manufactured after the process of geopolymerization between class F fly ash and alkali activator fluid (sodium silicate and sodium hydroxide). In geopolymer concretes (GPC), an inorganic polymer called aluminosilicate will act as a binder, the same as conventional concrete has Portland cement (OPC)-generated C-S-H gel. The glass fibers are added in the ratios of 3%, 6%, and 10% by weight of cement. To check the effect of geopolymer and glass fibers on compressive strength and split tensile strength of concrete, concrete cubes of size 150 × 150 × 150 mm and concrete cylinders of size 150 × 300 mm with or without geopolymer and glass fibers were casted and cured for 7, 14, 21, and 28 days. The compressive strength and split tensile strength of all concrete cubes and cylinders were determined by compression testing machine. The findings of the research study revealed that concrete having geopolymer and glass fibers used as a partial replacement of cement showed lesser strength as compared to conventional concrete. Concrete having glass fibers showed reduced workability and more segregation as compared to geopolymer concrete and normal concrete. However, the concrete made either with geopolymer or glass fibers is economical as compared to conventional concrete. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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20 pages, 6304 KiB

Open AccessArticle

Optimization of Pervious Geopolymer Concrete Using TOPSIS-Based Taguchi Method

by Faiz Habib Anwar, Hilal El-Hassan, Mohamed Hamouda, Abdulkader El-Mir, Safa Mohammed and Kim Hung Mo

Sustainability 2022, 14(14), 8767; https://doi.org/10.3390/su14148767 - 18 Jul 2022

Cited by 19 | Viewed by 1831

Abstract

This paper evaluates the effect of mix design parameters on the mechanical, hydraulic, and durability properties of pervious geopolymer concrete (PGC) made with a 3:1 blend of granulated blast furnace slag (GBFS) and fly ash (FA). A total of nine PGC mixtures were [...] Read more.

This paper evaluates the effect of mix design parameters on the mechanical, hydraulic, and durability properties of pervious geopolymer concrete (PGC) made with a 3:1 blend of granulated blast furnace slag (GBFS) and fly ash (FA). A total of nine PGC mixtures were designed using the Taguchi method, considering four factors, each at three levels, namely, the binder content, dune sand addition, alkaline-activator solution-to-binder ratio (AAS/B), and sodium hydroxide (SH) molarity. The quality criteria were the compressive strength, permeability, and abrasion resistance. The Taguchi and TOPSIS methods were adopted to determine the signal-to-noise (S/N) ratios and to optimize the mixture proportions for superior performance. The optimum mix for the scenarios with a compressive strength and abrasion resistance at the highest weights was composed of a binder content of 500 kg/m³, dune sand addition of 20%, AAS/B of 0.60, and SH molarity of 12 M. Meanwhile, the optimum mix for the permeability-dominant scenario included a 400 kg/m³ of binder content, 0% of dune sand addition, 0.60 of AAS/B, and 12 M of SH molarity. For a balanced performance scenario (i.e., equal weights for the responses), the optimum mix was similar to the permeability scenario with the exception of a 10% dune sand addition. An ANOVA showed that the binder content and dune sand addition had the highest contribution toward all the quality criteria. Multivariable regression models were established to predict the performance of the PGC using the mix design factors. Experimental research findings serve as a guide for optimizing the production of PGC with a superior performance while conducting minimal experiments. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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20 pages, 3288 KiB

Open AccessArticle

Shear Response of Recycled Aggregates Concrete Deep Beams Containing Steel Fibers and Web Openings

by Nancy Kachouh, Tamer El-Maaddawy, Hilal El-Hassan and Bilal El-Ariss

Sustainability 2022, 14(2), 945; https://doi.org/10.3390/su14020945 - 14 Jan 2022

Cited by 14 | Viewed by 1791

Abstract

Replacement of natural aggregates (NAs) with recycled concrete aggregates (RCAs) in complex reinforced concrete (RC) structural elements, such as deep beams with openings, supports environmental sustainability in the construction industry. This research investigates the shear response of RC deep beams with openings made [...] Read more.

Replacement of natural aggregates (NAs) with recycled concrete aggregates (RCAs) in complex reinforced concrete (RC) structural elements, such as deep beams with openings, supports environmental sustainability in the construction industry. This research investigates the shear response of RC deep beams with openings made with 100% RCAs. It also examines the effectiveness of using steel fibers as a replacement to the minimum conventional steel stirrups in RCA-based deep beams with web openings. A total of seven RC deep beams with a shear span-to-depth ratio (a/h) of 0.8 were constructed and tested. A circular opening with an opening height-to-depth ratio (h₀/h) of 0.3 was placed in the middle of each shear span. Test parameters included the type of the coarse aggregate (NAs and RCAs), steel fiber volume fraction (v_f = 1, 2, and 3%), and presence of the minimum conventional steel stirrups. The deep beam specimens with web openings made with 100% RCAs exhibited 13 to 18% reductions in the shear capacity relative to those of their counterparts made with NAs. The inclusion of conventional steel stirrups in RC deep beams with openings was less effective in improving the shear response when 100% RCAs was used. The addition of steel fibers remarkably improved the shear response of the tested RCA-based beams. The gain in the shear capacity of the RCA-based beams caused by the inclusion of steel fibers was in the range of 39 to 84%, whereas the use of conventional steel stirrups resulted in 18% strength gain. The use of 1% steel fiber volume fraction in the RCA-based beam with openings without steel stirrups was sufficient to restore 96% of the original shear capacity of the NA-based beam with conventional steel stirrups. The shear capacities obtained from the tests were compared with predictions of published analytical models. The predicted-to-measured shear capacity was in the range of 0.71 to 1.49. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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Review

Jump to: Research

22 pages, 8668 KiB

Open AccessReview

A Bibliometric Analysis of the Studies on Self-Healing Concrete Published between 1974 and 2021

by Mohammed H. Alzard, Hilal El-Hassan, Tamer El-Maaddawy, Marwa Alsalami, Fatma Abdulrahman and Ashraf Aly Hassan

Sustainability 2022, 14(18), 11646; https://doi.org/10.3390/su141811646 - 16 Sep 2022

Cited by 11 | Viewed by 2550

Abstract

Research on self-healing concrete has flourished in recent years. This paper aims to comprehensively understand the current research situation and future development directions of self-healing concrete. It summarizes and analyzes the publications on self-healing concrete from 1974 to 2021 to reveal the current [...] Read more.

Research on self-healing concrete has flourished in recent years. This paper aims to comprehensively understand the current research situation and future development directions of self-healing concrete. It summarizes and analyzes the publications on self-healing concrete from 1974 to 2021 to reveal the current key research topics and development trends and identifies the most productive research constitutes. The bibliometric analysis software Biblioshiny was used to analyze 1433 documents written by 2961 authors and published in 450 sources retrieved from Scopus. The analysis included an overview of the leading information and an analysis of the authors, countries, universities/institution, publications, and keywords. Results obtained from the author analysis suggest that tracking the work of the most productive authors is essential, as it will provide researchers with valuable information, such as possible leads and ideas for future research work and collaboration opportunities. Countries, universities/institutes, and publications analysis revealed that more collaboration leads to more exposure and a higher citation rate, significantly promoting self-healing research development. A keywords analysis highlighted the focus areas in self-healing concrete and presented potential gaps in the literature. The findings of this study will provide scholars with a comprehensive understanding of the current research work in the field of self-healing concrete and its future directions. Results can also benefit stakeholders in making effective decisions to direct the development of the self-healing industry. Full article

(This article belongs to the Special Issue High Performance and Advanced Construction Materials)

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