Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
5.2
3.4
Journals
Materials
Special Issues
Mix-Design and Behavior of Special Concrete
materials-logo
Submit to Materials Review for Materials Propose a Special Issue

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

Mix-Design and Behavior of Special Concrete

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Construction and Building Materials".

Deadline for manuscript submissions: closed (10 August 2022) | Viewed by 12391

Special Issue Editor

Prof. Dr. Hugo Costa

E-Mail Website
Guest Editor
1. Department of Civil Engineering - Instituto Superior de Engenharia de Coimbra (Polytechnics of Coimbra), Rua Pedro Nunes, 3030-199 Coimbra, Portugal
2. Civil Engineering Research and Innovation for Sustainability (CERIS), University of Lisbon, 1049-001 Lisbon, Portugal
Interests: mix design of cementitious materials; mechanical, time dependent and durability behaviors of special concretes
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Reinforced concrete is the most widely structural solution all over the world, due to the huge versatility and reduced cost both for precast and in situ construction. The increasing different specifications for concrete behavior, which result in many different concrete construction projects and various requirements, are constantly challenging the mix design of special concretes. Those are normally related with specific requirements, aiming to increase strength, toughness, and durability performances, or even to reduce concrete weight. However, the environmental concerns are related to the production of ordinary Portland cement, which highly contributes to greenhouse gas emissions. Therefore, various studies have been recently conducted in order to develop new and more eco-efficient special concretes by reducing or eliminating Portland cement to obtain enhanced eco-efficiency of the concrete binder matrix and by combining with those special concretes already known.

This Special Issue aims to cover the latest developments in mix-design and behavior of new special concretes. It covers not only special concretes, such as lightweight, high and ultra-high performance, self-compacting and fiber-reinforced, alkali-activated, and geopolymer-based concretes with recycled aggregates, but primarily those combined with eco-efficient binder matrices. Those matrixes are mainly obtained by replacing the Portland cement proportions via sustainable and supplementary cementitious materials, or by developing new binder solutions with special and eco-friendly cements and clinkers, or even by alkali-activated binders. Therefore, original papers dealing with new advances and challenges in new special concretes are highly welcome, namely concerning mix-design and production, rheology, hydration, and microstructure, as well as physical, mechanical, time-dependent, and durability properties. Service life assessment, sustainability, and modeling are also invited to this Special Issue.

Dr. Hugo Costa
Guest Editor

Keywords

  • Special concrete
  • Mix-design
  • Characterization
  • Lightweight
  • Special cement
  • Low cement binder
  • Eco-efficiency
  • Life assessment and sustainability
  • Modelling

Published Papers (6 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

17 pages, 4068 KiB  
Article
Intelligent Design of Building Materials: Development of an AI-Based Method for Cement-Slag Concrete Design
by Fei Zhu, Xiangping Wu, Mengmeng Zhou, Mohanad Muayad Sabri Sabri and Jiandong Huang
Materials 2022, 15(11), 3833; https://doi.org/10.3390/ma15113833 - 27 May 2022
Cited by 17 | Viewed by 1623
Abstract
Cement-slag concrete has become one of the most widely used building materials considering its economical advantage and satisfying uniaxial compressive strength (UCS). In this study, an AI-based method for cement-slag concrete design was developed based on the balance of economic and mechanical properties. [...] Read more.
Cement-slag concrete has become one of the most widely used building materials considering its economical advantage and satisfying uniaxial compressive strength (UCS). In this study, an AI-based method for cement-slag concrete design was developed based on the balance of economic and mechanical properties. Firstly, the hyperparameters of random forest (RF), decision tree (DT), and support vector machine (SVM) were tuned by the beetle antennae search algorithm (BAS). The results of the model evaluation showed the RF with the best prediction effect on the UCS of concrete was selected as the objective function of UCS optimization. Afterward, the objective function of concrete cost optimization was established according to the linear relationship between concrete cost and each mixture. The obtained results showed that the weighted method can be used to construct the multi-objective optimization function of UCS and cost for cement-slag concrete, which is solved by the multi-objective beetle antennae search (MOBAS) algorithm. An optimal concrete mixture ratio can be obtained by Technique for Order Preference by Similarity to Ideal Solution. Considering the current global environment trend of “Net Carbon Zero”, the multi-objective optimization design should be proposed based on the objectives of economy-carbon emission-mechanical properties for future studies. Full article
(This article belongs to the Special Issue Mix-Design and Behavior of Special Concrete)
►▼ Show Figures

Figure 1

20 pages, 20180 KiB  
Article
An Integrated Approach to Using Sheep Wool as a Fibrous Material for Enhancing Strength and Transport Properties of Concrete Composites
by Rayed Alyousef, Hossein Mohammadhosseini, Ahmed Abdel Khalek Ebid and Hisham Alabduljabbar
Materials 2022, 15(5), 1638; https://doi.org/10.3390/ma15051638 - 22 Feb 2022
Cited by 9 | Viewed by 2064
Abstract
An important goal to achieve sustainable development is to use raw materials that are easily recyclable and renewable, locally available, and eco-friendly. Sheep wool, composed of 60% animal protein fibers, 10% fat, 15% moisture, 10% sheep sweat, and 5% contaminants on average, is [...] Read more.
An important goal to achieve sustainable development is to use raw materials that are easily recyclable and renewable, locally available, and eco-friendly. Sheep wool, composed of 60% animal protein fibers, 10% fat, 15% moisture, 10% sheep sweat, and 5% contaminants on average, is an easily recyclable, easily renewable, and environmentally friendly source of raw material. In this study, slump testing, compressive and flexural strengths, ultrasonic pulse velocity, sorptivity, and chloride penetration tests were investigated to assess the influence of wool fibers on the strength and transport properties of concrete composites. Ordinary Portland cement was used to make five concrete mixes incorporating conventional wool fibers (WFs) ranging from 0.5 to 2.5% and a length of 70 mm. The wool fibers were modified (MWFs) via a pre-treatment technique, resulting in five different concrete compositions with the same fiber content. The addition of WF and MWF to fresh concrete mixes resulted in a decrease in slump values. The compressive strength of concrete was reduced when wool fibers were added to the mix. The MWF mixes, however, achieved compressive strength values of more than 30 MPa after a 90-day curing period. Furthermore, by including both WF and MWF, the flexural strength was higher than that of plain concrete. In addition, adding fibers with volume fractions of up to 2% reduced the concrete composite’s sorptivity rate and chloride penetration depths for both WF and MWF content mixes. Consequently, biomass waste like sheep wool could be recycled and returned to the field following the circular economy and waste valorization principles. Full article
(This article belongs to the Special Issue Mix-Design and Behavior of Special Concrete)
►▼ Show Figures

Figure 1

17 pages, 8929 KiB  
Article
Enhanced Acoustic Properties of a Novel Prepacked Aggregates Concrete Reinforced with Waste Polypropylene Fibers
by Rayed Alyousef, Hossein Mohammadhosseini, Ahmed Abdel Khalek Ebid, Hisham Alabduljabbar, Shek Poi Ngian, Ghasan Fahim Huseien and Abdeliazim Mustafa Mohamed
Materials 2022, 15(3), 1173; https://doi.org/10.3390/ma15031173 - 03 Feb 2022
Cited by 6 | Viewed by 1824
Abstract
This research aimed to investigate the performance of prepacked aggregates fiber-reinforced concrete (PAFRC) with adequate acoustic characteristics for various applications. PAFRC is a newly developed concrete made by arranging and packing aggregates and short fibers in predetermined formworks, then inserting a grout mixture [...] Read more.
This research aimed to investigate the performance of prepacked aggregates fiber-reinforced concrete (PAFRC) with adequate acoustic characteristics for various applications. PAFRC is a newly developed concrete made by arranging and packing aggregates and short fibers in predetermined formworks, then inserting a grout mixture into the voids amongst the aggregate particles using a pump or gravity mechanism. After a one-year curing period, the effects of utilizing waste polypropylene (PP) fibers on the strength and acoustic characteristics of PAFRC mixes were examined. Compressive and tensile strengths, ultrasonic pulse velocity (UPV), sound absorption, and transmission loss were investigated on plain concrete and PAFRC mixtures comprising 0–1% PP fibers. The results revealed that the use of PP fibers slightly decreased the compressive strength and UPV of PAFRC mixes. The inclusion of waste PP fibers also significantly increased the tensile strength and sound insulation coefficient of PAFRC mixes, especially at higher fiber dosages. In the medium-to-high frequency ranges, more than 60% acoustic absorption coefficient was observed, indicating that PAFRC specimens have good sound insulation properties. Full article
(This article belongs to the Special Issue Mix-Design and Behavior of Special Concrete)
►▼ Show Figures

Figure 1

18 pages, 7557 KiB  
Article
Effect of Lightweight Aggregate Impregnation on Selected Concrete Properties
by Lucyna Domagała and Agnieszka Podolska
Materials 2022, 15(1), 198; https://doi.org/10.3390/ma15010198 - 28 Dec 2021
Cited by 6 | Viewed by 1338
Abstract
The impregnation of lightweight aggregate (LWA) is an alternative method to its pre-moistening, which is used to limit the loss of fresh concrete workability due to the aggregate’s ability to absorb a great amount of mixing water. The aim of this study was [...] Read more.
The impregnation of lightweight aggregate (LWA) is an alternative method to its pre-moistening, which is used to limit the loss of fresh concrete workability due to the aggregate’s ability to absorb a great amount of mixing water. The aim of this study was to access the effectiveness, by pre-coating LWAs with cement paste, in modifying the properties of concrete composites. Two types of lightweight aggregates (Lytag and Leca) characterized with a relatively open-structure shell were selected. The other changeable parameters taken into consideration in this research were: LWA size, initial moisture of aggregate before the impregnation process and type of cement paste applied as an impregnant. Sixteen concretes prepared with pre-moistened and pre-coated lightweight aggregates were subject to a density test in different moisture conditions, a water absorption test and a compressive strength test. On the one hand, the pre-coating of LWAs with cement paste resulted in a relatively slight increase in concrete density (by up to 19%) compared to the pre-moistening of LWAs. On the other hand, it caused a very significant reduction (by up to 52%) in the composite’s water absorption and an incomparably greater growth (by up to 107%) in compressive strength. The most crucial factors determining the effectiveness of impregnation of LWAs with cement pastes in improvement of composite properties were the aggregate type and its size. The composition of impregnating slurry and the initial moisture content of LWA before pre-coating also mattered. Full article
(This article belongs to the Special Issue Mix-Design and Behavior of Special Concrete)
►▼ Show Figures

Figure 1

23 pages, 8182 KiB  
Article
Recycling Blast Furnace Ferronickel Slag as a Replacement for Paste in Mortar: Formation of Carboaluminate, Reduction of White Portland Cement, and Increase in Strength
by Qingfeng Guan, Jingliang Xia, Jing Wang, Faguang Leng, Yongxiang Zhou and Changwei Cao
Materials 2021, 14(10), 2687; https://doi.org/10.3390/ma14102687 - 20 May 2021
Cited by 3 | Viewed by 2124
Abstract
Blast furnace ferronickel slag (BFFS) is generated in the production of ferronickel alloys and is used as cement replacement in concrete or mortar. The effectivity in reducing cement consumption and improving performance are limited. By referring to the paste replacement method, this work [...] Read more.
Blast furnace ferronickel slag (BFFS) is generated in the production of ferronickel alloys and is used as cement replacement in concrete or mortar. The effectivity in reducing cement consumption and improving performance are limited. By referring to the paste replacement method, this work used BFFS to replace an equal volume of the white Portland cement paste to obtain greater performance enhancement. BFFS was used with five levels of replacement (0%, 5%, 10%, 15%, 20%) and four water-to-cement ratios (0.40, 0.45, 0.50, 0.55) were designed. Fluidity, mechanical strength, hydration products, and pore structure of every mixture were measured. The results showed that the workability of the mortars decreased due to the reduced volume of water, but the 28-day compressive strength of the mortars increased, and the cement content of the mortars was also reduced by 33 wt %. The X-ray diffraction (XRD) patterns revealed that there existed a carboaluminate phase, and the presence of the ettringite was stabilized, indicating that the accumulating amount of the hydration products of the mortar increased. Furthermore, the BFFS could consume the portlandite and free water to form a higher amount of chemically bound water due to its pozzolanic activity. A high degree of hydration and a large volume of the hydration products refined the porosity of the hardened mortars, which explained the enhancement of the strength of the mortars. Compared to the cement replacement method, the paste replacement method was more effective in preparing eco-friendly mortar or concrete by recycling BFFS for reducing the cement content of the mortar while improving its strength. Full article
(This article belongs to the Special Issue Mix-Design and Behavior of Special Concrete)
►▼ Show Figures

Figure 1

15 pages, 6132 KiB  
Article
Influence of The Segregation Phenomenon on Structural Efficiency of Lightweight Aggregate Concretes
by Afonso Miguel Solak, Antonio José Tenza-Abril and Victoria Eugenia García-Vera
Materials 2020, 13(24), 5754; https://doi.org/10.3390/ma13245754 - 16 Dec 2020
Cited by 9 | Viewed by 1951
Abstract
Lightweight aggregate concretes (LWAC) are versatile and interesting materials for projects that require greater structural efficiency. Due to the difference that exists between the densities of the materials used in these types of concrete, during transport and mainly compaction, their aggregates tend to [...] Read more.
Lightweight aggregate concretes (LWAC) are versatile and interesting materials for projects that require greater structural efficiency. Due to the difference that exists between the densities of the materials used in these types of concrete, during transport and mainly compaction, their aggregates tend to separate from the mortar matrix, floating towards the surface, a phenomenon called segregation. Segregation in LWAC can affect its durability properties, its density, and directly affect its structural efficiency. In this work, different concrete densities (1700 kg/m3 and 1900 kg/m3) manufactured with different dosages (two different lightweight aggregates) and compaction methods (one or two layers) were analyzed to verify the impact of segregation on its structural efficiency. For this purpose, the segregation index of the LWAC was obtained by means of the image analysis technique. In addition, to obtain their structural efficiency, the density and compressive strength were obtained at different heights of the tested specimens. The results show the vibration of the samples in two layers leads to a more efficient elimination of trapped air, a reduction in the risk of segregation, and better structural efficiency. Full article
(This article belongs to the Special Issue Mix-Design and Behavior of Special Concrete)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-6
Back to TopTop