Article
Thermodynamics
Christiano Bruneli Peres, Andre Henrique Rosa, Leandro Cardoso de Morais
Summary: The study aimed to measure CO2 capture using carbonaceous materials produced from sugar cane bagasse, showing that chemical activation and heat treatment can yield carbon materials for carbon dioxide adsorption, with impregnated biochar samples demonstrating better adsorption performance.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Geochemistry & Geophysics
Karen L. Scrivener, Ruben Snellings
Summary: This chapter tells the story of Portland cement, from its invention to its development today. The success of Portland cement lies in its abundant raw materials, the reactivity of high-temperature clinker with water, and the properties of the hydration products. However, reducing CO2 emissions remains a major challenge, and options include replacing clinker with low-carbon resources, efficient use of cement and concrete products, and carbon capture and storage or use.
Article
Materials Science, Ceramics
Tamino Hirsch, Zichen Lu, Dietmar Stephan
Summary: The research investigated the hydration of Portland cements with different sulfate carriers in the presence of triethanolamine (TEA), finding that a mixture of sulfate carriers can cause stronger hydration retardation, likely due to rapid formation and depletion of sulfate carriers. TEA was found to disrupt the balance between sulfate carriers and aluminate-containing clinker phases, with the amount and type of sulfate carriers in the cement affecting the TEA-related retardation of hydration.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Construction & Building Technology
Matthias Theobald, Johann Plank
Summary: This study presents the preparation, properties and accelerating performance of three different C-S-H-polycondensate nanocomposites in a fly ash-limestone blended composite cement. The formation of nanofoils via a non-classical nucleation mechanism, their effectiveness as seeding material and accelerator in the early stages of cement hydration, and a slight decline in final strength were observed. The polycondensate-based C-S-H seeds are attractive due to their universal availability, cost-effectiveness and easy preparation method.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Construction & Building Technology
Maciej Zajac, Marc Wieczorek, Barbara Lothenbach, Frank Bullerjahn, Volkmar M. Schmidt, Mohsen Ben Haha
Summary: The study found that the hydration kinetics of cement are influenced by the nucleation, growth, and dissolution rates of hydrates; the concentrations of aluminum and sulfates also play important roles in the reaction rates.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Chemistry, Inorganic & Nuclear
Ya Ling Fan, Hui Ping Zhang, Meng Jia Yin, Rajamani Krishna, Xue Feng Feng, Li Wang, Ming Biao Luo, Feng Luo
Summary: The new metal-organic framework ECUT-77 has a high surface area and pore volume, allowing for efficient adsorption and separation of SO2 gas.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Shiju Joseph, Ozlem Cizer
Summary: This study investigates the effect of Na2SO4 on the mechanical properties, hydration kinetics, and microstructure development of CEM III/B (~69% slag) at low temperatures. The results show that Na2SO4 enhances compressive strength and increases the degree of alite hydration. It also densifies hydrates and reduces porosity.
Article
Chemistry, Inorganic & Nuclear
Wenhui Zhang, Wansheng Jia, Jie Qin, Lan Chen, Youyuan Ran, Rajamani Krishna, Li Wang, Feng Luo
Summary: The emission of sulfur dioxide from flue gases is harmful to human health and the environment. Developing new metal organic frameworks to capture this toxic molecule is important in flue gas desulfurization. The newly synthesized MOF, ECUT-Th-60, exhibits higher uptakes of SO2 compared to CO2 and N-2 under the same conditions, making it promising for the separation of SO2 from gas mixtures.
INORGANIC CHEMISTRY
(2022)
Article
Construction & Building Technology
Naru Kim, Jihoon Park, Issam T. Amr, Jin-Ho Bae, Bandar A. Fadhel, Alam Cho, Siew Ying Tay, Joonho Seo, H. K. Lee
Summary: The study investigated the hydration kinetics of ordinary Portland cement (OPC) mixed under a CO2 inject condition. The effects of different CO2 concentrations or mixing durations under CO2 injection on OPC hydration kinetics were examined. X-ray diffraction analysis and thermogravimetry analysis were used to assess the hydration properties of OPC at an early curing stage. The results showed that high CO2 concentrations and long mixing durations under CO2 injection led to delayed hydration and formation of ettringite, while the flowability decreased and the compressive strength increased.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Chemistry, Inorganic & Nuclear
Wenhui Zhang, Wansheng Jia, Jie Qin, Lan Chen, Youyuan Ran, Rajamani Krishna, Li Wang, Feng Luo
Summary: A new MOF named ECUT-Th-60 was synthesized with high SO2 uptake capacity, showing potential application in flue gas desulfurization.
INORGANIC CHEMISTRY
(2022)
Article
Construction & Building Technology
Ch. Pichler, L. Perfler, R. Lackner
Summary: In this paper, strategies for the deconvolution of the silicate peak and sulfate depletion peak during the hydration kinetics of properly sulfated Portland cements are presented. The boundary nucleation and growth model and the bulk nucleation and growth model are used to analyze calorimetric data. The results show that the boundary nucleation and growth model is suitable for the silicate reaction, while the bulk nucleation and growth model is appropriate for the sulfate depletion peak. The obtained reaction enthalpy for tricalcium silicate hydration is consistent with literature values. The experimental findings are supported by X-ray diffraction analysis of hydration product formation history.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Yu Zhang, Oguzhan copuroglu
Summary: This paper investigated the correlation between the chemistry of slag and the CO2 binding capacity of the blended system. The study found that the hydrotalcite-like phase and calcium carbonate were the main CO2 binding phases, while carbonated Ca-Al AFm phases played a minor role. Additionally, the chemistry of the slag influenced the carbonation degree of the C-S-H gel phase.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Green & Sustainable Science & Technology
Ningbo Gao, Maciej Sliz, Cui Quan, Artur Bieniek, Aneta Magdziarz
Summary: The study found that a 2:1 ratio of N-2 to CO2 at 700 degrees Celsius resulted in a 25% reduction in CO2. The catalytic properties of CaO increased the concentration of H-2 in the produced syngas by up to 10%. However, a temperature of 800 degrees Celsius was too high for the carbonation reaction of CaO.
Article
Construction & Building Technology
Beatriz Goncalves, Caio Exposito, Tomaz Toshimi Ishikawa, Guilherme Yuuki Koga
Summary: This project aims to understand the phase evolution during the hydration of two commercial Portland cements containing carbonate material using X-ray diffraction (XRD). The in-situ technique was compared with the conventional ex-situ method, and it was found that the ex-situ method was suitable for quantifying the contents of constituents and identifying aluminate hydrates. The in-situ approach offered time savings, but had limitations in phase quantification accuracy. The joint use of in-situ and ex-situ techniques can be favorable in an industrial environment, especially in the context of new standards.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Run-Sheng Lin, Yi Han, Xiao-Yong Wang
Summary: This study experimentally investigated and optimized quaternary composite pastes containing limestone, metakaolin, and fly ash. The results showed that with increasing mineral admixtures, the properties such as flow, compressive strength, hydration heat, and CO2 emission decrease, while electrical resistivity is an exponential function. XRD analysis confirmed a synergistic effect between metakaolin, fly ash, and limestone. Multi-objective optimum design is essential for considering strength, workability, ecosystem, thermal performance, and durability in composite paste design.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2021)
Article
Thermodynamics
Jonathan Dias Nascimento, Camila Aparecida Abelha Rocha, Cristina Aiex Simao, Romildo Dias Toledo Filho
Summary: This study focused on the effect of exposing hardened cement slurries to CO2 in water saturation. Results showed that slurries with silica fume presented less calcium carbonate in the internal layers, while mixtures with styrene-butadiene rubber and crystalline silica had higher porosity and permeability, leading to higher carbonation rates.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Thermodynamics
Josinorma Silva de Oliveira, Kuelson Randello Dantas Maciel, Jo Dweck, Heloysa Martins Carvalho Andrade, Jardel Pereira Goncalves
Summary: This study investigates the impact of milling on the properties of a catalyst residue reused in a second FCC process, and finds that milling can improve its reactivity in cementitious pastes.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Chemistry, Physical
Mostafa Galal Aboelkheir, Sabu Thomas, Fernando Gomes de Souza, Romildo Dias Toledo Filho, Roberta Celestino, Sergio Thode Filho, Fernanda Veloso de Carvalho, Fabiola da Silveira Maranhao, Emiliane Daher Pereira, Vitor Correa da Costa, Nathali Ricardo Barbosa de Lima
Summary: This study investigates the use of ground tire rubber (GTR) as a recycled aggregate in concrete for roads or storage areas. Replacing fine aggregate with GTR led to a 56.03% decrease in compressive strength but only a 0.85% increase in water absorption, while impact resistance increased by more than 360%. These results highlight the potential of GTR-modified concrete as a promising recycled aggregate for pavement and structural applications.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Construction & Building Technology
Amanda Pereira Vieira, Romildo Dias Toledo Filho, Luis Marcelo Tavares, Guilherme Chagas Cordeiro
Summary: The effect of particle size and content on the autogenous shrinkage of high-strength concrete was investigated. The results showed that the particle size and the interaction between particle size and RHA content influenced the autogenous shrinkage at 28 and 100 days. The water absorbed internally by the preserved RHA pore structure in the high cement replacement mixes reduced the final autogenous shrinkage of concrete without decreasing compressive strength. Additionally, the RHA with a more preserved pore structure accelerated the hydration kinetics but did not affect the early autogenous shrinkage results.
ADVANCES IN CEMENT RESEARCH
(2022)
Article
Construction & Building Technology
Rayane de Lima Moura Paiva, Lucas Rosse Caldas, Adriana Paiva de Souza Martins, Romildo Dias Toledo Filho
Summary: This research focused on characterizing and evaluating the properties and greenhouse gas emissions of earth-based mortars with bamboo particles. The study found that the mortar with 9% bamboo particles showed a significant improvement in efficiency compared to the one without bamboo, highlighting its potential for the construction industry seeking circular and low-carbon solutions. Additionally, strategies related to Circular economy for reducing GHG emissions of EMB mixtures were proposed.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Chemistry, Physical
Bartosz Zukowski, Yasmim Gabriela dos Santos Mendonca, Igor Jose Koury Tavares, Romildo Dias Toledo Filho
Summary: This study presents an experimental investigation of hybrid cement-based composites reinforced with polyvinyl alcohol fiber (PVA) and alkali-treated, short, natural curaua fiber. The optimal mixture consisted of 1% PVA fiber and 1.5% curaua fiber, exhibiting strain-hardening behavior and crack width control.
Review
Green & Sustainable Science & Technology
Lucas Rosse Caldas, Maykon Vieira Silva, Vitor Pereira Silva, Michele Tereza Marques Carvalho, Romildo Dias Toledo Filho
Summary: This paper conducts a systematic literature review on the application of circular economy in the construction industry, analyzing the roles and integration methods of seven tools. The results show that circular economy strategies mainly involve recycling and the use of recycled materials. Construction workers, researchers, and designers in the industry are the main users of these tools, and it is proposed to further integrate different tools to improve and update them while reducing greenhouse gas emissions.
Article
Construction & Building Technology
Tamara Nunes da C. Moreira, Visar Krelani, Saulo Rocha Ferreira, Liberato Ferrara, Romildo Dias Toledo Filho
Summary: The study shows that sisal fibers enhance the tensile stress and post cracking energy of self-healing concrete specimens, densify the interface, transmit healing agents, and facilitate crack repair.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Green & Sustainable Science & Technology
Lucas Caon Menegatti, Leticia Ikeda Castrillon Fernandez, Lucas Rosse Caldas, Marco Pepe, Francesco Pittau, Giulio Zani, Marco Carlo Rampini, Julien Michels, Romildo Dias Toledo Filho, Enzo Martinelli
Summary: The construction industry is a major contributor to greenhouse gas emissions due to its energy-intensive and raw-material-demanding nature. Making the construction sector greener by recycling construction and demolition waste and optimizing production, assembly, and deconstruction/reuse procedures is crucial. This study evaluates the environmental performance of prefabricated deconstructable and reusable beams incorporating recycled concrete aggregates using a memory steel prestressing technique. Life cycle assessment with a cradle-to-gate approach is used to analyze the environmental impacts, and different allocation scenarios for avoided impacts due to reuse are considered. The study provides design guidelines for circular concrete structures based on the principles of design for deconstruction and prefabrication.
Article
Chemistry, Physical
Alfredo Quiroga Flores, Rodolfo Giacomim Mendes de Andrade, Michele Schubert Pfeil, Joaquim A. O. Barros, Ronaldo Carvalho Battista, Olga Maria Oliveira de Araujo, Ricardo Tadeu Lopes, Romildo Dias Toledo Filho
Summary: This study aimed to investigate the crack propagation behavior of steel fiber-reinforced concrete (SFRC) used in a full-scale prototype of a bridge box girder. The results showed that the peak loads were proportional to the fiber density at the shear failure section. The study also proposed crack-dilatancy and crack width-slip relations based on the shear and flexural test results.
Article
Construction & Building Technology
Mayara Amario, Marco Pepe, Caroline Santana Rangel, Romildo Dias Toledo Filho
Summary: The presence of the Attached Mortar content in recycled concrete aggregates (RCAs) gives them higher porosity and water absorption capacity compared to natural aggregates. Previous studies have focused on the impact of RCAs on the performance of concrete mixtures in fresh and hardened states, while the effects on concrete deformations, such as shrinkage, have been limited. This article presents the results of an experimental study evaluating the influence of RCAs on the autogenous and drying shrinkage of normal and high strength recycled aggregate concrete mixtures. The study found a clear correlation between the intrinsic properties of the RCAs and the resulting concrete deformation.
STRUCTURAL CONCRETE
(2023)
Article
Green & Sustainable Science & Technology
Joaquin Humberto Aquino Rocha, Andreia Arenari de Siqueira, Marco Antonio Barbosa de Oliveira, Lucas da Silva Castro, Lucas Rosse Caldas, Nathalie Barbosa Reis Monteiro, Romildo Dias Toledo Filho
Summary: This study evaluated the use of Acai seed ash (ASA) from the Brazilian Amazon as a replacement for Portland cement in self-leveling mortars. The results showed that using up to 10% ASA as cement replacement was technically and environmentally feasible, reducing greenhouse gas emissions.
Article
Materials Science, Multidisciplinary
Monique Rocha, Bruno Gomes, Amanda Aguiar, Alexandre Landesmann, Nicole Pagan Hasparyk, Romildo Toledo Filho
Summary: Bio-based aggregates are a promising alternative for reducing the environmental impacts of buildings. However, the flammability of these materials is not well understood. This study investigates the fire behavior of bio-based aggregates and finds that alkaline treatment can reduce the heat release rate and heat of combustion, but not the ignition time of these materials.
FIRE AND MATERIALS
(2023)
Article
Construction & Building Technology
Joaquin Humberto Aquino Rocha, Romildo Dias Toledo Filho
Summary: This document provides a critical analysis of the usage of Recycled Concrete Powder (RCP) in the construction industry, specifically as Supplementary Cement Material (SCM). Various treatments, such as grinding, thermal activation, and carbonation, can improve the reactivity of RCP. Additionally, the usage of other SCMs can compensate for the adverse effects of RCP. There are environmental benefits in using RCP, especially in reducing CO2 emissions, but further research is needed to establish its usage.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Energy & Fuels
Maria D. M. Paiva, Romildo Dias Toledo Filho, Luiz Carlos da Silva Nunes
Summary: This study investigates the effect of fiber reinforcement on the tensile behavior of metakaolin-based geopolymers for well applications. The results show that polypropylene fibers can effectively arrest crack growth and improve tensile strength, while wollastonite prevents surface delamination. These reinforced systems are more suitable for downhole applications, as they can withstand greater strains before the formation of continuous cracks and loss of hydraulic isolation.
GEOENERGY SCIENCE AND ENGINEERING
(2023)