Antonio A. Melo Neto

• Doctor
• Professor (Associate) at Federal University of Pernambuco

Alkali-activated slag concrete is attracting increasing attention because of its potential as an alternative to Portland cement concrete, and it has been studied in several countries. The development of high-strength alkali-activated Portland-cement-free concrete, made with ground granulated blast furnace slag and sodium silicate solution as the bi...

Activated slag cement (ASC) shows significantly higher shrinkage than ordinary Portland cement agglomerates. Cracking generated by shrinkage is one of the most critical drawbacks for broader applications of this promising alternative binder. This article investigates the relationship between ASC hydration, unrestrained drying and autogenous shrinka...

This paper proposed to assay the pozzolanic activity of different types of sugarcane bagasse ash (SBA) using the X-ray powder diffraction technique. The as-received SBA presented a high loss on ignition and a coarse particle size, and then, the processing employed calcination and grinding. Pastes and mortars formed with SBA and calcium hydroxide we...

This article reports the characteristics of blast furnace slag (BFS) pastes activated with hydrated lime (5%) and hydrated lime (2%) plus gypsum (6%) in relation to compressive strength, shrinkage (autogenous and drying) and microstructure (porosity, hydrated products). The paste mixtures were characterized using powder X-ray diffraction (XRD), mer...

This study investigates the influence of cement-based spacers, including site-produced (SSPO) and industrially manufactured (SSIM), on reinforcement corrosion in concrete exposed to chloride ions and accelerated carbonation. Prismatic specimens with a nominal 2.5 cm cover were tested. SSPO spacers exceeded the specified thickness but showed high di...

O lodo têxtil é o resíduo sólido produzido após o tratamento dos efluentes líquidos produzidos nas lavanderias industriais. Buscou-se analisar o comportamento mecânico de argamassas incorporadas com lodo em substituição parcial ao agregado miúdo nos teores de 0, 10%, 20% e 25%, sob o traço 1:1:6, em cimento, cal e areia. Foram realizados os ensaios...

Textile sludge is a solid waste generated by the textile industry as a byproduct of effluent treatment, and its improper disposal poses environmental risks. Therefore, it is crucial to explore alternative reuse strategies for this waste. In contrast to previous studies that primarily utilized raw textile sludge, this work systematically evaluates t...

A fachada de uma edificação é mais do que uma simples barreira física que separa o interior do exterior. O revestimento da fachada é responsável pela expressão estética do edifício, mas também desempenha um papel crítico acerca da segurança contra incêndios, conforto termoacústico, eficiência energética e durabilidade. Os painéis de material de alu...

A presente investigação tem como ponto de partida a problemática do lodo têxtil, principal resíduo sólido gerado pela indústria têxtil no processo de tratamento de efluentes. Frequentemente, este material não recebe destinação adequada, tornando crucial a busca por alternativas para o seu reaproveitamento. Nesse contexto, este estudo avalia as inte...

A problemática do resíduo de caulim gera desafios ambientais e socioeconômicos devido à destinação inadequada, pois esse subproduto do beneficiamento pode contaminar solo e água, impactando comunidades locais. Soluções sustentáveis, como tecnologias de reaproveitamento, são essenciais para equilibrar os impactos econômicos e ambientais na região. E...

A escória de alto forno destaca-se como uma alternativa sustentável na indústria do cimento. No entanto, cimentos com elevados teores de escória não apresentaram elevada resistência inicial. Com isso, surge o cimento híbrido álcali ativado que é resultante da combinação entre cimento Portland, escória de alto forno e um ativador alcalino. Nesta pes...

O cimento Portland é o material mais utilizado na construção civil. Estima-se que o processo de produção do cimento seja responsável por 5% das emissões de CO2 do planeta. Diante disto, pesquisas vêm sendo realizadas com cimentos híbridos álcali ativados no intuito de produzir aglomerantes de menor impacto ambiental. Em razão de poucos estudos rela...

O concreto celular é valorizado por sua estrutura porosa, obtida pela incorporação de espuma à matriz cimentícia. No entanto, a tendência das bolhas de se unirem e colapsarem durante a preparação apresenta desafios para a produção e controle das propriedades dessas estruturas. Em busca de soluções mais sustentáveis, a escória de alto forno ativa...

Este estudo investiga a possibilidade de utilizar o Lodo Têxtil (LOTex) como material cimentício suplementar, visando mitigar o impacto ambiental e melhorar a gestão de resíduos no setor têxtil. O LOTex foi beneficiado com moagem e calcinação para aumentar sua reatividade pozolânica, com diferentes temperaturas de calcinação (600°C, 700°C e 800°C)....

O Brasil é um dos maiores produtores de materiais têxteis do mundo, setor fortemente ligado a geração de efluentes e de resíduos sólidos, como o lodo têxtil. O objetivo foi de avaliar o comportamento físico de argamassas de revestimento de traço 1:1:6, em cimento, cal e areia, com substituição parcial do agregado miúdo por lodo têxtil nos teores de...

The proper management of construction and demolition waste (CDW) from the construction industry is an issue that has gained relevance over the last years and, in this context, research on the potential of using CDW in concrete construction has stood out. This work analysed the durability of concrete with CDW when exposed to aggressive agents. Prism...

This article presents a research done with Military Firemen who have passed through a three-week intensive firefighting training. Developed by the authors, it was applied an air consumption measurement protocol during the use of the self-contained breathing apparatus (SCBA), fundamental firefighting equipment, before and after that period. It was n...

A R T I C L E I N F O Keywords: Sugarcane bagasse ash Alkali-activated binder Sodium metasilicate Scanning electronic microscopy One-part binder A B S T R A C T This study aimed to develop eco-friendly alkali-activated mixtures utilizing blast furnace slag (BFS) and un-ground sugarcane bagasse ash (SBA). One-part mixtures comprising BFS, SBA, and s...

This paper evaluates the potential of water treatment sludge ash (WTSA) as high-reactivity pozzolan using strength tests in mortars and techniques to evaluate the calcium hydroxide consumption in pastes with hydrated lime. The sample was dried in an oven and then calcined at 600, 700, and 800 ◦C in a muffle. A high-reactivity metakaolin sample was...

Fenton-type advanced oxidative processes (AOP) have been employed to treat textile dyes in aqueous solution and industrial effluent. The work focused on assisting the limitations still presented by the Fenton process regarding the use of suspended iron catalysts. Soon, a nanocomposite of bacterial cellulose (BC) and magnetite (Fe3O4) was developed....

Foam concrete stands out among special concrete for presenting a porous structure by incorporating foam into the cement matrix. The tendency for bubbles to coalesce and collapse during preparation poses some challenges in production and control over the properties of cell structures. This research aims to evaluate the behavior of cellular concrete...

This article evaluates the influence of Na2O concentration from sodium silicate and metasilicate activators on the physical, mechanical, and chemical/mineralogical properties of blast furnace slag alkali-activated mixtures. The mixtures were prepared with Na2O dosages of 3, 4.5, 6, and 7.5%. Compressive strength results showed that the maximum valu...

The presence of pharmaceutical compounds has been increasingly frequent in aquatic matrices. This is due to the low efficiency of treatment plants against these compounds. Therefore, in this work, the efficiency of the treatment via heterogeneous photo-Fenton process was studied, containing a mixture of the drugs atenolol and propranolol, in two ma...

In this work, the advanced oxidation technology was investigated through the degradation of a solution composed of four textile dyes, more complex than the solutions used in similar researches. For this purpose, heterogeneous photo-Fenton process was applied, using the mineral pyrite as iron catalyst and sunlight as a radiation source. This researc...

p class="Normal1"> Este trabalho tem o objetivo de analisar a influência da incorporação da cinza do bagaço da cana na resistência à compressão de misturas secas de concreto, visando sua utilização em pavimentos intertravados. A caracterização física e química da cinza foi feita por meio de ensaios de massa específica e finura Blaine, fluorescência...

Among the short-term viable alternatives for mitigating the direct emissions of carbon dioxide into the atmosphere by the cement industry, the partial replacement of Portland clinker or cement with supplementary cementitious materials (SCM) is the most efficient and conceives ecologically friendly binders. Limitations of available traditional SCMs...

With better deformation capacity and less resistance than conventional concrete, cellular concrete with expanded polystyrene (EPS) is a more suitable alternative for obtaining concrete with a low specific mass. Since the late 1980s, alkali-activated slag concrete (AASC) without Portland cement has been gaining attention. However, no comprehensive s...

This work proposed to incorporate the sugarcane bagasse ash (SBA) with a high content of organic matter (loss on ignition of 35.87%) in alkali-activated mixtures with blast furnace slag. After grinding SBA, replacement ratios of 10%, 20%, and 30% of the ground ash were used for the flowability evaluation. The mixtures containing 20% and 30% showed...

The solution mixture of the non-steroidal anti-inflammatory drugs ketoprofen, meloxicam and tenoxicam were degraded through of systems, composed of different photocatalyst based on TiO2 (Fe and Cu) and the hydrogen peroxide oxidant. The monitoring was performed by UV-Vis spectroscopy. Under sunlight radiation, a reduction in peaks was observed with...

A velocidade de crescimento das cidades e o ritmo acelerado de produção e consumo de materiais levantam a problemática a respeito da exploração e limitação dos recursos naturais. Neste contexto, a utilização de agregados reciclados provenientes de resíduos de construção e demolição (RCD), em substituição aos agregados naturais, tanto em concretos q...

This work evaluates mortars using sewage sludge calcined at temperatures of 600°C and 700°C as a hydraulic binder replacing the cement. The percentages incorporated by mass to replace the Portland cement were 10%, 20% and 30%, using the 1:3:0,60 (cement: sand: factor a/c) trace. Sludge ash was characterized and tensile strength at flexion as well a...

Urbanization and continuing population and industrial growth have led to the intensification of management issues related to residues of wastewater treatment. To reduce sludge storage and carbon dioxide emissions resulting from Portland cement production, the pozzolanic activity of sewage sludge ash (SSA) was studied as a supplementary cementitious...

RESUMO É crescente o reaproveitamento e utilização de resíduos em matrizes de base cimentícia, no intuito de um destino adequado, por apresentarem propriedades pozolânicas, bem como, na perspectiva da redução do consumo de cimento Portland. Neste trabalho foram produzidas cinzas a partir do beneficiamento de moagem da cinza do bagaço de cana-de-açú...

A urbanização e o constante crescimento populacional e industrial ocasionou um problema no gerenciamento dos resíduos provenientes do tratamento de esgoto. No Brasil, as baixas taxas de coleta e tratamento de esgoto indicam que ainda existe um grande potencial de crescimento na quantidade de material a ser produzido, sendo disposto, principalmente,...

This paper presents an experimental program objectifying at investigating the potential of the use of sugarcane bagasse ash as a partial replacement of cement in the production of mortars. Sugarcane bagasse ashes from two origins were studied - one from sugarcane industry directly and other from pizzerias that uses this material replacing the wood...

RESUMO Esse artigo verificou as propriedades dos agregados de RCC reciclados na utilização em concretos e comparou as principais especificações das normas estrangeiras frente a brasileira NBR15116 (2004). Realizou-se uma revisão bibliográfica em pesquisas e nas proposições normativas. Parâmetros físicos, químicos, geométricos e mecânicos são solici...

The aim of this paper is to present a proposal for the recycling of construction and demolition waste (CDW) at construction sites and the use of recycled sand in bedding mortar. Three samples of CDW were collected at construction sites from the city of Recife, Brazil and milled in a hammer mill. The following properties of the recycled sands were a...

COMPARATIVE ANALYSIS BETWEEN METHODS OF DETERMINATION OF WATER ABSORPTION IN fFINE RECYCLED AGGREGATE: NM 30 x DRYING MICROWAVE In Brazil, the method used to measure the water absorption of fine aggregates is the NM 30, which was originally conceived to characterize natural aggregates, not being suitable for recycled aggregates from construction an...

The purpose of this work is verifying the influence of calcination temperature of sugar cane bagasse ash (SCBA) in the pozzolanic activity with lime (IAC), according to Brazilian standard NBR 5751. The SCBA is an important residue of the northeast region and the State of Pernambuco, however their disposal still a problem. The ash used is coming fro...

This article reports on the investigation of the relation between the activated blast-furnace slag cement hydration and unrestrained autogenous shrinkage development on mortar specimens. The chemical and microstructure changes due to hydration were determined on pastes by conduction calorimetry, mercury porosimetry and thermogravimetric analysis. S...

Resumo Este trabalho tem como objetivo estudar o comportamento e adequação do diagrama de dosagem do concreto com relação a uma propriedade específica, o módulo de elasticidade. Assim como a adequação de alguns modelos de previsão do módulo de elasticidade baseados na resistência à compressão. Foram produzidos cinco traços diferentes: inicialmente...

Resumo Este trabalho tem como objetivo estudar o efeito do aditivo redutor de retração (SRA) no desenvolvimento da retração por secagem e na retração autógena em argamassas confeccionadas com cimento Portland de alta resistência inicial (ARI). Os corpos-de-prova foram preparados com a relação água/aglomerante igual a 0,48 e com quatro teores de adi...