Romildo Dias Toledo Filho

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• Professor
• Executive director of the Science Park-UFRJ and Head of the Center for sustainable materials and technologies at Coppe/UFRJ - NUMATS at Federal University of Rio de Janeiro

Nowadays, the construction sector is responsible for a significant part of energy related global carbon emissions. In this context, the wood bio-concrete (WBC) emerges as an environmental-friendly alternative to conventional lightweight concrete by utilizing industry vegetal residues as aggregate, which enhance its energy efficiency. However, due t...

With the ongoing advancement of 3D printing technology in the construction sector, the requirement for materials with optimized fresh and mechanical properties is becoming more critical. Natural fiber-reinforced mortars can be an effective solution by enhancing material's printability. This work evaluates the effect of cellulose microfibers (CF) on...

The increasing focus on sustainable construction has driven interest in 3D printing technology, particularly in developing bio-based cementitious composites that incorporate agricultural by-products. This strategy aims to improve the performance of printable materials while promoting an innovative solution for eco-friendly building practices. In th...

Civil construction is one of the most environmentally impactful industries, accounting for approximately 5% of global carbon dioxide (CO2) emissions, primarily due to the cement production process. To mitigate this impact, it is essential to diversify the materials used in the sector, as the demand for cement is unlikely to decrease significantly....

Provides the state-of-the-art in bio-based building materials Proceedings of the 6th Int'l Conference on Bio-Based Building Materials, Rio de Janeiro, Brazil, 17-20 June 2025 Written by leading experts in the field https://www.dpbolvw.net/click-101461928-12898971?url=https%3A%2F%2Flink.springer.com%2Fbook%2F10.1007%2F978-3-031-92777-5

The development of sustainable and energy-efficient construction materials is crucial for mitigating the growing environmental impact of the building sector. This study introduces a new lightweight sandwich panel, featuring a core made of lightweight concrete with rice husk bio-aggregate (RHB) and faces constructed from foamed cementitious composit...

3D printing with concrete has been accounted as a foremost strategy to mitigate low productivity, workforce shortage, and high waste generation in the construction industry. However, substantial environmental impacts related to high cement content in printable mixtures have received minor concern so far. An interesting prospect is the use of recycl...

Wood bio-based cementitious composite (WBBC) is a promising and eco-friendly construction material which can offer enhanced thermal insulation and reduced environmental impact. This study investigates the influence of wood bio-aggregate content on the thermo-physical and mechanical properties of WBBC. The mixtures were prepared using varying wood s...

Despite significant progress in floating offshore wind turbine (FOWT) technology, there are still several challenges, including the design of a cost-effective system. Considerable research has been dedicated to optimizing the floating platform geometry, layout, dimensions, and weight over the past few years, with some focusing on semisubmersible pl...

The direct method of determining bulk electrical resistivity (BER) is as a valuable standard for assessing the corrosion risks in concrete structures. However, the electrical resistivity is highly sensitive to the moisture content of the concrete, and the conditions of the cores extracted from the structure, such as their dimensions and level of cr...

The management of glass waste presents a challenge in the construction sector, and its integration into concrete offers an innovative approach to waste valorization and sustainable materials development. This study explores the novel use of fine glass waste (FGW) as a mineral admixture, evaluating its impact on mechanical performance and durability...

The construction industry’s pursuit of eco-friendly materials has sparked interest in bamboo, a renewable resource with exceptional physical and mechanical properties. This study analyzed the integration of Dendrocalamus giganteus bamboo with phase change materials (PCMs) to enhance thermal energy storage in building applications, aiming to improve...

The escalating demand for sustainable and energy-efficient buildings has driven research into innovative construction materials such as bio-concrete. This study assesses the influence of bio-aggregates such as bamboo particles, wood shavings, and rice husk in volume ranging from 40 % to 50 % on bio-concrete's physical and hygrothermal properties. T...

The Cactaceae family is a suitable alternative for future sustainable development in the construction industry. In addition to being a renewable raw material, these plants grow with ease and are extremely adaptable to the most diverse and rigorous climates and poor soil. The Cereus jamacaru DC. has a woody structure that is unknown and, consequentl...

This study investigates the incorporation of fine bamboo particles, typically discarded, into cementitious matrices as bio-aggregates for bioconcretes. During the crushing process of bamboo culms, particles of various sizes are produced, with up to 13% of the volume consisting of fine particles. The aim is to characterize the physical and mechanica...

The search for solutions that reduce the environmental impact of construction has driven the development of new materials. Bio-concrete represents a significant advance, presenting itself as an alternative to traditional concrete. Recent studies point to durability in outdoor conditions as one of the main challenges in its application. This paper p...

Reinforcement of cement-based systems is one of the main unsolved issues for 3D printing technology (3DP). The use of short fibers is a promising way to improve cement-based systems fresh and hardened strength, overcoming this limitation. Among natural fibers, Sisal fibers (SF) can be an excellent option, due to their irregular cross-section morpho...

Reinforced concrete (RC) structures are widely used in engineering due to their physical, chemical and mechanical characteristics that guarantee good durability. However, one of the main mechanisms of degradation of these structures is associated with the corrosion of the reinforcement, which often occurs due to carbonation of the concrete and/or t...

The present work investigates the impact of particle size reduction of traditional ceramic materials as partial substitutes for Portland cement in mortars. Ceramic brick, ceramic tile, and stoneware were selected, with three particle sizes (D50 of 1, 5, and 15 μm) achieved through grinding operations adapted to each material grindability. The react...

Despite significant progress in floating offshore wind turbine (FOWT) technology , there are still several challenges, including the design of a cost-effective system. Considerable research has been dedicated to optimizing the floating platform geometry, layout, dimensions, and weight over the past few years, with some focusing on semisubmersible p...

The industrial revolution altered the way resources are consumed, primarily increasing the intensity of extraction with a tendency to exhaust natural reserves. It is necessary to replace artificial materials and those derived from non-renewable sources with biomaterials, particularly those characterized as waste from productive activities. In this...

3D printing mortars are becoming a focus of interest for architectural applications , due to their ability to produce free shaping designs. However, there are still some printability and performance issues that require further research , as the incorporation of reinforcing and the improvement of sustainability by reducing its carbon footprint. Natu...

3D Printing in construction hold great opportunities to tackle long-lasting challenges such as high waste generation and lack of automatization. However limited solutions to lower the high cement content of printable mixtures have been proposed. An interesting prospect is the use of recycled concrete powders (RCP) as cement replacement. RCPs are co...

O grande crescimento da demanda por energia renovável nos últimos anos tem representado um desafio à engenharia estrutural pela necessidade de estruturas maiores e mais esbeltas para aumento da capacidade de geração. Demandas de mercado tem resultado na substituição de torres e plataformas em aço por estruturas de concreto armado, que podem incorpo...

Nowadays, wood bio-concrete (WBC) can be seen as an alternative to reduce environmental impacts of the construction industry. The behavior of this material under fire conditions, however, is still poorly understood. In this sense, this work aims to investigate the behavior of wood bio-concrete under fire conditions. In this study, the wood shavings...

O objetivo do presente estudo foi avaliar a influência da substituição do cimento Portland (CP) por metacaulim (MC) e pó de concreto reciclado (PCR) na resistência à compressão de argamassas e concretos. Foram propostas misturas de argamassa e concreto com resistências à compressão de 15 e 50 MPa, substituindo 5 e 20% de CP por MC e PCR. Os materia...

The retrofitting process contributes to the sustainability of the construction sector, since adopting measures to increase the lifespan of buildings reduces the need for new constructions. However, many of the materials used in this process come from nonrenewable sources and require significant water and energy consumption for production. The aim o...

This paper presents a method for designing low carbon bio-based building materials, also named bio-concretes, produced with wood wastes in shavings form (WS) and cementitious pastes. As the aggregates phase of bio-concretes is composed of plant-based particles, known as porous and high water-absorbing materials, the bio-concretes cannot be designed...

Large structures need to be monitored to ensure safety for users and increase their service life through predictive maintenance. Self-sensing cementitious composites have been studied for structural health monitoring applications. By adding carbon nanotubes (CNTs) to a cement matrix, the resulting composite exhibits piezoresistive properties, makin...

This research aimed to enhance the impregnation of carboxylate styrene butadiene rubber (XSBR) polymer on jute yarns, thereby improving the mechanical properties of textile-reinforced cementitious composite (TRCC). An experimental investigation on the use of cellulose microcrystals and nanofibrils as additives to XSBR admixture was conducted. Four...

Portland cement is one of the most used construction materials. However, its production represents between 5 and 7% of the total CO2 emissions. On the other hand, during construction and demolition activities, different wastes are produced, including recycled brick powder (RBP), whose potential as a supplementary cementitious material (SCM) has bee...

An electrically conductive filler can be mixed into a cement-based matrix to create a self-sensing cementitious composites (SSCC). Carbon-based materials, such as graphene, carbon fiber, and carbon nanotubes (CNT), are the most commonly used fillers for this purpose. Concrete structures can be monitored through the changes in the SSCC electrical re...

The use of fabric in reinforcing cement-based materials expands their applications for various types of construction elements. Additionally, employing renewable sources of plant-based fabrics contributes to reducing the environmental impact of the construction industry. However, the variability in the properties of plant fibers and fabrics necessit...

Wood bio-concrete is a sustainable alternative for civil construction as it combines the use of wood residual shavings as bio-aggregate and partially replacement of cement by supplementary cementitious materials (SCMs) of low environmental impact. However, its partially organic nature promotes to the bio-concrete a higher water absorption capacity...

This paper presents a study on the application of crushed bamboo powder as a thixotropic agent in cement-based composites for three-dimensional printing. The thermal degradation and composition of the bamboo powder were analyzed using thermogravimetric analysis. Porosity and shape of the powder were evaluated using Scanning Electron Microscopy. The...

Construction is one of the industries with the greatest environmental impact in the world, highlighting the emission of CO2 and the generation of waste. In this sense, reducing, reusing, and recycling materials is a sustainable alternative to mitigate this problem. This study aims to evaluate the use of Recycled Concrete Powder (RCP) as a substitut...

This study aims to evaluate the effect of RCP from a precast concrete plant on rheological and mechanical properties of cementitious pastes. In the study, Portland cement was replaced by RCP in 10, 20, and 30% (in mass). The hydration kinects of cement with RCP was studied through isothermal calorimetry. The fresh properties were assessed using min...

O objetivo desta pesquisa foi estudar a influência dos resíduos do arroz (casca e cinza da casca) nas propriedades físicas, mecânicas e térmica de biocompósitos contendo cimento Portland, a fim destinar os resíduos e reduzir o impacto ambiental do descarte inadequado, além de reduzir a extração de recursos naturais pela construção civil. Os biocomp...

O Bioconcreto é um material compósito formado por uma matriz cimentícia que aglutina partículas de biomassa vegetal utilizadas como bio-agregados. O bambu, entre outras aplicações, pode ser utilizado como bio-agregado, o que confere ao material produzido leveza, baixa condutividade térmica e menor pegada de carbono. No entanto, devido ao fato de se...

Understanding cement shrinkage behavior in offshore well cement sheaths is crucial for assessing integrity and preventing potential issues. This study investigates the correlation between early strength development and shrinkage to assist in cement paste design. In this research, one cement paste was formulated with water-to-cement ratio of 0.36 an...

The objective of this work is to characterize the alteration on cement pastes exposed to 30+ years of natural ageing at downhole conditions. The cement samples used in this study were recovered from two production wells drilled in the Norwegian continental shelf completed in the late 1980's. Sandwich sections comprised of an inner and outer casing...

Environmental issues have led to the use of biomass wastes in making cement-bonded construction materials to improve their thermal insulation, and thus build energy-efficient performance. However, the use of biomass in bio-concrete is a cause of concern from the point of view of an accidental fire. Therefore, the present study aims to provide an ov...

This study presents the results of a wide experimental campaign aimed at characterizing the physical and mechanical response of sustainable cementitious composites produced different types of bio-aggregates (i.e., bamboo particles, wood shavings and rice husk). First of all, based on the specific physical and geometrical properties of the bio-aggre...

Bio-based materials, such as wood bio-concrete (WBC), hold promise in reducing energy consumption and carbon footprint of the construction industry. However, the durability of these materials is not well understood and can be negatively affected by the high water absorption capacity of wood bio-aggregates. In the field of cement composites, for exa...

O presente estudo tem como objetivo realizar uma Revisão Sistemática da Literatura (RSL) sobre a avaliação dos impactos ambientais por decorrentes do uso de Materiais Cimentícios Suplementares (MCS) e Agregado Reciclado (AR) em materiais de construção, por meio da metodologia de Avaliação do Ciclo de Vida (ACV). A metodologia consistiu na busca de...

Bio-based aggregates can be seen as one of the promising alternatives to reduce the environmental impacts of buildings due to their lower carbon footprint and energy efficiency. They have great potential to be incorporated into inorganic matrices and produce insulating materials. However, there is a lack of information about the flammability of the...

Wood bio-concrete is a promising bio-based building material due to its insulating properties and its contribution to increase energy efficiency and reduce environmental impacts. However, there is still a lack of knowledge concerning its durability over time. For that reason, this study investigates the influence of accelerated aging in laboratory...

Two main challenges of the construction and building sector are improving energy efficiency and reducing embodied environmental impacts. Low carbon products incorporating bio-based and waste materials are essential to reduce Greenhouse Gas (GHG) emissions from buildings’ whole life-cycle. In this context, bio-concretes can be considered innovative...

Studies on bio-based building materials are promising due to their insulating characteristics, low density and good hygrothermal performance. However, range of factors can influence its durability, including biological processes. For that reason, this study investigates the susceptibility to the growth of microorganisms in bamboo bio-concretes (BBC...

This paper presents an experimental campaign and a numerical model that describe a potential application of magnetic nanoparticles (MNP) in oil well cementing pastes. MNP, when subjected to an oscillating magnetic field, can generate a heating effect, which accelerates the cement hydration reaction through thermal activation. This, in turn, reduces...

Literature reports indicate that Carbon Nanotubes (CNT) are one of the best conductive fillers for self-sensing cementitious composites (SSCC) due to their excellent electrical conductivity. However, due to their Van der Waals interactions and hydrophobic nature, it is a challenge to properly disperse them throughout the cement matrix. Among the kn...

This research aimed to improve the impregnation of XSBR (Carboxylate Styrene Butadiene Rubber) polymer on jute yarns, and hence the mechanical properties of a TRCC (Textile-Reinforced Cementitious Composite). Thus, an experimental investigation on the use of microcrystalline and nanofibrillated cellulose as additives to XSBR admixture was carried o...

O setor da construção tem se tornado um dos grandes motivos de preocupação ambiental, principalmente quando se trata da emissão de dióxido de carbono e geração de resíduos. Uma forma de mitigar tais impactos consiste na substituição de um sistema linear para um modelo de Economia Circular (EC). Nesse modelo, a reciclagem de Resíduos de Construção e...

The reuse of Construction and Demolition Waste (CDW) to produce new materials is an effective method for reducing the negative impacts from the inadequate waste disposition, in addition to bringing economic and environmental benefits to the industry. The use of Recycled Concrete Aggregate (RCA) in concrete is a technique widely disseminated, howeve...

An alternative way to mitigate the impact generated by the Construction and Demolition Waste (CDW) on the environment is recycling this material in order to utilize it as Recycled Concrete Aggregates (RCA) in concrete. Studies carried out demonstrated that while using a scientific mix-design, it is possible to have a Recycled Aggregate Concrete (RA...

Seeking the development of light structural elements with less environmental impact, the use of bamboo strips as bio-concretes reinforcement can provide an interesting solution in civil construction. Therefore, in order to use the bamboo strip with bio-concrete, it is important to understand the bond-behavior between both materials. This paper aims...

The growing global energy demand requires solutions that improve energy efficiency in all sectors. The civil construction sector is responsible for a large part of global energy consumption. In this context, phase change materials (PCMs) can be incorporated into construction materials to improve the energy efficiency of buildings. The purpose of th...

This experimental research aims to produce rice husk bio-concretes (RBCs) with a matrix of ternary mixtures of cement, rice husk ash and fly ash. The first step consisted in an evaluation of the influence of a superplasticizer additive and a polyfunctional additive on the rheological behavior of cementitious pastes. The purpose of this step was to...

No contexto das novas tecnologias que o setor da construção civil emprega para minimizar as emissões de gases de efeito estufa, os bioconcretos surgem como uma alternativa promissora, pela sua baixa pegada de carbono. Dentre os diversos bioagregados (BB) disponíveis para tal uso, a partícula de bambu desponta como uma relevante opção, por se tratar...

O uso de materiais de origem vegetal na produção de compósitos cimentícios é uma solução que vem sendo desenvolvida para o avanço da construção com menores impactos ambientais. Bioconcretos produzidos com resíduos de madeira apresentam baixa densidade, melhoram a eficiência energética de uma edificação e são capazes de armazenar CO2. Para determina...

Esta pesquisa apresenta um estudo da atuação do pó de borracha de pneu sobre as caracteristicas reológicas e mecânicas de pastas de cimento, mediante a substituições volumétricas pelo agregado fino, sílica 120 mesh. As pastas foram caracterizadas no estado fresco pelas técnicas de massa específica aparente, ar aprisionado, e reologia, e, no estado...

The high emissions of carbon dioxide and the concern with environmental issues have led to greater use of lignocellulosic biomass in civil construction, especially wood. The incorporation of wood bio-aggregates in cementitious composites allows the development of an energy efficient material, having its thermal insulating and carbon sequestration c...

Resumo A utilização de bio-agregados de madeira para a produção de bioconcreto tem mostrado elevado potencial para o desenvolvimento de materiais com baixo impacto ambiental, uma vez que estes armazenam carbono biogênico. Entretanto, o elevado consumo de cimento é responsável por emissões significativas de carbono na atmosfera. Portanto, este estud...

Resumo O bioconcreto de bambu (BCB) é um material compósito, onde os agregados são partículas de bambu incorporados a uma matriz cimentícia, que se mostra como uma atrativa alternativa para o setor da construção devido sua menor pegada de carbono e eficiência energética quando aplicado em edificações. Contudo, se faz necessário avaliar o comportame...

The main relevant difference between recycled concrete aggregates (RCAs) in comparison with the companion natural ones, is the presence of the Attached Mortar content which confers to the RCAs higher porosity and, consequently, higher water absorption capacity. In the last decades, several studies have been performed worldwide for unveiling the rol...

Experimental research on the direct shear behavior of fiber-reinforced concrete is often carried out using prisms molded with specific dimensions for a standardized test. However, the flow of fresh concrete in these molds can be different than in the case of a full-scale structural element. This is important considering that the flow direction high...

Circular Economy (CE) is progressively attracting interest from construction sector stakeholders to support the development of products with higher amounts of recovered materials in order to decrease greenhouse gas (GHG) emissions. Concrete is one of the most used materials in the world and can be produced using waste as raw materials, including, b...

Açaí seed ash (ASA) is a waste product from processing the açaí fruit and burning the seeds for cogeneration purposes. The present study evaluated the use of ASA from the Brazilian Amazon as partial Portland cement replacement in self-leveling mortars (SLM) for social-interest buildings. The fresh and hardened state properties of mortars were acces...

Phase change materials (PCMs) are functional materials that can absorb thermal energy in latent heat. Among these, the environmentally-friendly Bio-PCMs, obtained from renewable sources, have drawn the attention of researchers because of its advantages. This work aimed to produce a Bio-PCM based on oligo (butyl succinate) with the lowest melting te...

The main objective of this research was to investigate and discuss the interaction between Eucalyptus sp. cellulose nanofibrils (CNFs) and carboxylated styrene–butadiene rubber (XSBR) to produce composite films with higher deformation capacity. The studied films were evaluated through mechanical, morphological, chemical, and physical analysis. The...

Resumo Nos últimos anos, a impressão 3D de concreto vem ganhando cada vez mais espaço, devido a diversas vantagens que a tecnologia possui frente a métodos tracionais de construção, como maior produtividade e menor geração de resíduos. Na dosagem dos materiais para impressão 3D, as propriedades reológicas desempenham um papel fundamental, sendo imp...

A norma de desempenho de edificações habitacionais NBR 15575:2013, estabelece exigências de qualidade para imóveis em aspectos como acústica, iluminação e temperatura. Um dos tópicos abordados pela norma exige que a temperatura interna de cômodos de permanência prolongada (salas e quartos) seja igual ou menor a temperatura no exterior do imóvel. Co...

Resumo O uso cada vez mais frequente de alternativas de menor impacto ambiental dentro do setor da construção civil faz com que os cientistas busquem otimizar os materiais existentes ou propor soluções que usem materiais com menor impacto ambiental. Uma das possibilidades é a incorporação de agregados de origem vegetal na matriz cimentícia para pro...

The environmental and mechanical performance of bamboo culms and strips for their use in construction are evaluated considering two species: Moso (Phyllostachys pubescens) and Dendrocalamus giganteus. Life Cycle Assessment (LCA) was used for the environmental performance assessment. For the mechanical performance evaluation , the following tests we...

The construction sector is one of the most energy-intensive and raw-material-demanding human activities and, hence, contributes a significant share of greenhouse gas emissions. As a matter of principle, making the construction sector “greener” is one of the main challenges for policy makers, private companies and the scientific community. For this...

The reuse and recycle of mining tailings are alternatives that could reduce the environmental impact related to its destination, and, also, promote sustainable development. The incorporation of mining tailings in pavement layers, such as base, subbase, and subgrade, has the potential to reduce the consumption of natural resources and to promote a n...