This page has only limited features, please log in for full access.

Dr. João Delgado
CONSTRUCT, Department of Civil Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal

Basic Info


Research Keywords & Expertise

0 Energy Storage
0 Fluid Mechanics
0 Mathematical Modeling
0 Wastewater Treatment
0 Composite materials

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 27 July 2021 in Materials
Reads 0
Downloads 0

The understanding of the mechanical fixation behavior of coatings is crucial for a better comprehension of the bonding systems, especially at the interface between the mortar and the substrate. Physical adherence is related, among other things, to the contents of the materials used in the roughcast and mortar coatings, due to the colloidal water penetration into the pores of the substrate. This work evaluated the influence of different lime solution additions replacing the kneading water in the preparation of roughcast and mortar coatings. Two types of substrates were investigated:ceramic bricks and concrete blocks. Three wall masonry panels were constructed, with dimensions of 220 × 180 cm2, one of concrete block and two of ceramic bricks, followed by the application of roughcast and mortar coating with an average thickness of 5 mm and 20 mm, respectively. Direct tensile bond strength tests were performed and the results, with a 95% confidence level, showed that substrate ceramic and treatment in the roughcast exhibited a better behavior regarding the distribution of the tensile bond strength of the tested specimens. However, no significant differences of the amount of addition used (0%, 5%, 10% and 15%) on the tensile bond strength were observed.

ACS Style

André Santos; Ângelo Silva; João Mota; João Delgado; Fernando Silva; António Azevedo. The Influence of Lime Solution in Kneading Water Substitution on Cement Roughcast and Mortar Coating. Materials 2021, 14, 4174 .

AMA Style

André Santos, Ângelo Silva, João Mota, João Delgado, Fernando Silva, António Azevedo. The Influence of Lime Solution in Kneading Water Substitution on Cement Roughcast and Mortar Coating. Materials. 2021; 14 (15):4174.

Chicago/Turabian Style

André Santos; Ângelo Silva; João Mota; João Delgado; Fernando Silva; António Azevedo. 2021. "The Influence of Lime Solution in Kneading Water Substitution on Cement Roughcast and Mortar Coating." Materials 14, no. 15: 4174.

Journal article
Published: 24 July 2021 in Energies
Reads 0
Downloads 0

The main goal of this work is the analysis of potential energy and green benefits of 3D printing on building construction. Current literature reports a considerable number of benefits for 3D printing, namely, reduction of material use, lower operational costs and time-saving. The authors also mention design freedom, higher efficiency, productivity and quality. This work presents the latest developments in 3D printing in civil engineering, namely, a review of the last 3D printing projects and the limitations of construction 3D printing with a focus on large-scale applications, technology costs, mix development and optimisation and thermal behaviour.

ACS Style

Ana Guimarães; João Delgado; Sandra Lucas. Advanced Manufacturing in Civil Engineering. Energies 2021, 14, 4474 .

AMA Style

Ana Guimarães, João Delgado, Sandra Lucas. Advanced Manufacturing in Civil Engineering. Energies. 2021; 14 (15):4474.

Chicago/Turabian Style

Ana Guimarães; João Delgado; Sandra Lucas. 2021. "Advanced Manufacturing in Civil Engineering." Energies 14, no. 15: 4474.

Journal article
Published: 16 July 2021 in Energies
Reads 0
Downloads 0

This work aims to study the drying of clay ceramic materials with arbitrary shapes theoretically. Advanced phenomenological mathematical models based on lumped analysis and their exact solutions are presented to predict the heat and mass transfers in the porous material and estimate the transport coefficients. Application has been made in hollow ceramic bricks. Different simulations were carried out to evaluate the effect of drying air conditions (relative humidity and speed) under conditions of forced and natural convection. The transient results of the moisture content and temperature of the brick, and the convective heat and mass transfer coefficients are presented, discussed and compared with experimental data, obtaining a good agreement. It was found that the lower the relative humidity is and the higher the speed of the drying air is, the higher the convective heat and mass transfer coefficients are at the surface of the brick and in the holes, and the faster the moisture removal material and heating is. Based on the predicted results, the best conditions for brick drying were given. The idea is to increase the quality of the brick after the process, to reduce the waste of raw material and energy consumption in the process.

ACS Style

Elisiane Lima; João Delgado; Ana Guimarães; Wanderson Lima; Ivonete Santos; Josivanda Gomes; Rosilda Santos; Anderson Vilela; Arianne Viana; Genival Almeida; Antonio Lima; João Franco. Drying and Heating Processes in Arbitrarily Shaped Clay Materials Using Lumped Phenomenological Modeling. Energies 2021, 14, 4294 .

AMA Style

Elisiane Lima, João Delgado, Ana Guimarães, Wanderson Lima, Ivonete Santos, Josivanda Gomes, Rosilda Santos, Anderson Vilela, Arianne Viana, Genival Almeida, Antonio Lima, João Franco. Drying and Heating Processes in Arbitrarily Shaped Clay Materials Using Lumped Phenomenological Modeling. Energies. 2021; 14 (14):4294.

Chicago/Turabian Style

Elisiane Lima; João Delgado; Ana Guimarães; Wanderson Lima; Ivonete Santos; Josivanda Gomes; Rosilda Santos; Anderson Vilela; Arianne Viana; Genival Almeida; Antonio Lima; João Franco. 2021. "Drying and Heating Processes in Arbitrarily Shaped Clay Materials Using Lumped Phenomenological Modeling." Energies 14, no. 14: 4294.

Chapter
Published: 19 June 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

This chapter presents the main considerations and conclusions obtained from the results and analyses carried out in the experimental program, being valid for the materials and conditions that they were submitted.

ACS Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. Conclusions. Case Studies of Building Pathology in Cultural Heritage 2021, 69 -70.

AMA Style

António C. Azevedo, Fernando A. N. Silva, João M. P. Q. Delgado, Nicole P. S. Souza, Mahfoud Tahlaiti, Abdelhafid Khelidj. Conclusions. Case Studies of Building Pathology in Cultural Heritage. 2021; ():69-70.

Chicago/Turabian Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. 2021. "Conclusions." Case Studies of Building Pathology in Cultural Heritage , no. : 69-70.

Chapter
Published: 19 June 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

The methodological strategy of the research contemplated four distinct phases: (a) choice of a typical multi-family residential building whose pile cap foundations had presented symptoms of the occurrence of the alkali-aggregate reaction in its concrete elements; (b) choice of a foundation element more affected by the reaction: (c) extraction of concrete samples and (d) carrying out various laboratory tests to the complete characterization of the samples.

ACS Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. Methodology. Case Studies of Building Pathology in Cultural Heritage 2021, 29 -44.

AMA Style

António C. Azevedo, Fernando A. N. Silva, João M. P. Q. Delgado, Nicole P. S. Souza, Mahfoud Tahlaiti, Abdelhafid Khelidj. Methodology. Case Studies of Building Pathology in Cultural Heritage. 2021; ():29-44.

Chicago/Turabian Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. 2021. "Methodology." Case Studies of Building Pathology in Cultural Heritage , no. : 29-44.

Chapter
Published: 19 June 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

In the last decade, the occurrence of early deterioration of pile cap blocks in residential buildings and concrete bridges in the Metropolitan Region of Recife (MMR) has been reported with relative frequency. This process usually starts with the occurrence of a horizontal crack of large opening in the lateral faces of the element, located approximately 30 cm from the upper face of the block, and its installation is usually attributed to the expansions of concrete resulting from the alkali-aggregate reaction.

ACS Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. Introduction. Case Studies of Building Pathology in Cultural Heritage 2021, 1 -3.

AMA Style

António C. Azevedo, Fernando A. N. Silva, João M. P. Q. Delgado, Nicole P. S. Souza, Mahfoud Tahlaiti, Abdelhafid Khelidj. Introduction. Case Studies of Building Pathology in Cultural Heritage. 2021; ():1-3.

Chicago/Turabian Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. 2021. "Introduction." Case Studies of Building Pathology in Cultural Heritage , no. : 1-3.

Chapter
Published: 19 June 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

In this chapter the results of the analyses and tests are presented and discussed. The results of the experimental part of the dynamic modulus of elasticity, initial static modulus, compressive strength, apparent porosity and air permeability of concrete are evaluated. In the analyses performed, scanning electron microscopy, x-ray diffraction and Raman spectroscopy will be addressed.

ACS Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. Results and Discussion. Case Studies of Building Pathology in Cultural Heritage 2021, 45 -67.

AMA Style

António C. Azevedo, Fernando A. N. Silva, João M. P. Q. Delgado, Nicole P. S. Souza, Mahfoud Tahlaiti, Abdelhafid Khelidj. Results and Discussion. Case Studies of Building Pathology in Cultural Heritage. 2021; ():45-67.

Chicago/Turabian Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. 2021. "Results and Discussion." Case Studies of Building Pathology in Cultural Heritage , no. : 45-67.

Chapter
Published: 19 June 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

Concrete is a heterogeneous material, composed of a cement matrix, interfacial transition zone and aggregate. According to some researchers (Machovic, Kopecký, Nemecek, Kolár, Svítilová, Bittnar and Andertová), the typical thickness of interfacial transition zone (ITZ) is around 15–50 μm.

ACS Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. State-of the-Art. Case Studies of Building Pathology in Cultural Heritage 2021, 5 -27.

AMA Style

António C. Azevedo, Fernando A. N. Silva, João M. P. Q. Delgado, Nicole P. S. Souza, Mahfoud Tahlaiti, Abdelhafid Khelidj. State-of the-Art. Case Studies of Building Pathology in Cultural Heritage. 2021; ():5-27.

Chicago/Turabian Style

António C. Azevedo; Fernando A. N. Silva; João M. P. Q. Delgado; Nicole P. S. Souza; Mahfoud Tahlaiti; Abdelhafid Khelidj. 2021. "State-of the-Art." Case Studies of Building Pathology in Cultural Heritage , no. : 5-27.

Journal article
Published: 17 June 2021 in Sensors
Reads 0
Downloads 0

Detailed information about concrete behavior in real structures is an important issue in controlling its performance during its service life, and the use of embedded sensors to obtain desired information such as temperature, onset of the cracking process and evolution of strains, has gained the attention of the building concrete industry. Data obtained using this technology can provide valuable information for decision making about the need for corrective interventions that can ensure the integrity and safety of concrete structures for long period of time. This paper presents a review of the current state-of-the-art of embedded fiber optic sensors used to assess concrete information of a wide range of aspects, comprising: existing alternative technologies, characteristics and advantages, practical applications and future developments. Complementarily, the work presents preliminary results of the use of fiber optic sensors to automatically and continuously perform expansion readings of AAR in concrete elements that facilitate both the storage—with elimination of the usual interruptions for manual readings—and the availability of continuous results of expansion data that are not possible to obtain with usual AAR tests code reading recommendations.

ACS Style

K.K. Silva; F.A.N. Silva; T. Mahfoud; A. Khelidj; A. Brientin; A.C. Azevedo; J.M.P.Q. Delgado; A.G. de Lima. On the Use of Embedded Fiber Optic Sensors for Measuring Early-Age Strains in Concrete. Sensors 2021, 21, 4171 .

AMA Style

K.K. Silva, F.A.N. Silva, T. Mahfoud, A. Khelidj, A. Brientin, A.C. Azevedo, J.M.P.Q. Delgado, A.G. de Lima. On the Use of Embedded Fiber Optic Sensors for Measuring Early-Age Strains in Concrete. Sensors. 2021; 21 (12):4171.

Chicago/Turabian Style

K.K. Silva; F.A.N. Silva; T. Mahfoud; A. Khelidj; A. Brientin; A.C. Azevedo; J.M.P.Q. Delgado; A.G. de Lima. 2021. "On the Use of Embedded Fiber Optic Sensors for Measuring Early-Age Strains in Concrete." Sensors 21, no. 12: 4171.

Journal article
Published: 09 June 2021 in Energies
Reads 0
Downloads 0

Commonly based on the liquid diffusion theory, drying theoretical studies in porous materials has been directed to plate, cylinder, and sphere, and few works are applied to non-conventional geometries. In this sense, this work aims to study, theoretically, the drying of solids with oblate spheroidal geometry based on the thermodynamics of irreversible processes. Mathematical modeling is proposed to describe, simultaneously, the heat and mass transfer (liquid and vapor) during the drying process, considering the variability of the transport coefficients and the convective boundary conditions on the solid surface, with particular reference to convective drying of lentil grains at low temperature and moderate air relative humidity. All the governing equations were written in the oblate spheroidal coordinates system and solved numerically using the finite-volume technique and the iterative Gauss–Seidel method. Numerical results of moisture content, temperature, liquid, vapor, and heat fluxes during the drying process were obtained, analyzed, and compared with experimental data, with a suitable agreement. It was observed that the areas near the focal point of the lentil grain dry and heat up faster; consequently, these areas are more susceptible to the appearance of cracks that can compromise the quality of the product. In addition, it was found that the vapor flux was predominant during the drying process when compared to the liquid flux.

ACS Style

João Melo; João Delgado; Wilton Silva; Antonio B. Lima; Ricardo Gomez; Josivanda Gomes; Rossana Figueirêdo; Alexandre Queiroz; Ivonete Santos; Maria Machado; Wanderson Lima; João Carmo. Non-Equilibrium Thermodynamics-Based Convective Drying Model Applied to Oblate Spheroidal Porous Bodies: A Finite-Volume Analysis. Energies 2021, 14, 3405 .

AMA Style

João Melo, João Delgado, Wilton Silva, Antonio B. Lima, Ricardo Gomez, Josivanda Gomes, Rossana Figueirêdo, Alexandre Queiroz, Ivonete Santos, Maria Machado, Wanderson Lima, João Carmo. Non-Equilibrium Thermodynamics-Based Convective Drying Model Applied to Oblate Spheroidal Porous Bodies: A Finite-Volume Analysis. Energies. 2021; 14 (12):3405.

Chicago/Turabian Style

João Melo; João Delgado; Wilton Silva; Antonio B. Lima; Ricardo Gomez; Josivanda Gomes; Rossana Figueirêdo; Alexandre Queiroz; Ivonete Santos; Maria Machado; Wanderson Lima; João Carmo. 2021. "Non-Equilibrium Thermodynamics-Based Convective Drying Model Applied to Oblate Spheroidal Porous Bodies: A Finite-Volume Analysis." Energies 14, no. 12: 3405.

Journal article
Published: 27 April 2021 in Energies
Reads 0
Downloads 0

Vegetable fibers have inspired studies in academia and industry, because of their good characteristics appropriated for many technological applications. Sisal fibers (Agave sisalana variety), when extracted from the leaf, are wet and must be dried to reduce moisture content, minimizing deterioration and degradation for long time. The control of the drying process plays an important role to guarantee maximum quality of the fibers related to mechanical strength and color. In this sense, this research aims to evaluate the drying of sisal fibers in an oven with mechanical air circulation. For this purpose, a transient and 3D mathematical model has been developed to predict moisture removal and heating of a fiber porous bed, and drying experiments were carried out at different drying conditions. The advanced model considers bed porosity, fiber and bed moisture, simultaneous heat and mass transfer, and heat transport due to conduction, convection and evaporation. Simulated drying and heating curves and the hygroscopic equilibrium moisture content of the sisal fibers are presented and compared with the experimental data, and good concordance was obtained. Results of moisture content and temperature distribution within the fiber porous bed are presented and discussed in details. It was observed that the moisture removal and temperature kinetics of the sisal fibers were affected by the temperature and relative humidity of the drying air, being more accentuated at higher temperature and lower relative humidity, and the drying process occurred in a falling rate period.

ACS Style

Jacqueline Diniz; João Delgado; Anderson Vilela; Ricardo Gomez; Arianne Viana; Maria Figueiredo; Diego Diniz; Isis Rodrigues; Fagno Rolim; Ivonete Santos; João Carmo; Antonio Lima. Drying of Sisal Fiber: A Numerical Analysis by Finite-Volumes. Energies 2021, 14, 2514 .

AMA Style

Jacqueline Diniz, João Delgado, Anderson Vilela, Ricardo Gomez, Arianne Viana, Maria Figueiredo, Diego Diniz, Isis Rodrigues, Fagno Rolim, Ivonete Santos, João Carmo, Antonio Lima. Drying of Sisal Fiber: A Numerical Analysis by Finite-Volumes. Energies. 2021; 14 (9):2514.

Chicago/Turabian Style

Jacqueline Diniz; João Delgado; Anderson Vilela; Ricardo Gomez; Arianne Viana; Maria Figueiredo; Diego Diniz; Isis Rodrigues; Fagno Rolim; Ivonete Santos; João Carmo; Antonio Lima. 2021. "Drying of Sisal Fiber: A Numerical Analysis by Finite-Volumes." Energies 14, no. 9: 2514.

Chapter
Published: 25 April 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

This research aims to evaluate the reliability of computational simulation by analyzing data from simulations and field measurements (MC) of 14 case studies, in relation to internal vertical partition systems (SVVI). Comparative analysis of 75 SVVI results, SC and MC data showed that more than 50% of the simulation data showed values compatible with the in-field measurement, in the sense that they were considered potentially equal, taking into account the uncertainty of the predicted field measurement. in the evaluation methodology contained in the standard, in the order of ±2 dB. This acceptability refers to the values within the ±2 dB range of the aforementioned uncertainty. The data also showed variation between SC and MC, sometimes presenting larger SC, sometimes larger MC. The predicted hypothesis was that SC would always be higher due to the ideal conditions of the simulation, which do not occur in the field. However, where situations of MC greater than SC occurred, it was deduced that deciding on the simulation means choosing to work in favor of safety, since the minimum level of the standard is projected and better results are obtained in the field. It was also verified, through variation of the input data, that the fidelity with the technical specification of the designed systems reproduces reliable values, and the opposite, results in doubtful and discrepant data. In general, the results of the comparative analysis point to the use of computer simulation as positive, since part of the percentage that is not acceptable in this study represents doubtful measurements, and therefore, the simulation is an effective predictive tool and useful in the search for acoustic quality in residential buildings.

ACS Style

E. C. L. Rezende; A. J. Costa e Silva; A. C. Azevedo; J. M. P. Q. Delgado. Acoustic Performance Criteria in Internal Vertical Partitions: Numerical Simulations and In-Field Measurements. Case Studies of Building Pathology in Cultural Heritage 2021, 71 -165.

AMA Style

E. C. L. Rezende, A. J. Costa e Silva, A. C. Azevedo, J. M. P. Q. Delgado. Acoustic Performance Criteria in Internal Vertical Partitions: Numerical Simulations and In-Field Measurements. Case Studies of Building Pathology in Cultural Heritage. 2021; ():71-165.

Chicago/Turabian Style

E. C. L. Rezende; A. J. Costa e Silva; A. C. Azevedo; J. M. P. Q. Delgado. 2021. "Acoustic Performance Criteria in Internal Vertical Partitions: Numerical Simulations and In-Field Measurements." Case Studies of Building Pathology in Cultural Heritage , no. : 71-165.

Chapter
Published: 25 April 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

This work presents an experimental campaign with 162 specimens of cylindrical specimens of 10 × 20 cm2 and 27 prismatic specimens with 25 × 25 × 50 cm3, in order to analyse the influence of nine different concrete mixtures on compressive strength and the propagation profile of longitudinal ultrasonic waves. A neural network is best defined as a set of simple, highly interconnected processing elements that are capable of learning information presented to them and its ability to learn and process information classifies it as a form of artificial intelligence. In this work, neural networks models were used to find out the influence of several parameters used in fabrication of concrete on the material compressive strength. The results obtained showed that the simulation with neural networks associated with ultrasound tests are important tools to evaluate the compressive strength of concrete.

ACS Style

R. S. Cavalcanti; F. A. N. Silva; J. M. P. Q. Delgado; A. C. Azevedo. Compressive Strength of Concrete Estimated by Artificial Neural Networks and a Non-destructive Testing of Ultrasound. Case Studies of Building Pathology in Cultural Heritage 2021, 57 -70.

AMA Style

R. S. Cavalcanti, F. A. N. Silva, J. M. P. Q. Delgado, A. C. Azevedo. Compressive Strength of Concrete Estimated by Artificial Neural Networks and a Non-destructive Testing of Ultrasound. Case Studies of Building Pathology in Cultural Heritage. 2021; ():57-70.

Chicago/Turabian Style

R. S. Cavalcanti; F. A. N. Silva; J. M. P. Q. Delgado; A. C. Azevedo. 2021. "Compressive Strength of Concrete Estimated by Artificial Neural Networks and a Non-destructive Testing of Ultrasound." Case Studies of Building Pathology in Cultural Heritage , no. : 57-70.

Chapter
Published: 24 April 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

Acoustic forecasting models from computational simulation (SC) has been the tool used to evaluate the acoustic behavior of the building, even before the work is done, thus enabling the reduction of post-adaptation costs. This research aims to evaluate the reliability of computational simulation by analyzing data from simulations and field measurements (MC) of 14 case studies, in relation to horizontal partition systems (SVH). For the 228 SVH data, of which 116 were for SVH-RA and 102 for SVH-RI, the comparative study showed 38% acceptability between SVH-RA measurement and simulation; and 46% for SVH-RI. This acceptability refers to the values within the ±2 dB range of the aforementioned uncertainty. The data also showed variation between SC and MC, sometimes presenting larger SC, sometimes larger MC. The predicted hypothesis was that SC would always be higher due to the ideal conditions of the simulation, which do not occur in the field. However, where situations of MC greater than SC occurred, it was deduced that deciding on the simulation means choosing to work in favor of safety, since the minimum level of the standard is projected and better results are obtained in the field. It was also verified, through variation of the input data, that the fidelity with the technical specification of the designed systems reproduces reliable values, and the opposite, results in doubtful and discrepant data. In general, the results of the comparative analysis point to the use of computer simulation as positive, since part of the percentage that is not acceptable in this study represents doubtful measurements, and therefore, the simulation is an effective predictive tool and useful in the search for acoustic quality in residential buildings.

ACS Style

E. C. L. Rezende; A. J. Costa e Silva; A. C. Azevedo; J. M. P. Q. Delgado. Comparative Analysis of Numerical Simulations and Experimental Tests for Acoustic Performance in Horizontal Partitions of Buildings. Case Studies of Building Pathology in Cultural Heritage 2021, 73 -177.

AMA Style

E. C. L. Rezende, A. J. Costa e Silva, A. C. Azevedo, J. M. P. Q. Delgado. Comparative Analysis of Numerical Simulations and Experimental Tests for Acoustic Performance in Horizontal Partitions of Buildings. Case Studies of Building Pathology in Cultural Heritage. 2021; ():73-177.

Chicago/Turabian Style

E. C. L. Rezende; A. J. Costa e Silva; A. C. Azevedo; J. M. P. Q. Delgado. 2021. "Comparative Analysis of Numerical Simulations and Experimental Tests for Acoustic Performance in Horizontal Partitions of Buildings." Case Studies of Building Pathology in Cultural Heritage , no. : 73-177.

Artigos
Published: 01 April 2021 in Ambiente Construído
Reads 0
Downloads 0

Resumo O uso de pastas de gesso como revestimento de paredes internas é uma das técnicas mais comumente empregadas em obras no Brasil, geralmente efetuado em pequenas espessuras por meio de aplicação manual ou, ainda em menor espessura, por projeção mecânica. O presente trabalho objetivou avaliar experimentalmente a resistência de aderência de revestimentos executados em pasta de gesso com aplicação manual em diferentes substratos e alturas de aplicação. Como variáveis foram testados quatro tipos de blocos (blocos cerâmicos e de concreto, com função de vedação e estruturais), duas profundidades de ensaio da pasta (superficial e com cortes até o substrato) e três alturas de aplicação (até 0,6 m; entre 0,6 m e 1,2 m; e acima de 1,2 m). Os resultados apontaram a forte influência da base e da profundidade de corte na aderência, o que não foi encontrado na altura de aplicação do revestimento (ergonomia), em decorrência do natural processo de aplicação da pasta de gesso efetuado com pressão da massa sobre a parede.

ACS Style

Angelo Just Da Costa E Silva; João Manuel Do Paço Quesado Delgado; Antônio Augusto Costa de Azevedo. Avaliação experimental dos fatores de influência na aderência de revestimentos de gesso em pasta. Ambiente Construído 2021, 21, 349 -357.

AMA Style

Angelo Just Da Costa E Silva, João Manuel Do Paço Quesado Delgado, Antônio Augusto Costa de Azevedo. Avaliação experimental dos fatores de influência na aderência de revestimentos de gesso em pasta. Ambiente Construído. 2021; 21 (2):349-357.

Chicago/Turabian Style

Angelo Just Da Costa E Silva; João Manuel Do Paço Quesado Delgado; Antônio Augusto Costa de Azevedo. 2021. "Avaliação experimental dos fatores de influência na aderência de revestimentos de gesso em pasta." Ambiente Construído 21, no. 2: 349-357.

Research paper
Published: 13 March 2021 in Iranian Journal of Science and Technology, Transactions of Civil Engineering
Reads 0
Downloads 0

The paper discusses the structural behaviour of concrete struts deteriorated by internal swelling reactions due to delayed ettringite formation (DEF). To assess this behaviour, nonlinear finite elements analyses were performed using concrete damaged plasticity (CDP) model of ABAQUS, which was calibrated and validated. The effects of the internal swelling reactions were simulated numerically using a strategy of decreasing mechanical properties of concrete. MATLAB scripts were developed to automate the process of determining the CDP model parameters, especially those related to the damage in tension and compression with few input data. Decreases in the first crack and failure loads of 78% and 56% were observed which means that DEF expansions are an important issue in the load capacity of concrete structures. Besides, it was also observed a significant increase in cracks openings width, even for low expansion level, with values of 3.65 mm, and for high level of expansion with values of 4.51 mm. This is a relevant aspect for the durability of concrete structures that is severely affected by DEF expansions.

ACS Style

F. A. N. Silva; J. M. P. Q. Delgado; A. C. Azevedo; I. S. Lira. Numerical Analysis of Bottle-Shaped Isolated Struts Concrete Deteriorated by Delayed Ettringite Formation. Iranian Journal of Science and Technology, Transactions of Civil Engineering 2021, 1 -16.

AMA Style

F. A. N. Silva, J. M. P. Q. Delgado, A. C. Azevedo, I. S. Lira. Numerical Analysis of Bottle-Shaped Isolated Struts Concrete Deteriorated by Delayed Ettringite Formation. Iranian Journal of Science and Technology, Transactions of Civil Engineering. 2021; ():1-16.

Chicago/Turabian Style

F. A. N. Silva; J. M. P. Q. Delgado; A. C. Azevedo; I. S. Lira. 2021. "Numerical Analysis of Bottle-Shaped Isolated Struts Concrete Deteriorated by Delayed Ettringite Formation." Iranian Journal of Science and Technology, Transactions of Civil Engineering , no. : 1-16.

Chapter
Published: 11 March 2021 in Case Studies of Building Pathology in Cultural Heritage
Reads 0
Downloads 0

The environmental impact of cement production was increased significantly in the last years. It is estimated that for each ton of cement produced, approximately one ton of carbon dioxide is emitted, divided into: decarbonation (50%), combustion in the clinker furnace (40%), transport of raw materials (5%) and electricity (5%). From a world perspective, green strategies have been advanced in order to reduce the environmental impact of the cement production. In this sense, the sugar cane bagasse ash is a by-product resulted from boilers of sugar and alcohol factories. This material, composed mainly of silica, can be used as a mineral admixture in mortar and concrete, with great economic and environmental advantages. This work intent to collaborate for the partial substitution of Portland cement by sugar cane bagasse (SCB), in order to reduce the consume of clinker by volume of concrete, which is the responsible for the high emission of CO2 to the atmosphere. For this, an experimental campaign was carried out with cementitious pastes to evaluate the changes in their properties, namely the durability, due to the use of SCB ash. Finally, it could be concluded that concrete structures with sugar cane bagasse ash presented an interesting behavior and, in terms of durability, the samples containing 15% of the ash of sugarcane bagasse showed good results, being important to highlight the need and interest of doing further research on the topic.

ACS Style

J. M. P. Q. Delgado; R. Berenguer; N. Lima; A. C. Valdés; M. H. F. Medeiros; A. C. Azevedo. Influence of the Addition of Sugar Cane Bagasse Ash on Durability of Concrete Structures. Case Studies of Building Pathology in Cultural Heritage 2021, 115 -171.

AMA Style

J. M. P. Q. Delgado, R. Berenguer, N. Lima, A. C. Valdés, M. H. F. Medeiros, A. C. Azevedo. Influence of the Addition of Sugar Cane Bagasse Ash on Durability of Concrete Structures. Case Studies of Building Pathology in Cultural Heritage. 2021; ():115-171.

Chicago/Turabian Style

J. M. P. Q. Delgado; R. Berenguer; N. Lima; A. C. Valdés; M. H. F. Medeiros; A. C. Azevedo. 2021. "Influence of the Addition of Sugar Cane Bagasse Ash on Durability of Concrete Structures." Case Studies of Building Pathology in Cultural Heritage , no. : 115-171.

Journal article
Published: 09 March 2021 in Buildings
Reads 0
Downloads 0

Early deterioration of reinforced concrete foundations has been often reported in recent years. This process is usually characterized by an extensive mapping cracking process on concrete surfaces that results from several types of Internal Swelling Reaction (ISR). In this paper, a real case study of a tall reinforced concrete building with a severe deterioration process installed in its deep foundations is discussed. Laboratory tests were performed in concrete drilled cores extracted from a deep pile cap block 19 years after the beginning of construction. Tests to assess the compressive strength, the static and the dynamic modulus of elasticity, the gas permeability, and electron microscopy scanning to find out the primary mechanism responsible for the deterioration observed during in situ inspections. Chemical alterations of materials were observed in concrete cores, mainly due to Delayed Ettringite Formation (DEF), which significantly affected the integrity and durability of the structure. Dynamic modulus of elasticity showed to be a better indicator of damage induced by ISR in concrete than compressive strength. Procedures to strengthen the deteriorated elements using prestressing proved to be an efficient strategy to recover the structural integrity of pile caps deteriorated due to expansions due to ISR.

ACS Style

Fernando Silva; João Delgado; António Azevedo; Tahlaiti Mahfoud; Abdelhafid Khelidj; Nicole Nascimento; António Lima. Diagnosis and Assessment of Deep Pile Cap Foundation of a Tall Building Affected by Internal Expansion Reactions. Buildings 2021, 11, 104 .

AMA Style

Fernando Silva, João Delgado, António Azevedo, Tahlaiti Mahfoud, Abdelhafid Khelidj, Nicole Nascimento, António Lima. Diagnosis and Assessment of Deep Pile Cap Foundation of a Tall Building Affected by Internal Expansion Reactions. Buildings. 2021; 11 (3):104.

Chicago/Turabian Style

Fernando Silva; João Delgado; António Azevedo; Tahlaiti Mahfoud; Abdelhafid Khelidj; Nicole Nascimento; António Lima. 2021. "Diagnosis and Assessment of Deep Pile Cap Foundation of a Tall Building Affected by Internal Expansion Reactions." Buildings 11, no. 3: 104.

Journal article
Published: 25 February 2021 in Buildings
Reads 0
Downloads 0

This work aims to study the influence of using construction and demolition waste in the replacement of coarse and fine aggregate to produce recycled aggregate concrete (RAC). A moderate compressive strength concrete made with usual fine and coarse aggregate was used as a benchmark material. Compressive and split tensile tests were performed using 120 cylindrical concrete specimens with 150 mm diameter and 300 mm length. Four-point flexural tests in reinforced beams made with conventional concrete and RAC were performed. The results obtained showed that the use of recycled fine aggregates, in both percentages of substitution investigated—50% and 100%—did not generate any deleterious influence on the values of compressive strength and split tensile strength of the RACs produced. Tin fact, the mechanical strengths of RACs produced with recycled fine aggregate were equal or higher than those from the reference concrete. The same behavior was not observed, however, when the recycled coarse aggregate was used. For this case, decreases in concrete mechanical strengths were observed, especially in compressive strength, with values around 35% lower when compared to the reference concrete. Tensile mechanical tests results confirmed the excellent behavior of all RACs made with replacement of usual fine aggregates by recycled. Bending tests performed in reinforced RAC beams had as objective to evaluate the deformation profile of the beams. The obtained results showed that RAC beams with full replacement of usual fine aggregate by the recycled aggregates have presented little changes in the global behavior, an aspect that encourages its use.

ACS Style

Fernando Silva; João Delgado; António Azevedo; António Lima; Castorina Vieira. Preliminary Analysis of the Use of Construction Waste to Replace Conventional Aggregates in Concrete. Buildings 2021, 11, 81 .

AMA Style

Fernando Silva, João Delgado, António Azevedo, António Lima, Castorina Vieira. Preliminary Analysis of the Use of Construction Waste to Replace Conventional Aggregates in Concrete. Buildings. 2021; 11 (3):81.

Chicago/Turabian Style

Fernando Silva; João Delgado; António Azevedo; António Lima; Castorina Vieira. 2021. "Preliminary Analysis of the Use of Construction Waste to Replace Conventional Aggregates in Concrete." Buildings 11, no. 3: 81.

Journal article
Published: 08 February 2021 in Membranes
Reads 0
Downloads 0

Wastewater from the oil industry can be considered a dangerous contaminant for the environment and needs to be treated before disposal or re-use. Currently, membrane separation is one of the most used technologies for the treatment of produced water. Therefore, the present work aims to study the process of separating oily water in a module equipped with a ceramic membrane, based on the Eulerian–Eulerian approach and the Shear-Stress Transport (SST k-ω) turbulence model, using the Ansys Fluent® 15.0. The hydrodynamic behavior of the water/oil mixture in the filtration module was evaluated under different conditions of the mass flow rate of the fluid mixture and oil concentration at the entrance, the diameter of the oil particles, and membrane permeability and porosity. It was found that an increase in the feed mass flow rate from 0.5 to 1.5 kg/s significantly influenced transmembrane pressure, that varied from 33.00 to 221.32 kPa. Besides, it was observed that the particle diameter and porosity of the membranes did not influence the performance of the filtration module; it was also verified that increasing the permeability of the membranes, from 3 × 10−15 to 3 × 10−13 m2, caused transmembrane pressure reduction of 22.77%. The greater the average oil concentration at the permeate (from 0.021 to 0.037 kg/m3) and concentrate (from 1.00 to 1.154 kg/m3) outlets, the higher the average flow rate of oil at the permeate outlets. These results showed that the filter separator has good potential for water/oil separation.

ACS Style

Guilherme Oliveira Neto; Nívea Oliveira; João Delgado; Lucas Nascimento; Hortência Magalhães; Paloma Oliveira; Ricardo Gomez; Severino Farias Neto; Antonio Lima. Hydrodynamic and Performance Evaluation of a Porous Ceramic Membrane Module Used on the Water–Oil Separation Process: An Investigation by CFD. Membranes 2021, 11, 121 .

AMA Style

Guilherme Oliveira Neto, Nívea Oliveira, João Delgado, Lucas Nascimento, Hortência Magalhães, Paloma Oliveira, Ricardo Gomez, Severino Farias Neto, Antonio Lima. Hydrodynamic and Performance Evaluation of a Porous Ceramic Membrane Module Used on the Water–Oil Separation Process: An Investigation by CFD. Membranes. 2021; 11 (2):121.

Chicago/Turabian Style

Guilherme Oliveira Neto; Nívea Oliveira; João Delgado; Lucas Nascimento; Hortência Magalhães; Paloma Oliveira; Ricardo Gomez; Severino Farias Neto; Antonio Lima. 2021. "Hydrodynamic and Performance Evaluation of a Porous Ceramic Membrane Module Used on the Water–Oil Separation Process: An Investigation by CFD." Membranes 11, no. 2: 121.