Engenharia Civil

URI Permanente para esta coleçãohttps://tede2.unicap.br/handle/tede/5

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Chemical and creep models applied for concrete Affected by alkali-aggregate reaction.
(Universidade Católica de Pernambuco, 2021-07-13) Roma, Rodrigo Figueiredo; Tahlaiti, Mahfoud; Bourbatache, Khaled; Silva, Fernando Arthur Nogueira; Oliveira, Joaquim Teodoro Romão de; Khelidj, Adelhafid
Structures de béton que souffrent à cause de la réaction alkali-granulat sont aussi affectées per autres mécanismes de détérioration comme le fluage et le rétrécissement. Au Brésil et dans autres pays au monde, cas nombreux des fondations des constructions et béton DAMS ont été investigués à cause du dommage associé à la réaction alkali- granulat. Modèles macroscopiques de la réaction alkali-granulat doivent considérer l'influence des paramètres naturels principaux, comme température, dégrée de saturation e la vitesse d'évolution de la réaction chimique. Pour être relevant aux applications des structures, modèles de fluage béton doivent considérer plusieurs phénomènes importants, comme la non-linéarité, multi-axialité, e des effets thermaux et de séchage. Pour prévenir ces pathologies, réhabilitation des plans ou créer nouvelles procédures de design, la simulation numérique pour la méthode des éléments finis est reconnue comme un outil très utile. Le but de cette recherce est d'implémenter un modèle chimique pour simuler l'avancement de la réaction et un modèle pour simuler les phénomènes de fluage et le rétrécissement sur COMSOL Multiphysics®, comme un moyen de réévaluer des structures de béton qui souffrent de ces mécanismes. Le modèle pour représenter la réaction alkali-granulat a été développé pour Morenon (2017) et les modèles de fluage et de rétrécissement ont été développés pour Sellier et al. (2016), utilisés aujourd'hui pour autres softwares commerciales comme CAST3M et Code_Aster. Les modèles ont été implémentés en COMSOL séparément afin d'évaluer les réponses, en comparaison avec les résultats théoriques et les repères expérimentaux proposées pour les développeurs de ces modèles. Le modèle chimique pour reproduire la réaction alkali-granulat a été comparé aux résultats théoriques montrés par le développeur du modèle (Morenon, 2017) et le modèle de fluage a été comparé aux données expérimentales concernant les déformations de fluage dans différentes directions d'un échantillon sous diverses charges et différentes températures. Les résultats de la simulation ont été en assez bon accord avec les résultats tirés de la littérature, avec un erreur limite de 10%, que montre que l'implémentation en COMSOL a été un succès. Le modèle de rétrécissement n'a pas montré des bons résultats, et quelques instabilités numériques des modèles ont été trouvées quand la couplage des modèles est fini, et pour reproduire complètement une structure de béton affectée par ces phénomènes de détérioration, une comparaison chimio-mécanique-dommage dans un cadre rhéologique doit être mis en œuvre, ce qui sera l'objectif des prochains projets de recherche.
Effects of internal expansion reactions on the mechanical properties of concrete.
(Universidade Católica de Pernambuco, 2024-02-06) Lucena, Maria Eduarda Maia Ferreira Gomes; Silva, Fernando Arthur Nogueira; Azevedo, Antônio Augusto Costa de; Monteiro, Eliana Cristina Barreto
Among the various deleterious actions that can attack concrete elements is the alkali-aggregate reaction (AAR), which mainly affects the structures of dams, bridges and foundations, the most recurrent of which is the alkali-silica reaction (ASR). Due to the early deterioration of concrete in residential buildings and bridges in the Metropolitan Region of Recife, scientific studies have been carried out over the last decade to find out how this process works, with the aim of developing measures that can provide an acceptable level of performance and durability, in accordance with the regulations in use. One of the main challenges in predicting this phenomenon is understanding how the mechanical properties of concrete are affected, which is the subject of this research. In this master's research, samples made in the laboratory were tested to evaluate the ASR and its effect on the mechanical properties of the concrete samples. The tests carried out were compressive strength, static modulus of elasticity of the concrete and tensile strength, using different cements: CPIV and CPV. Visually, it was possible to identify some cracks on the surfaces of the samples and traces of silica gel. The values of the concrete's mechanical properties showed different results: the concrete's compressive strength was little reduced by the reaction. On the other hand, the static modulus of elasticity was significantly reduced by 35% and 38% for each cement respectively. The tensile strength was reduced by 9% and 30%, but these results must be analyzed carefully, given the conditions in which they were tested. Therefore, the method used to create artificial ASR proved to be effective and has the potential to be used in further ASR studies. The modulus of elasticity also proved to be the most suitable tool for detecting the presence of ASR.
Avaliação da influência do teor de cal nas propriedades reológicas e mecânicas das argamassas mistas de cimento para revestimento.
(Universidade Católica de Pernambuco, 2023-12-19) Amorim, Elanny Carolynne de Almeida; Costa e Silva, Ângelo Just da; Monteiro, Eliana Cristina Barreto; Mota, João Manoel de Freitas
The rheological behavior of a mortar is represented by relations between the deformation of a fluid and the forces to which it is subjected, so that rheology is the science that studies the flow and deformation of matter by evaluating the relations between applied shear stress and its deformation over a given period of time. The mortars used for coatings comply with rheological concepts when analyzed in their fresh state, when they are manipulated and applied to their different uses, promoting good results in the hardened state. As it is a mixture of binders and inert materials, respectively Portland cement, hydrated lime and fine aggregates, it is natural that the proportions and quantities present of each of these components interfere with the behavior of the mortars, whether in their fresh (rheological) or hardened. The objective of this work is to present how variation in the content and type of hydrated lime influences the rheological properties of coating mortars, and its consequences also on the mechanical properties after hardening, based on tests carried out in the laboratory simulating field conditions. As the main conclusions of this study, the proposed methods proved to be relevant characterizations, with small variations in results. It was also observed that the increase in lime content has a positive effect on the rheological parameter, increasing its flow capacity in a flowing situation, as well as a negative effect on the properties of the mortar in the hardened state.
Análise geomecânica de encostas em municípios do agreste pernambucano.
(Universidade Católica de Pernambuco, 2023-08-30) Silva, Jairo Lopes da; Oliveira, Joaquim Teodoro Romão de; Oliveira, Pedro Eugenio Silva de; Zarzar Júnior, Fuad Carlos
The occurrence of mass movements, which took place in large numbers in 2022, on the banks of Highway PE-177, the road linking the municipalities of Quipapá and Garanhuns, in the arid zone of Pernambuco, sparked our interest in analyzing the geomechanical behavior of these slopes belonging to the Borborema Plateau, with the aim of investigating the factors that caused these events. The investigation included analyzing the factors according to the literature, as well as collecting samples for laboratory tests. The investigation led us to conclude that the rainfall recorded in the region in 2022 was more than double the historical average, a factor intrinsically linked to the events. Using the Unified Classification System (USCC), we found that the two samples are classified as clayey (CH), with high compressibility, as they both have LL >50. When they were subjected to the direct shear test, the soil decreased as the humidity increased (saturated condition), while the friction angle did not change much. The steepness of the slopes contributes directly to the occurrence of landslides, because the steeper the slope, the greater the increase in density, which reduces cohesion, creating overload and leading to rupture. The vegetation on the slopes also contributes to the landslide phenomenon.
Análise da resistência de aderência à tração de revestimento cerâmico aplicado em parede de concreto moldada in loco com diferentes tipos de tratamento de base: escova e lavagem com água e desbaste mecânico.
(Universidade Católica de Pernambuco, 2023-07-27) Novaes, Delza Coelho Sobral de Aquino; Costa e Silva, Ângelo Just da; Monteiro, Eliana Cristina Barreto; Mota, João Manoel de Freitas
As Brazil occupies a prominent place in the world scenario of consumption and production of ceramic tiles, it is important to evaluate the quality and performance of the commercial mortars used in the process. The objective of this work was to verify which mortar presented the highest tensile adhesion resistance of the ceramic coating applied to a concrete wall cast in situ with a specific type of adhesive mortar manufacturer using the three types AC-I, AC-II and AC-III . This work is a case study and was carried out on a construction site using an unwashed cast-in-place concrete wall, washed with water and using mechanical grinding. This wall was divided into three parts and 72 ceramics were placed in each part, totaling 216 units of 10cm x 10cm ceramics placed on this wall and each part was used with three types of mortar. This study will be important when choosing the best mortar when laying ceramics on this type of substrate, as the tensile strength values can be determined through the pull-out test (NBR 13754:2016). It was found that the three mortars did not meet the standard regarding untreated walls, with treatment using a steel brush and washing with water. The AC-II and AC-III types of mortar used in the experiment met the NBR 13749 (2013) standard for concrete walls with mechanical grinding treatment. All this observation will be important during the executive process, as it will help in the best choice of the type of treatment applied to the substrate before applying the ceramic coating.
Análise das vibrações geradas pela cravação de estacas em obras da cidade do Recife.
(Universidade Católica de Pernambuco, 2023-04-12) Andrada, Raíssa Barros Vieira; Gusmão, Alexandre Duarte; Oliveira, Joaquim Teodoro Romão de; Silva, Angelo Just Costa e; Albuquerque, Paulo José Rocha de
The choice of the type of foundation when intending to build a real estate development is extremely important since its execution and nailing can interfere with neighboring buildings both in the disturbance of daily life with the generation of vibrations and sounds and in the issue of structural impacts on homes. neighbors. These factors lead to a series of legal disputes between the construction company and neighboring residents. The present work aims to study and analyze, through tests carried out in situ using the geophone device, the acceleration of particles in a medium in the directions: longitudinal, sagittal, and transversal, which are expressed in Peak Particle Velocity (PPV) and frequency. These measurements were carried out in several works, called case studies, located in the city of Recife and Metropolitan Region (Ipojuca), Pernambuco. Each case study contained a type of pile and execution to be measured, named: precast concrete pile, metal pile, root pile, mortar pile and continuous flight auger. With the aid of the geophone, measurements were carried out at a certain safe distance from the execution equipment. The results and values of peak particle velocity and frequency were analyzed and compared with current international standards and other existing case studies. It was found that precast concrete piles and the method using a hydraulic hammer presented the highest values of peak particle velocity. Regarding frequency, root-type cuttings presented the highest values. It is worth noting that even though they did not obtain the highest particle peak value, the metallic type piles also obtained significant values in terms of their peak particle velocity.
Contribuição ao entendimento do fenômeno do transporte de umidade na alvenaria de blocos de cerâmicas assentada com argamassa cimentícia.
(Universidade Católica de Pernambuco, 2022-09-30) Freitas, Letícia Mendes de; Azevedo, Antônio; Nogueira, Fernando Artur; Silva, Angelo Just da Costa e; Delgado, João Manuel do Paço Quesado
In Brazil, buildings use ceramic bricks and Portland cement mortar as constituent materials for the walls of buildings, which act as coatings and delimiting elements for internal areas. These materials are porous and highly susceptible to degradation due to the presence of moisture. Water penetrates structures through pores and compromises the useful life of buildings if not identified and treated early. The region between one layer and another of a wall is called the interface, and due to the presence of this region, the moisture transport in multilayer elements differs from those found in monolithic elements. The change in moisture transport behavior is proportional to the change in the nature of the contact and the water properties of the interface, and is called the Interface Resistance. The research discusses the behavior of moisture transport in specimens composed of ceramic brick and cementitious mortar, with different contact configurations, mortar traces and base dimensions. We sought to understand how these factors influence the cumulative moisture flow, the moisture content of porous materials and the water resistance of the interface. An extensive experimental program was developed with tests on 180 specimens. Three mixes of mortar, in mass, using CP V cement, hydrated lime, washed sand and distilled water were prepared: 1:2:9, 1:1:6 and 1:0.5:4. The specimens had a square base with sides measuring 5 cm, 7 cm and 10 cm. The research investigated hydraulic and perfect contact. For each contact configuration, 90 specimens were made, 30 for each mortar mix. Different performances were observed for specimens of different traits, where some absorbed less water than others. When comparing the different areas of the bases of the specimens for each mix, in all cases the absorption (moisture content) of water increases when the area is increased. The calculation of the water resistance was carried out by two different methodologies, with an important difference between them in the final result, even though they were in the same order of magnitude.
Aplicação e importância do projeto eSocial: riscos ambientais em marmorarias.
(Universidade Católica de Pernambuco, 2023-06-12) Santos, Félix Gustavo de Andrade; Albuquerque, Siderley Fernandes; Oliveira, Joaquim Teodoro Romão de; Zarzar Júnior, Faud Carlos; Pereira, Daniel Duarte
The regulatory norms establish requirements and guidelines with the objective of ensuring the prevention of the safety and health of workers. Despite the existence of a robust regulatory framework, many employers fail to comply with the guidelines, acting only upon inspection and notification by the Ministry of Labor. The eSocial program was implemented by the federal government with the aim of creating digital bookkeeping platforms for tax, social secunty and labor obligations. Based on the existing misinformation about the program, the objective was to demonstrate the application and importance of the eSocial program in the production chain of civil construction, with emphasis on the environmental risks existing in marble factories. Five marble factories in the Sertão Paraibano were selected. Noise, breathable dust and silica were evaluated in the cutting sector between the years 2018 and 2023. For noise, measurements were performed with the aid of audiodosimeters. In each marble factory, three workers were selected and the equipment was installed in them, close to the auditory zone, remaining there for at least 75% of the daily workday. The average sound level (Lagv, in dB), the percentage of permitted daily exposure to noise (DOSE, 1%) and the normalized exposure level (NEN, in dB) were calculated. Breathable dust and silica were obtained with the aid of a sampling pump coupled with a cassette and a cyclone, installed on the worker's waist and remaining during the daily working day. The volume of air (liters), respirable dust (mg/m²), crystalline silica (%) and tolerance limit (LT, in mg/m³) were obtained. In all companies, Lagy and NEN were higher than the allowed LT of 85 dB. The DOSE also exceeded the maximum allowed percentage of 100%, with values up to five times the allowed dose. In companies 1 and 2, the concentration of respirable dust was approximately twice the calculated LT, however, no silica was detected. In companies 3 and 4, it was observed that the respirable dust was slightly above the LT and the percentage of silica was detected, 60.03 and 9. 14%, respectively, indicating that workers are exposed to the chemical agent. In company 5, silica was not detected and the respirable dust concentration was 0.88 mg/m3, well below the LT of 3 mg/m². The results point to a situation of insecurity for workers, with senous health risks. It is urgently recommended to adopt collective, administrative measures and the use of personal protective equipment, which eliminate or mitigate the existing risks, Greater rigor is needed in controlling these risks, as well as greater oversight by the competent bodies. With regard to the social security repercussions of the eSocial program, the risks found guarantee special retirement for workers in the analyzed companies. Employers must proceed with the payment of a social security contribution to the federal government, at rates between 6 and 12%, which are levied on workers' remuneration.
Produção de bloco de gesso e cinzas de carvão mineral aditivados com sal orgânico à base de óleos vegetais.
(Universidade Católica de Pernambuco, 2023-07-07) Amaral, Rafael Filgueira; Santos, Valdemir Alexandre dos; Oliveira, Joaquim Teodoro Romão de; Pappalardo, Juliano Rodrigues
One of humanity's great challenges is to rationalize the use of environmental resources, so as not to compromise the existence of future generations – elaboration of sustainable processes and products. Gypsum has properties such as the availability of cheap raw materials, volumetric stability, acoustic and thermal insulation, fire resistance, low toxicity, however, it has low resistance to water absorption. The objective of this research was to rationalize a production process for the separation of gypsum and mineral coal ash, added with an organic salt based on essential oils, commercially known as DS-328 (Synthetic Termite Sludge) and Sulfate of Aluminum. This additive was used with a view to using partition blocks, based on plaster, for wet areas in buildings. An essential reason for reducing the amount of gypsum was to ensure that the semi-hydrate content in the gypsum was equal to or greater than 85.0%. The properties of the specimens made were evaluated with the aid of an experimental design of the type Rotational Composite Design (DCCR), through the application of the STATISTICA software from StatSoft, Version 12. The proposed composite had its specimens from the hardening of the paste with a water/plaster ratio of 60% m/m (< water/plaster content than the conventional one). The composite formulation showed dependence with the type of response variable. Thus, on average, values of: setting time (TP) = 10.15 min; Resistance to pain (RC) = 13.29 MPa e; Water absorption (AA) = 11.65%. The addition of DS-328, chemically aided with commercial aluminum sulfate (chemical stabilization function), increased the strength resistance and improved the hydrophobic character of the composite in relation to the properties of pure gypsum. The results obtained with the gypsum-CCM mixture added with DS-328 led to a reduction in gypsum consumption through the use of mineral coal ash (environmental liability), giving rise to a new material for separation blocks for ecological areas.
Comparativo de custos entre uso de tijolos de solo-cimento e blocos cerâmicos em construções populares na cidade do Recife–PE.
(Universidade Católica de Pernambuco, 2023-04-18) Carvalho, Antonio Paulo de Menezes; Oliveira, Romilde Almeida de; Oliveira, Joaquim Teodoro Romão de; Zarzar Junior, Faud Carlos; Mota, João Manoel de Freitas
Looking for new building materials, there has been increasing attention to the environmental impacts generated and ways to reduce them. In this search, the use of stabilized soil, one of the first construction materials used by humans but fell out of use due to the evolution of other technologies, has been reconsidered. This study examines the financial feasibility of using modular soil-cement bricks, comparing this construction technique with a traditionally used technique using ceramic masonry, pointing out the advantages and disadvantages of each. For this comparison, budgets were prepared for a low-cost house using each construction methodology, aiming to establish a parallel between the construction costs and the structural safety provided by each. The results obtained show that there is financial viability for the production and use of soil-cement bricks in the current construction industry, since the construction costs using this method were very close to those using the traditional method with ceramic masonry, even with the low availability and high cost of soilcement masonry.
Utilização eficiente da escória aciaria como adição nos agregados na fabricação de pavers vibro prensado.
(Universidade Católica de Pernambuco, 2022-06-08) Lima, Leandro Mendonça de; Monteiro, Eliana Cristina Barreto; Silva, Angelo Just da Costa e; Martins, Eliziane Jubanski
Currently, the steel manufacturing process follows clearly defined stages. In this process, production waste is generated in some stages, previously considered by-products and discarded without any treatment. With the technological and scientific development of emerging industries, it can be seen that some of these tailings can be reused in the process, or they can have other destinations, being considered by-products of steel manufacturing. these by-products is steel slag, which represents a large amount of slag produced per ton of steel. Faced with such quantity and legal and environmental requirements, it is starting to analyze the possible destinations of these by-products instead of disposal. From this study, it appears that steel slag can be used as a substitute for other inputs in the production chain. Thus, the research aimed to evaluate the efficient use of steel slag as an addition to fine and coarse aggregates in the manufacture of pressed vibrating pavers. Analyzing the compressive strength results, all the mixes reached above 35 MPa at the end of 28 days, only the mixes with slag addition had greater strength gains at the end of 91 days, which is a positive point to be noted. All pavers with and without slag had low water absorption, with pavers with 35% slag having the highest porosity. As for the wear of pavers by abrasion, there was low variation in all traces. The pavers that presented the best quality and strength performance were referring to the traces with 20% slag.
Numerical simulation of moisture transport along ceramic brick interfaces.
(Universidade Católica de Pernambuco, 2022-05-26) Araújo, Camila Mota de; Azevedo, Antônio Augusto Costa de; Silva, Fernando Artur Nogueira; Oliveira, Joaquim Teodoro Romão de; Silva, Ângelo Just da Costa e; Delgado, João M. P. Q.
Moisture transport in brick masonry is an important phenomenon in various deterioration mechanisms. However, it is a very complex process and is influenced by many physical phenomena. The investigation of moisture transfer through a building wall, which in general consists of multiple layers, presupposes knowledge about the continuity between the layers. In this study, two types of contact configurations were analyzed, as follows: Perfect Hydraulic Contact and Air Space Interface. Therefore, to understand moisture transport in brick masonry, moisture transport through the materials' interface was analyzed. This was done for cement mortar and brick samples, lime mortar and brick samples, and samples with air space between brick layers, as well as for samples with different interface location heights and different air space thicknesses. Mainly, the present work aims to simulate the hygrothermal behavior through brick-mortar and brick-brick interfaces in samples with perfect hydraulic contact and with air space between brick layers to compare the results with laboratory analyses. The numerical simulations of brick-mortar and brick-brick samples were performed with WUFI-2D hygrothermal simulation software. WUFI-2D is a computer program, based on the hygrothermal calculation model, which has at its base a coupled transport equation system and numerical solution technique, developed by Künzel (1995). The data used to run the simulations were extracted from water absorption tests on laboratory samples; the corresponding moisture content profiles were measured using gamma ray spectrometers. Although the mechanisms of moisture transport in a single building material have been and continue to be extensively studied, the hydraulic characteristics of the interface at different types of contacts between materials are still poorly understood and, for this reason, the simplified assumption of perfect hydraulic contact, is widely used in hygrothermal models. In general terms, the assumption of perfect hydraulic contact implies that the interface will have no effect on moisture transport. In comparison, the assumption of imperfect hydraulic contact implies that the interface between building materials will resist moisture transport. However, comparisons between the experimental and numerical results showed a large difference in the moisture transport behavior for samples with perfect hydraulic contact and imperfect hydraulic contact due to the influence caused by the interface.
Impacto do acompanhamento de obras públicas utilizando as técnicas de gerenciamento de obras privadas.
(Universidade Católica de Pernambuco, 2022-08-30) Bezerra, Edvaldo Gonçalves; Monteiro, Eliana Cristina Barreto; Silva, Ângelo Just da Costa e; Mota, João Manoel de Freitas
The study seeks to nurture the municipal public services of several successful techniques used in the management of private works, to improve the performance in the management and control of these services, trying to bring the efficiency of the public service closer to the performance of the management of private services. With this objective, a quantitative research of a qualitative nature will be used, which will be proposed to professionals directly involved in the management and inspection services of municipal public bodies in seven municipalities in the metropolitan region of Recife, through questions that envision opportunities for the insertion of techniques and private management concepts, applied to municipal public works. The objective of this research is that the opinion of the universe of professionals involved in the inspections of public services is known, regarding the contribution of improvement in performance, efficiency and professional transparency of the services provided to taxpayers. Knowing in advance, that this is a small portion of the union, but that it has the possibility of offering parameters to follow and direct future broader studies. However, at the conclusion of possession of the results achieved with the field research, where the wishes of the professionals involved in the inspection will be verified and if there is a relevant contribution to society of the use of private management techniques in public works, bringing and contributing with benefits to society .
Balanço de Co2 (dióxido de carbono), no Bloco G da Universidade Católica de Pernambuco.
(Universidade Católica de Pernambuco, 2022-08-15) Maciel, Pedro Adolfo Rodrigues; Oliveira, Romilde Almeida de; Oliveira, Joaquim Teodoro Romão de; Mota, João Manoel Freitas
This scientific research aims show the balance CO2 in the block “G” of UNICAP, analyzing specimens extracted from the main structural elements (beams, pillars and slabs); Describe the history of the structure; constructive method; design parameters, comparing the regulatory requirements of the time with the current ones and geographic location. The building in question is “Block G” of the Catholic University of Pernambuco (UNICAP), Built in 1980, located in the city of Recife, at a distance of 500m from the Capibaribe River and 2.02 km from the Atlantic Ocean. Emphasizing the identification of the presence of aggressive agents, mainly carbon dioxide with phenolphthalein spray, but also chloride ions, with silver nitrate (AgNO3) spray. Specimens extracted from the pillars, slabs and beams of the longest facades of the building. Totaling 90 specimens analyzed, distributed among nine floors. A microscopic analysis of the concrete was also carried out, with the analysis in the scanning electron microscope (MEV), with seven specimens, in order to understand its structure, correlating defects and properties and identifying the properties of the materials used. To verify the concrete compressive strength of the structure and compare it with the design parameters, a compressive strength test was performed on seven specimens in a specialized laboratory. Through the results obtained, we can verify which areas of the building are most affected and analyze the results of emission CO2 in environment as relate the CO2 captured by the structure. The identification of these agents demonstrates how the structure is suffering with a high probability of corrosion and degradation? what kinds of structural maintenance and recovery and which agents in each position on bulid, in view of their geographical position in relation to the sea and effect of the region's winds, in addition to analyzing the design parameters used at the time compared to the current ones and identifying their evolution and efficiency.
Análise e levantamento das manifestações patológicas através de mapa de danos, em prédios históricos do estado de Pernambuco, devido a falta de manutenção e recuperação.
(Universidade Católica de Pernambuco, 2022-08-03) Borba, Lucas Feliciano Ferreira; Monteiro, Eliana Cristina Barreto; Silva, Ângelo Just da Costa e; Mota, João Manoel de Freitas
Today, there is a focus on the quality and performance of buildings. Durability and longevity of construction materials are concepts that were not evaluated in buildings before and today are fundamental to the decisions of design and execution of buildings. The city of Recife has a great variety of historical monuments that present many pathological manifestations that degrade the structure, reduce its useful life and put at risk the stability of our precious patrimony. In view of this, there are concerns about the correction of these pathological manifestations and the preservation of this heritage. Studying the pathological manifestations of historic buildings becomes fundamental, because this is the way to understand the mechanisms that degenerate them. The lack of maintenance favors this problem, as it can lead to the development and dissemination of anomalies, increasingly reducing the service life of the structure. The study was developed with the purpose of stimulating the valorization of Pernambuco's heritage riches. For this, 03 buildings of the city were chosen, namely, the São José Church of the extinct São José retreat house, the Museum of Archeology and Natural Sciences, and the Nossa Senhora de Fátima Church. These were selected according to the following criteria: listing by the Institute for National Historic and Artistic Heritage - IPHAN; social importance; accessibility; and availability of data. This study aims to evaluate the conservation status of the facades of buildings located in the city of Recife and Olinda in order to contribute to the restoration and/or conservation of the selected buildings. The methodology used in the research began with a literature review, followed by the selection of the buildings with the application of a check-list, which allows the elaboration of a data identification sheet, photographic record, and verification of the lack of maintenance, essential tools for the composition of the Damage Map of the studied facades. With the data collected, the information was compiled and the damage maps of the buildings studied were composed, and the most recurrent manifestations on the facades of the buildings studied were dirtiness/black crust and paint detachment. The study of the pathology of the buildings and the use of Damage Maps are fundamental tools for the treatment and preservation of historic buildings. The material produced facilitates the execution of future restorations, besides promoting and valuing the historic heritage of Recife.
Estudo de viabilidade técnica e econômica de fundação em estacas para um projeto robusto ao colapso progressivo.
(Universidade Católica de Pernambuco, 2022-08-19) Santos, José Cláudio Barbosa dos; Oliveira, Joaquim Teodoro Romão de; Oliveira, Romilde Almeida de; Zarzar Júnior, Fuad Carlos; Mota, João Manoel Freitas
With the advance of the computational simulation capacity and the development of alternatives to solve structural problems, it became possible the modeling of structures with behavior analogous to a real structure. Based on this premise, this paper aims to expose the feasibility study of the modeling of a building with stakes foundation, assuming that: in case any of the stakes rupture, adopting a robust design of the structure, designed with the objective of compensating the local failure, the building will not have its stability compromised. For this, it was used a program based on the Finite Element Method - FEM, being possible to observe, in case of an accident, the behavior of the efforts, moments and displacements of the conventional structure, interpreting the results of its contribution to the progressive collapse and thus dimensioning the robust structure capable of preventing this phenomenon. The estimated value of safety, considering only the execution costs of the conventional structure, compared to the robust structure, is 5.79%, but when the values covering all the steps for the construction of the conventional building and the robust building are verified, this percentage represents only 1.62% of increase to the initial costs. Thus, through the presented study, the execution of a building with stake foundation, for a project robust to progressive collapse, demonstrates to be feasible. However, further studies should be carried out in order to increase the quantity and quality of the results found.
Reação álcali-agregado: proposta para método de inspeção em edifícios prontos e diagnóstico rápido em elementos de fundação.
(Universidade Católica de Pernambuco, 2021-12-18) Maranhão, Amanda Gabriela Dias; Silva, Angelo Just da Costa e; Silva, Aluízio Caldas e; Monteiro, Eliana Cristina Barreto
The pathological manifestations occur due to a set of factors. Among them, we can mention the environment to which the structure is exposed, the materials used to make the concrete, poorly designed projects, as well as the poor execution of the structure and lack of periodic maintenance. Among the deleterious manifestations known in concrete structures, the alkali-aggregate reaction (AAR) stands out, which occurs due to the occurrence of chemical interactions between the mineralogical compounds of the reactive aggregate with alkali hydroxides of cement and the suitable medium for the reaction to occur. That is, mainly in building foundations. It is known that the pathological condition is irreversible, resulting in expansive products, which generate cracks, movements and can compromise concrete structures. Although studied in Brazil since 1960, in Pernambuco, with the collapse of the Areia Branca Building (2004), it moved the studies in building works in the metropolitan regions of Olinda, Recife and in other regions of the country. Still, there is no single method of inspection in finished buildings and quick diagnosis for foundation elements. To reduce costs and time in the identification and monitoring of this pathology, current research proposes a protocol for the rapid identification of AAR in foundation elements of multi-storey buildings.
Análise comparativa da produtividade dos sistemas construtivos de alvenaria de vedação: bloco cerâmico e bloco de gesso.
(Universidade Católica de Pernambuco, 2019-05-23) Oliveira, Bárbara Paniquar de Souto; Silva, Angelo Just da Costa e; Nogueira, Fernando Artur; Paliari, José Carlos
The quest for increasing productivity in construction companies is evident due to the need of improving efficiency, reducing costs and improvement of final product quality. These needs can come from good knowledge and management of productivity on the site, not to mention the reduction in the consumption of project resources. This thesis aims to make a comparative analysis of productivity indices between execution of masonry, through a case study in six construction sites in Pernambuco, all from a big construction company, with emphasis on wall execution in ceramic block and gypsum block. Therefore, two main construction indicators were observed: Productivity Unitary Ratio and Loss of Labor Productivity. After cumulative Productivity Unitary Ratio for the 6 work sites the obtained result for ceramic block walls was an average of 0.47 person-hours /m², while for gypsum block wall the average Productivity Unitary Ratio was person-hours /m². This way, the gypsum block showed a better efficiency when compared to ceramic block through the analysis of loss of labor productivity, 10% and 6%, respectively. It was possible then to conclude that the gypsum block presented a 15% higher productivity when compared to the ceramic block on wall execution.
Discussão sobre a caracterização da reatividade de agregados graúdo utilizados na fabricação de concretos.
(Universidade Católica de Pernambuco, 2021-02-19) Marins, Jéssica Ferreira; Silva, Fernando Artur Nogueira; Silva, Ângelo Just da Costa e; Azevedo, Antônio Augusto Costa de
The alkali-aggregate reaction (AAR) is a deleterious chemical reaction that involves sodium and potassium ions, mainly from Portland cement, some mineral phases that may be present in large aggregates or small amounts that in the presence of water can cause expansions in concrete structures. Knowing the mineralogy of the aggregate is fundamental, because avoiding the use of reactive aggregate prevents the appearance of this pathological manifestation. The objective of this work is to make a comparison between the different test methodologies for determining the expansion of concrete prisms by the accelerated method, Brazilian standard NBR 15577- 7:2018 with RILEM AAR-4.1:2016 and modified AASHTO T 380:2018. The methodologies proposed by NBR and RILEM are very similar, differing only in the amount of aggregates and cement consumption. The method proposed by AASHTO differs in the packaging and time of the test. As the intention of this research is to evaluate the conditions of the test environment the same mold size was maintained for all evaluated methodologies. For the execution of all tests it was used a reactive large aggregate and innocuous small aggregate. The specimens tested by the NBR and RILEM methods pointed out that the large aggregate used is reactive at first reading, where the dimensional variation of the prisms was greater than 0.03%, the limit proposed by both standards. The prisms behaved in relation to the very similar expansion. The methodologies proposed by NBR and RILEM last 20 weeks, with an interval of 5 weeks for each reading. Analyzing the results found in the test that was obtained with the packaging environment as proposed by AASHTO T380: 2018 it is possible to conclude that the speed of occurrence of the expansion is greater than in the other methodologies. This is because the test conditions are very aggressive. This lasts for 56 days, readings are taken with small intervals between ages. After conducting the proposed tests and analyzing the data found, it is possible to verify that all the studied standards fulfill the main objective of characterizing the aggregate in terms of alkali silica reactivity.
Análise comparativa das simulações computacionais e medições em campo dos critérios de desempenho acústico em vedações verticais internas e vedações horizontais.
(Universidade Católica de Pernambuco, 2019-12-10) Rezende, Emanuela Carvalho Lobo; Silva, Angelo Just da Costa e; Silva, Paula Maria Wanderley Maciel do Rêgo; Silva, José Jéferson do Rêgo
In urban areas and large cities, numerous pollution problems have negative impacts on the environment and human health. Noise pollution is one of the problems that are potentially being treated by society due to the impact caused both in terms of comfort and the health hazards they cause. To promote better use and occupation of housing buildings, the acoustic quality of the environments has been sought through modifications to consolidated building systems and improvements in building technology. In this context, the NBR 15575, named as the performance standard, emerges, linking the performance of housing buildings to the aspects of comfort, safety and durability. The standard presents criteria to be met and the manner in which such parameters should be measured. Since acoustic performance is one of the requirements of the standard, the aim is to attenuate sound between environments, whose objective has involved not only builders, but also designers, material suppliers and users. Acoustic forecasting models from computational simulation (SC) has been the tool used to evaluate the acoustic behavior of the property, 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 internal vertical sealing systems (SVVI) and horizontal sealing systems (SVH). Comparative analysis of 75 SVVI SC and MC data showed that more than 50% of the simulation data showed values compatible with the 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 ±2dB. Removing discrepant data, due to the limitations of the program, this percentage reaches 69%. For the 228 SVH data, of which 116 were for SVH-RA and 102 for SVH-RI, the comparative study showed a 38% acceptability between SVH-RA measurement and simulation and 46% for SVH-RI. This acceptability refers to the values within the ±2dB range of the afore mentioned uncertainty. The data also showed variation between SC and MC, sometimes presenting a larger SC, sometimes a larger MC. The expectation was that the results would converge, but where situations of MC values greater than SC occurred, it is concluded that the field will enjoy better performance than the minimum of the projected standard. The contrary confirmed that unforeseen factors in the field, construction failures, seals etc. compromise the expected performance. It was also verified, through variation of the input data, that the fidelity to the technical specification of the projected systems reproduces reliable values, and the opposite results in the fragility and discrepancy of the data. In general, the results of the comparative analysis point out as positive the use of computer simulation, since part of the percentage out of the acceptability in this study represents uncertainty in the measurements, being, therefore, the simulation an effective instrument of forecast and useful in the search for acoustic quality residential buildings.

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