Browsing by Author "Maia, Lino"
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- A bibliographic review of concrete obtained by alkaline activation and the specific case of the municipal solid waste incineration slagPublication . Ventura, Sebastião; Maia, LinoThe present bibliographic review work focuses on the approach and study of historical processes of slag resulting from the incineration of municipal solid waste, namely: An introduction to the history of Roman civilization and its building habits in the region of Pozzuoli, its engineering and architecture; Alkali-activated ligands, their Zeolitic compositions, geopolymers, chemical reactions and their crystalline phases, amorphous materials and the composition of aluminosilicates; Chemical and structural characterization of alkaline-activated materials and elements; Hybrid cements considered binders containing a percentage of OPC and another percentage of an aluminosilicate precursor and activated alcaline; Origin and treatment of municipal solid waste as well as incineration processes; Hybrid cements containing municipal solid waste incineration slag; An approach to the alkali activation of ligands with slag from municipal solid waste incineration. Finally, a conclusive top-down analysis of these issues.
- BIM methodology, a new approach - Case study of structural elements creationPublication . Maia, Lino; Mêda, Pedro; Freitas, João G.BIM methodology has gained great importance in the construction industry. This methodology introduces noteworthy changes in the way as building design, construction and maintenance are traditionally managed. This paper explores and evaluates the advantages and disadvantages of BIM methodology application on the preparation, revision and coordination of designs, as well as the analysis of the computational tools available. Using the Revit software a building (laundry of a hospital) was modeled in BIM based in the design drawings carried out by using the traditional methods in CAD 2D.
- BIM model to support O&M tasksPublication . Carvalho, Ana Thereza; Calejo, Rui; Santos, José; Maia, Lino: Technological evolution and BIM have changed the design development process in the construction industry. The operation and maintenance (O&M) phase requires building information throughout its service life, which was previously paper based, making it difficult to carry out maintenance activities. BIM assists in the management, storage, and digital sharing of information generated. However, only part of the information generated is required for the maintenance phase of the building. Although a subset of the IFC schema already exists to describe the data exchange between the BIM model and maintenance software, the data are generic and not well defined according to each the element source of maintenance (ESM). Therefore, through a literature review of existing studies on the use of BIM to support O&M processes, this paper aims to design an information flow to integrate maintenance information into the BIM model. The information is based on six main maintenance acts (inspection, cleaning, proactive measure, correction, replacement, and terms of use) and organized in an external sheet. The building will be divided into ESM according to its function in the building to facilitate the maintenance information flow between sheets and the BIM model.
- Comparative Analysis of the Execution between Conventional and Self-Leveling Screed: Case Study in a Vertical Condominium in Campina Grande - PBPublication . Mendonça, Fernanda Calado; Barbosa, Felipe Brasileiro; Maia, LinoCivil construction is a very competitive industry, and it is continuously searching for viable alternatives and good results that can be applied in a short-term period of time. This work was carried out based on a case study, in a construction site that executed the conventional screed method in multi-family buildings located in the city of Campina Grande - PB. The objective of this work was to analyze and compare the conventional and self-leveling screed method, highlighting the advantages and disadvantages, as well as the economic feasibility for this case. Through observation and recording of data performed in real time during the execution of the it was possible to catalog and prepare documents for the development of the analysis. It was noticed that the self-leveling screed, when compared to the conventional is an alternative with very satisfactory results, both regarding the time of execution and its economic viability.
- Comparison of response models from full, fractionated and small central composite design of experiments in cement-based mortarsPublication . Cangussu, Nara; Matos, Ana Mafalda; Maia, LinoExperimenters often do not have adequate time, resources or budget to carry out large number of experiments. DOE based in factorial designs are a powerful tool for designing and optimizing advanced cement-based materials, such as high performance self-compacting mortars, where many constituents raw-materials are employed (binder phase, granular materials, and admixtures) and several engineering as aesthetics requirements. The objective of this work was to compare response models from full, fractional, and small Central Composite Design of experiments applied to mortars properties.
- Concrete with partial replacement of natural aggregate by PET aggregate—An exploratory study about the influence in the compressive strengthPublication . Figueiredo, Filipe; Silva, Pamela da; Botero, Eriton R.; Maia, LinoThe expansion of cities contributed to the problems related to the accumulation of waste and lack of control over its management, there are still around 2400 dumps or uncontrolled landfills in Brazil. There is a large volume of polyethylene terephthalate (PET) improperly discarded. In turn, the construction industry has been looking for sustainable ways to produce concrete. This work deals with the analysis of the replacement of PET as a fine aggregate in concrete in the proportions of 5% and 15%. PET particles pass more than 75% in the 2.36 mm opening sieve and have more than 99% of their particle size retained in the 0.15 mm opening sieve. Concrete properties, compressive strength, tensile strength, water absorption and void ratio were evaluated and compared with the reference mix. In total, 45 specimens cast in concrete were used to complete the experiment. The results obtained showed that mixture compositions that incorporate PET as fine aggregates decrease compressive and tensile strength, increase water absorption and void index. The results obtained showed that blending compositions that incorporate PET as fine aggregates decrease compressive strength in about 14%, decrease tensile strength in about 7–11%, increased the void ratio in almost 20% and increased the water absorption in about 30%.
- Developing a commercial self-compacting concrete without limestone filler and with volcanic aggregate materialsPublication . Maia, Lino; Neves, DianaSelf-compacting concrete (SCC) is a concrete with enhanced fresh properties that allows pouring without external compaction. Its advantages also are extended to good segregation resistance, higher homogeneity, lower permeability, which among others, lead to a product with higher durability. Although the SCC advantageous, up to the begin of this research program, never a SCC composition was been produced and commercialized in the Madeira Island. This paper describes the experimental program carried out on the development of a commercial SCC composition, using the materials currently available in the local market of Madeira Island. Moreover, it aims to contribute to the establishment of a methodology that leads to optimized compositions to satisfy the performance requirements of the commercial SCC compositions. Several SCC mix compositions were tested, studies being initially carried out on pastes and mortars. As limestone filler is not currently available in the local market, the powder content was increased by incorporating fly ash, being the water-to-cement ratio kept low by using a superplascyzer and a plasticyzer. All the aggregates were from volcanic origin; the fine sand was from the ocean and the coarse sand, fine gravel and coarse gravel were crushed. At the end, an optimized SCC composition was validated in real/commercial conditions: it was produced in a ready-mix concrete plant, transported and applied in a real structure wherein self-compacting properties were required due to high reinforcement content. Since no markedly changes were introduced from production up to casting, results were considered satisfactory. Consequently, the concrete plant decided to commercialize the SCC composition in the Madeira Island market.
- Durability in alkaline-activated materials a review on the state of the artPublication . Ventura, Sebastião; Maia, LinoThe present work on durability in materials obtained by alkaline activation (AAM), in state-of-the-art review format, is structured as follows. (I) -The concept of alkali activated materials-composition-performance; (II) - The prediction of the useful life of AAM-methodologies and planning; (III) - The durability and properties of Engineering-mechanical tests-standards of specifications and tests (IV)-Degradation processes of Chemical Matrix-resistance to sulfates (SO4-²), acids (HCl), (H4²2SO4) (HNO3), (H3PO4), (HF), (H2CO3) and sea waters; (V) Degradation processes by mass transport - permeability, porosity, corrosion, carbonation, efflorescence and ice-thawed.
- Durability of concrete with alkali-activated materials, a short literature reviewPublication . Ventura, Sebastião; Maia, LinoThe alkali-activated materials are being understood as the best chance to replace the Portland cement to become the concrete industry greener in terms of CO2 emissions. However, these alternatives binders face challenges, among others related to durability. The present work regards to a short literature review about the durability in concrete produced with binders that are alkali-activated materials.The mechanisms of degradation are discussed, namely due to acid attack, capillarity, carbonation, permeability , porosity and steel corrosion. Comparison to the concrete permeability, porosity and steel corrosion. Comparison to the concrete that used Portland cement as binder is frequently used.
- Environmental Analysis of the Incorporation of Sugarcane Bagasse in Medium Density Particleboard Panels through Life Cycle AssessmentPublication . Cangussu, Nara; Vieira, Maria Luiza C.; Maia, LinoThe growth of civil construction and agroindustry, resulting from population growth, caused an increase in the demand for non-renewable resources and for the exploitation of natural resources. Consequently, it caused a greater generation of waste, causing the current scenario to require alternatives for the reuse of these materials. Particleboard panels, for example, used in civil construction, can add value to waste or materials of low acceptance, such as thinning wood, mechanical wood processing waste or agro-industrial waste. Thus, this study proposed to analyse the life cycle of the sugarcane bagasse, considering the stages of extraction of materials and energy resources until their final disposal. This study aimed to compare impacts generated by the production of particleboards panels produced with wood from plantations (pine) and with the sugarcane bagasse. As a result, a better environmental performance was obtained from the panel composed of sugarcane bagasse, as it generated lower environmental impacts in all impact categories studied. The benefits range from the reduction in waste disposed of in landfills, which increase its useful life, the lower demand for reforestation, with steps that generate atmospheric emissions and degrade the soil.