Luísa Andréia Gachet-Barbosa

Effects of Consumption of Cement in Mechanical Properties of Lightweight Concrete Containing Brazilian Expanded Clay

Concrete is one of the oldest building materials known to humankind. From 1824, with the advent of Portland cement, concrete assumed a prominent place among the construction materials, due to large amounts of strength, durability and versatility it offered compared to other products, allowing the molding of various forms architectural. Until the early 80s, the concrete remained only as a mixture of cement, aggregates and water, however, in recent decades, due to the development of new techniques and products, the concrete has been undergoing constant changes. The concrete with lightweight aggregates have been used since the beginning of the last century, with low values of density (< 2000 kg/m3), demonstrating the great potential of using this material in several areas of construction [. With the objective of analyzing the influence of the consumption of cement in conventional concrete and light, were molded, tested and compared body-of-evidence containing two different amounts of cement consumption: a) 350 kg/m3 and b) 450 kg / m3. The results were compared with those obtained by other researchers, as well as with [ and [.

Production of Self-Compacting Concrete Using Rock Breaking Waste Residues

Waste residues derived from the breaking process of rocks have been many times inadequately discarded on the environment generating an environmental passive. The residues could be used in the production of self-compacting concrete (CAA) providing more sustainable constructions. To study different CAA mixtures the following tests have been performed in the fresh state: Water Absorption, L - Box, V - Funnel and Slump Flow Test. For the evaluation of mechanical performance, the concrete Compression Strength Test, Flexural Strength Test and Tensile Strength by Diametric Compression Test have been performed in the hard state. Technical and environmental viability in the addition of this type of residue for the studied percentages have been verified.

Evaluation of the Behaviour of Mortar with the Addition of Rubber

This research studies the mechanical behaviour of mortars with the addition of increasing percentages of rubber from used tires. This type of mortaris usually destined to wall coating and components, in which case it should present the required properties. In this study natural sand has been partially substituted by fine aggregate from recycled rubber and the hard state properties have been evaluated. The results obtained indicate the technical viability of the substitution. With the use of recycled aggregate the quality of the mortars has been preserved, which shows the possibility to properly adequate the destination of discharged rubber aiming to minimize environmental impacts and to reduce natural sand extraction from non renewable sources.

Estudo do reaproveitamento de resíduos de construção em concretos empregados na fabricação de blocos

The use of construction and demolition waste (CDR) comes as an alternative for recycling, for costs reduction and for raw material. The CONAMA Resolution 307 (National Council for the Environment) establishes that all cities should find an environmentally correct destination to CDR. In this research the mechanical properties of the concrete containing CDR were analyzed aiming its use in the production of concrete blocks. Here, increasing percentages of aggregates of CDR with the same granulometry an substitute the natural aggregate, and then concrete blocks were molded. Tests were then performed in order to determine the compression strength according to NBR 12118:2007, at ages of 14 days and 28 days. It was noticed that the values resulting from the compression strength test were also influenced by the increasing substitution of CDR percentages to the mixture. This research discusses the great potential of using this material in substitution to the natural aggregates used in the production of concrete based materials such as blocks.

Contribution from the Use of Alternative Materials in Concrete for Accessibility on Sidewalks

This study aims to address the question of accessibility on sidewalks in accordance with Rule 9050 of the Brazilian Association of Technical Standards (ABNT NBR 9050:2004) and analyze the feasibility of using alternative materials (steel fibers, construction waste and rubber) to produce Interlocking tactile concrete paver. It was performed an experimental dosage of concrete with 04 specimens: reference, with steel fiber, with rubber and with steel fiber and construction waste. The pavers molded with conventional concrete and with the addition of alternative materials were tested as for compression strength and water absorption and the results were satisfactory, meeting the specifications of the Brazilian standard.

Interlocking Tactile Concrete Paver with Addition of Steel Fibers

This work deals with the investigation of the performance of concrete with addition of steel fibers for production of interlocking paver. Was accomplished an experimental dosage of concrete and the addition fibers contents were 40Kg/m3, the molded pavers with conventional concrete and with addition of steel fibers and were accomplished tests of compression strength and water absorption, through the preliminary results, we verified that are satisfactory and achieve the specifications of Brazilian standard (ABNT NBR 9781:2013) and some international (ASTM-C936:1996 e CSA A231.2:1995).

Management of Gypsum in Construction Site - Case Study

The waste generated by the construction sector have increased significantly, becoming an increasing problem, since most of this waste is deposited irregularly, not giving its proper disposal. Such waste, if not disposed properly contribute to environmental degradation, affecting not only the environment, but also, the quality of life. The gypsum products are among the wastes of this activity. Gypsum is a material that has many applications in the construction and generates significant volume of waste that most often is not reused, and usually has its final destination in landfills or dumps. The objective of this research was check on a construction site what kinds of alternatives are used for the management of waste gypsum in the building. The plaster can be recycled easily, being used in the production of cement. For the realization of recycling, theres the ATT - Transshipment Areas and Screening, in which they receive the plaster and other residues to prepare them for their industrial reuse. This way you can properly allocate the waste gypsum, without causing environmental damage and promoting better management of the construction site. Keywords: recycling of gypsum, management of construction site.

Implementation of Environmental Management on a Construction Site

The Construction sector in Brazil has increased significantly, and the waste from these activities are becoming an increasing problem, thus receiving special attention, especially in recent decades, since a lot of them are deposited irregularly without proper disposal. Such waste, if not disposed properly, help environmental degradation, affecting not only the environment, but also, the quality of life. The objective of this research was to evaluate procedures that contribute to the development of sustainable management of construction waste, aiming to reduce, reuse and recycling of materials. Deploying a methodology for sorting waste more suitable for the work and for the monitoring and control suitable for final disposal, able to meet the legislation.

Mechanical Evaluation of Concrete Containing Lightweight Aggregates

Since the invention of modern concrete, in the mid-nineteenth century until the early 80s, the concrete remained a mixture of aggregate, cement and water, with no major innovations that significantly alter the performance of its properties. But in recent decades, concrete technology has undergone tremendous development that has occurred due to the development of techniques and equipment for the study of the concrete and the use of new materials.The concrete with lightweight aggregate have been used, mainly due to the low values of density, thus demonstrating the great potential of using this material in several areas of construction [.With the objective of analyzing the influence of the consumption of cement in conventional concrete and light, were molded, tested and compared body-of-evidence containing two different values of cement consumption. The values were compared with those obtained by other researchers, as well as with the ABNT NBR 6118:2003 [ and ACI 213R-03:2003 [.

Concrete Slab Value Stream Mapping of Brazilian Residential Buildings - a Lean Construction Study Case

Sustainable research inconstruction environments has being weakening more interest for theconstruction sector, due to visible wastes during the constructive processes.In this scenario, high costs and consumptions of unnecessary materials in the work activities are inserted also, which generate waste and customer dissatisfaction.The real knowledge of this situation can be present with the Lean Thinking concepts application. The scientific initiation research identifies, from the Value Stream mapping application, the structural elements processes and all the waste detected in their observation. This study case shows how to apply the lean principles, and presents your informally application in the Brazilian Company specifically. This study has an investigative character, and considers that the company applies just a part of the Lean principles. Therefore, the paper has as objective to present the application of VSM and the preliminary sustainable analyses too.