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World history tells us that construction has always existed to meet the immediate and basic needs of man, and, in this time of rapid growth, did not take into consideration construction techniques and environmental preservation. This paper aims to present investigation and diagnosis at the stage of site construction, exploring the environmental impacts caused by construction site, with exposure of some interventions to minimize this effect, integrating the concepts of sustainable construction. Given the historical background of continued environmental degradation caused by human needs, which resulted in serious risks to society, and knowing that more than 60% of solid wastes generated in urban centers are from the construction site, the need arises to develop techniques and solutions to mitigate these impacts. Structure of the research/approaches: The paper is structured in four parts: description of an evolutionary history regarding environmental concern, a sustainable construction issue approach, surveying interference at the stage of site construction, and a case study focusing on environmental sustainability during the site construction phase of an enterprise. Contributions: The characteristics of a sustainable building interfere directly in the relation between man/environment with issues that can be minimized when designing a project, which should be applied from the construction of a building to the end of its life cycle. A sustainable enterprise is not defi ned not only by environmental and social benefi ts in its use and operation but also in its construction.

Concrete is a major construction material that produces high levels of carbon dioxide in its manufacturing process. Hence the construction sector is responsible for relevant environmental impacts. This justifies the need to find materials as green and ecological alternatives to common Portland cement. Geopolymers represent the most promising alternative due to its proven durability, mechanical and thermal properties. This study investigates the effects of solid-to-liquid and alkali activator ratios on the synthesis of slag-based pure geopolymer and their relation to the geopolymerization process. Two activating solutions were used: a) a mixture of sodium hydroxide, sodium silicate, and water; and b) a mixture of potassium hydroxide solution, potassium silicate, and water. As precursor material, ground blast furnace slag was used. Precursors and activators were mixed with solid-to-liquid ratios in range of 1.5 to 2.2. In the first stage of the study, the mechanical properties were evaluated for each activating solution. In the following stage, different formulations, with variations in the water percentage and solid-to-liquid ratio were tested for mechanical properties and SEM observations. Test results indicate that the resulting geopolymer has the potential for high compressive strength and is directly affected by the composition of the activating solution. It can also be observed that compressive strength was affected by solid-to-liquid ratio and % of water added to the mixture, and strength increased with ageing day.

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Proposal: This paper presents concepts of sustainability embedded in environmental certifications applied to building construction. The article addresses the importance of certification and the benefits to the environment coming from its deployment. Building constructions consume many materials, emit many gases, and use a lot of energy and water, what point to the extreme importance of developing processes that aim to conserve natural resources, using them optimally. It is necessary to identify actions needed to integrate all the steps involved in the project life cycle, including entrepreneurs, developers, builders, manufacturers, managers of enterprises, users and society. Among these reasons, arises the certification process of the project, which helps minimizing the environmental impacts using natural resources in a more conscious way. This paper aims to present the concepts of an environmental certification focused on construction, compare two of these systems: LEED (Leadership in Energy Environmental Design) and HQE (Haute Qualité Environnementale), its application methodologies application methodologies, the phases in which they apply during the life cycle of an enterprise, and their benefits. Research Structure / Approaches: The article is structured in three parts: a brief review on this topic historic evolution; a description of the main features of the existing certification procedures; and case studies covering a LEED certified building and another with HQE certification. Contributions: The sustainable construction is based on actions that enable the building construction to encounter or create solutions for ecological problems, using technology, selecting the materials and their suppliers, creating buildings that meet the needs of their users and, also, the environment.