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The concrete industry accounts for a significant amount of CO2 emissions worldwide. One approach to counter this issue includes material reduction of structural components via the use of nonmetallic reinforcement, such as carbon, glass and basalt fibre reinforced polymers. On the one hand, non-metallic reinforcement. However, as its environmental impact has not been sufficiently investigated yet, a Life Cycle Assessment of the production phase is presented within this paper. In a first step, the environmental impact of the sole various reinforcement components and types is compared to each other per mass, per tensile or rather yield strength as well as density unit, at which an environmental disadvantage of especially carbon-fibre reinforced polymers is apparent in most cases. In a further step, a focus is put on applying the environmental data of carbon-fibre reinforced polymers to a pedestrian bridge, which is finally compared to a conventionally reinforced concrete bridge and a steel bridge with similar boundary conditions. The latter results indicate that an adequate application of carbon-fibre reinforcement in structural components has the potential to lead to designs of less environmental impact in comparison to conventionally reinforced pendants. [ABSTRACT FROM AUTHOR]

The paper describes an assessment of concrete in terms of environmental impacts in relation to the utilization of recycled materials. The article includes a short summary of the literature search on evaluation methods for environmental impacts and on recycled and secondary materials. The environmental impacts of several concrete mixtures were calculated. The reference concrete mixture containing only cement as a binder and only natural aggregate was compared with other mixtures containing recycled and secondary materials as a binder or aggregates. Some of these concrete mixtures were then compared within the whole structure. Variant design of a simple structure was performed, whereas the variants differed in the concrete mixture. These variants were then evaluated in terms of environmental impacts. [ABSTRACT FROM AUTHOR]

Life cycle assessment (LCA) in the building sector has become a widely used method for quantifying environmental impacts of a building over its entire life cycle. Currently, however, no standardized procedure exists for considering refurbishment measures. In addition, the LCA, according to the European standard EN 15978, is limited to building level only. This paper shows how a methodological LCA framework of refurbishment methods can be applied at three levels: single building, neighbourhood, and municipality. Initially, the proposed methodological approaches are introduced while the framework rules are defined for each of the three levels. The system boundaries of the LCA differ regarding the assessment levels within the given methodology and are adapted accordingly. In addition, the three levels of assessment are defined by the accuracy of measurement results, and data requirements, as well as by the specific value of the calculations and the ownership of the building stock. The assessment levels provide a specific quality and quantity of environmental indicator results. Thus, the complex interrelationships of the assessment levels are shown. The developed framework for the environmental assessment of refurbishment measures provides comparability at the building level. At the neighbourhood level, emissions from refurbishment measures are compared with the reductions of emissions through heating energy demand. Ultimately, the potential of refurbishment measures at the municipal level can be identified on a large scale and used as a decision-making tool. [ABSTRACT FROM AUTHOR]

The construction and transport sectors both have a substantial impact on the environment. The construction, maintaining and renovating of roads involves both these sectors and the environmental impact of this work can be reduced. The basic principle of a circular economy is to close material loops and so retain the highest utility, quality and value of products, components and materials as possible. An important question in this respect is how to qualify and quantify material flows. Material and project passports seem to be part of the solution to improve insights and sharing information on quantities and qualities of materials used in construction projects. This paper has used a literature study on material passports and has taken into account current project management software used by a municipality, in order to share a framework for organising and collecting road construction data. Furthermore, various scanning equipment and procedures were employed onsite in an experiment in collecting actual road data. This resulted in a large amount of different data files that have been interpreted and incorporated into the existing database structure of the municipality. The insights gained may help other researchers, principals and contractors in the road construction industry in collecting and storing reliable data necessary to renovate roads circularly. [ABSTRACT FROM AUTHOR]

The construction industry produces several negative environmental impacts. To promote solutions that reduce these negative impacts, it is crucial to increase awareness among all parties involved in the supply chain. Currently, certification protocols, environmental labels and declarations are the most common tools for promoting sustainability in the construction industry. However, these tools are generally non-mandatory and require specific competencies to thoroughly understand and interpret their outputs, especially for non-specialized users in sustainability assessment. This paper presents a tool for visualizing environmental impacts directly through a Building Information Model, by assigning different colours to model objects according to their environmental performances. Understanding environmental performances data is thus more accessible to non-expert users. Unlike several BIM-LCA integration studies that primarily focus on the needs of designers, this contribution considers the perspective of manufacturers. The developed tool focuses on building products and has been carried out with the Autodesk Revit BIM authoring platform and its VPL-based Dynamo plug-in. Through the combination of 3D models and histograms, the tool facilitates manufacturers to visualize with real-time updates which phase of a product life cycle requires sustainable innovation, which sub-components or process determine the major environmental impacts and calculate the environmental cost indicator of a product. [ABSTRACT FROM AUTHOR]

The growing importance of a circular economy also holds possibilities for concrete. Some of the principles of circularity, like the re-use of "waste" as secondary raw material and the optimisation of the design with regards to lifespan, environmental impact and re-use, can be applied. Several technological innovations in this domain are in an advanced stage of development. However, the transition from research to full commercial applications is held back, mostly due to the absence of documented experience and the lack of a technical framework (prescriptions). In order to accelerate the adoption of new technologies, the Belgian Building Research Institute (BBRI) started the project "Circular.Concrete". In this paper, the results are presented of validation tests regarding 1) smart crushing technology, 2) the carbonation of recycled aggregates, 3) concrete using only recycled aggregates and 4) the use of alternative binders and supplementary cementitious materials. [ABSTRACT FROM AUTHOR]

There have been numerous researches focusing on the alternatives to conventional concrete regarding environmental benefits and trade-offs. For this purpose, nowadays, the Life Cycle Assessment (LCA) is widely used. Until now, LCA results of conventional and green concretes have shown some limitations, and this paper focuses on addressing them. Firstly, the researches have been mostly based on a small number of concretes, which can limit the possibility to quantify the range of emissions for different set of assumptions. The second one is regarding the appropriate selection of functional unit where a divergence between different researches is visible. Moreover, it has been recognised that the criteria involved in the investigation of transportation might lead to the variation of results. Also, inventory allocation has to be assessed in detail to reach adequate distribution of the environmental impact of the concrete during its life cycle phases. Finally, CO2 uptake of the concretes throughout the life cycle should be considered and applied adequately to have representative results of overall CO2 emissions. It is expected that the differences will depend on construction practices among the countries where the researches are executed. Also, the results will surely vary between different system definitions when LCA is applied. [ABSTRACT FROM AUTHOR]

In industrialized countries, most of the reinforced concrete (RC) structures and infrastructures have more than 40 years, since they were built around 1960 − 1980, and were designed for a service life of 50 years. Consequently, in the next years, the number of structures and infrastructures that will need to be repaired will steeply increase. Several techniques, characterized by a different durability, environmental impact and economic impact, are available for the repair of a reinforced concrete structure damaged by the corrosion of reinforcement. To help the designers in the choice of the most suitable one, a preliminary assessment of the condition of the structure is essential, aimed at diagnosing the causes of deterioration, the extent of damage, i.e. the extent of corroding reinforcement, and its evolution in time. An approach, with a wide consensus, for the evaluation of the extent of corroding reinforcement is available for carbonation-induced corrosion, whilst it is still lacking for chloride-induced corrosion. In this paper two approaches for the evaluation of the extent of corroding reinforcement for a RC structure subject to chloride-induced corrosion are presented and compared, showing similar results. These approaches can be useful to properly plan a restoration intervention as well as to assess the reliability of the recently proposed model for service life design. [ABSTRACT FROM AUTHOR]

Electricity storage technologies in buildings are evolving, mainly to reduce their environmental impact and to improve self-sufficiency of buildings that produce their own energy through Building-Integrated Photovoltaics (BIPV) installations. To maximize self-consumption - minimizing the import of grid electricity - photovoltaic (PV) systems can be coupled with a hydrogen storage system converting the electricity to hydrogen by electrolysis during the summer season - when the on-site production is higher - and employing it during the winter season with fuel cells. This study focuses on the sizing constraints of solar hydrogen systems at building-scale using an innovative research-centre that will be built in Fribourg (Switzerland). It presents four stories and a mix-usage (office spaces and research facilities areas) and multi-oriented PV installation in order to produce enough electricity to achieve at least 50% of electricity self-sufficiency ratio. Using the PV production, this study aims to optimise the sizing of a hydrogen storage system allowing to reach the required self-sufficiency ratio with the lowest environmental impact possible. Ultimately, the global energy and financial efficiency of the system will be analysed. [ABSTRACT FROM AUTHOR]

INTERACT is an international research and innovation project which boosts the emergence of Energy Communities as one crucial building block to achieve Positive Energy Districts. It is designing an optimal organization and structure for Energy Communities based on success-factors of existing PED/PEN approaches, stakeholder needs and motivation, the available technologies, and a holistic LINK-based architecture. Technological and market-related solutions are delivered that maximize the benefit for the environment and society, considering the current legal framework and available business models. The project will develop a roadmap for the Energy Community's secure and reliable embedding into the power system structure, focusing on two pilot regions, a green-field project in Sweden and an existing municipality in Austria. The holistic architecture is used to ensure the integrity of the solution by harmonizing all interactions within the Energy Community itself, between it and the market, and the European power system. Its standardized and flexible structure allows the straightforward application of the roadmap to perfectly meet the diverse necessities of local communities, thus supporting the large-scale roll-out of the new control paradigms. [ABSTRACT FROM AUTHOR]

Low density of the light-weight cement blocks offers an advantage in terms of dead load reduction, which is advantageous in structural design-reduction of size and numbers of loadcarrying structural components is possible. Production of cement blocks, however, generally requires Ordinary Portland Cement (OPC) which creates harmful environmental impacts. Utilization of waste as alternative raw materials for cement production is a route to alleviate the problem. This research aims at synthesizing eco-friendly cement-like material for production of light-weight cement blocks. The cement-like material were prepared from eggshells, cockleshells, and rice husk ash (RHA). With high content of calcium oxide and silica, eggshells and cockleshells are potential sources of calcium, whereas RHA is a good source of silicon. Additionally, a fuel-efficient solution combustion technique was employed in synthesis of the cement-like material. Phase identification analysis of the synthesized powder indicated that tri-calcium silicate (C3S), di-calcium silicate (C2S), tri-calcium aluminate (C3A), and tetra-calcium alumino ferrite (C4AF), which are main constituents of OPC, were obtained. To fabricate eco-friendly light-weight cement blocks, the synthesized cement-like material were mixed with cement, water, and additional RHA and cast into blocks. The optimal compressive strength and density of the cement blocks were in comparable range with the standard light-weight concrete defined by Thai Industrial Standards Institute (TISI) and American Concrete Institute (ACI 213,2001). With jute fiber reinforcement, enhanced compressive strength of 20% was achieved, while elimination of spalling after compression test was clearly evident, implying a more ductile failure. [ABSTRACT FROM AUTHOR]