3,685 research outputs found
Prefabrication as large-scale efficient strategy for the energy retrofit of the housing stock: an Italian case study
In this work a multi-story residential building located in Cinisello Balsamo, near Milan, was considered as case study for the application of two new prefabricated building systems for the energy retrofit. The first one, developed within EASEE, a European project funded by 7th Framework Program, consists in a preassembled insulated panel for the retrofit of facades, based on two TRC thin precast layers rigidly connected to an EPS core. The panels can be easily applied on the external side of existing facades without the use of scaffoldings, providing an additional efficient insulation as well a new external cladding. The second one consists in a preassembled timber panel for existing pitched roofs. The process includes the substitution of the existing roof with modular integrated panels with a high content of recycled materials that can be easily fixed on the existing structures (timber frames, concrete, masonry, etc.). The combination of the two prefabricated construction systems, applied on the case study, allowed the reduction of the building energy demand by 82%
Intelligent precast construction systems : project, realization, maintenance technology for the optimization of the environment and economic sustainability
RESUMEN: Esta tesis doctoral propone una tecnología de intervención racionalizada basada en un sistema de paneles prefabricados innovadores orientados a la optimización de las prestaciones tanto energéticas como estructurales de edificios existentes con entramado resistente de hormigón armado. La metodología consiste en revestir el edificio con módulos prefabricados de altas prestaciones térmicas, referidos a la fachada mediante elementos metálicos directamente instalados sobre esta. La optimización de su desempeño estructural, a base de crear un comportamiento tipo caja, se materializa por el vertido in situ de un hormigón aligerado en la cavidad resultante entre la nueva fachada (paneles prefabricados) y la del edificio existente. Además, la nueva tecnología permite integrar, desde la fase de instalación del sistema, sensores para monitorizar el rendimiento del edificio durante su ciclo de vida. Con este nuevo sistema se pretende reducir el tiempo de materialización de la intervención, los costes de mantenimiento y prevenir posibles daños irreversibles al edificio.ABSTRACT: This doctoral thesis proposes an innovative building renovation system of novel precast concrete (PC) modules devoted to the optimization of the energy and structural performance of the existing RC buildings. It consists in covering the façade with the PC modules with high thermal performance, by means steel elements directly installed on the building. The structural strengthening is assured by a cast-on-site light-weight concrete in the resulting cavity between the novel and the exinting wall. Moreover, the system project considers the possibility to insert into the stratigraphy, performance monitoring devises for the diagnosis and building automation already during the construction phases and inspect them anytime in case of maintenance. The aim is decreasing time and costs of maintenance, monitoring the building performance, and preventing the damages in case of bad functioning or structural uncertainty
Evaluating Offsite Technologies for Affordable Housing
Availability of an attribute-based evaluation and selection system for offsite technologies is crucial for the adoption of these technologies in mass housing projects. Due to this gap, adoption of offsite technologies remains low in the Indian construction industry in spite of a huge requirement of 18.78 million housing units to be built by 2022. The traditional ‘sticks and bricks’ approach is not likely to fulfil this demand. Adoption of offsite technologies has to be looked into as an option to deliver the extensive requirement in the area of affordable housing. Rejection of technology by evaluating the first cost alone is not the desired strategy to evaluate these offsite technologies. To evaluate and adopt these offsite technologies in affordable housing segment, a holistic selection framework encompassing a set of attributes is needed. This paper identifies a holistic selection framework with a set of offsite specific attributes alongside a set of standard attributes that are mandatory and desired for the adoption of offsite technologies in the affordable housing. Simple scoring of attributes is utilized in devising the framework. This framework is tested and validated on a case study where offsite technologies are used
Recommended from our members
Use of High Fines Concrete (HFC) in Insulated Concrete Form (ICF) Construction
This project work consisted of developing technical data to justify, from the standpoint of material properties (of aggregate fines and HFC), construction efficiency, cost competitiveness, and energy performance, a basis for the use of high-fines concrete (HFC) inside ICF wall systems. Although several aspects of the study are listed above, the report primarily concentrates on the material aspects of a limited number of aggregate fines sources and their use in HFC relative to strength development and placeability. Originally, emphasis was planned to be placed upon the use of a controlled low strength material (CLSM) but due to strength requirements currently in force for ICF construction, it was determined that greater benefit would be derived from highlighting the advantages of using aggregate fines in ICF concrete. A framework for developing suitable HFC mixture designs for different ICF wall systems relative to placement and strength characteristics is discussed. These guidelines were based upon results from the construction to two residential structures using HFC and the placement of 4 trial wall systems. One of the structures consisted of a “test model” that was used to investigate methods of construction and the energy efficiency of an ICF wall system.Aggregates Foundation for Technology, Research, and Education (AFTRE)Civil, Architectural, and Environmental Engineerin
Development of a novel designs and assessment and selection system for green office buildings in China
China is facing severe problems in fossil fuel consumption and pollutant emission largely owing to the construction of buildings. Office buildings, as a major building type in China, contribute around 22% of the national fossil fuel energy use and 14% of carbon emissions. The identification of the most appropriate solution to energy saving and pollutant emissions reducing at the earlier design stage of office buildings is significantly important to China’s sustainability development and environmental protection.This PhD research aims to establish a simple and straight-forward assessment method that can predict fossil fuel energy use and the associated pollutant emissions of the Chinese office buildings at their early conceptual design stage (when the detailed material and constructional information is unavailable), and further, develop a computer- aided assessment and selection process that can identify the best design solution to the office buildings of China. This work is carried out through a standard research process including literature review, methodology development, computer model establishment, case study and results analysis with comparisons, followed by recommendations. As a result, the research provides a variety of important outputs, i.e., the life-cycle energy and air-pollutants estimation method, the generalized environmental impact metric system, and the green office building design solution assessment and selection system (GBAS). It has been demonstrated that the simplified energy and pollutants estimation method can predict the energy consumption and associated pollutant emissions at each office building life-cycle phase, based on the refined mathematical correlations and associated computerized toolkits. By using the generalized environmental impact metric system, the pollutant equivalent (PE), which reflects the combined environmental impact of the emission of four common pollutants, is derived and its values are discussed in detail. Based on the estimation of life-cycle energy and PE, the GBAS system is developed to identify the “best” design solution on both the quantitative survey and qualitative analyses.A combination of all the above outcomes leads to the development of a comprehensive computerized tool that can conduct faster assessment, optimization and selection of the “best” design solutions for Chinese office buildings at their very earlier stage of design. The prediction results have been proven to be rational, realistic and applicable to practical engineering projects.The outcomes of the research can help in the design of energy efficient and “green” office buildings in China, thus contributing to China’s sustainable development and environmental protection
Life-cycle optimization of building performance: a collection of case studies
The building sector is one of the most impacting on the energy demand and on the environment in developed countries, together with industry and transports.
The European Union introduced the topic of nearly zero-energy building (nZEB) and promoted a deep renovations in the existing building stock with the aim of reducing the energy consumption and environmental impacts of the building sector. The design of a nZEB, and in general of a low-energy building, involves different aspects like the economic cost, the comfort indoor, the energy consumption, the life cycle environmental impacts, the different points of view of policy makers, investors and inhabitants. Thus, the adoption of a multicriteria approach is often required in the design process to manage some potential conflicting domains. In detail, one of the most suitable approaches is to integrate the preliminary building design (or renovation) phase in a multi-objective optimization problem, allowing to rapidly compare many alternatives and to identify the most adapt interventions
Integrated seismic and energy retrofitting of existing buildings: A state-of-the-art review
Ageing of the building stock is an issue affecting many regions in the world. This means a large proportion of existing buildings being considered energy inefficient, with associated high energy use for heating and cooling. Through renovation, it is possible to improve their energy-efficiency, hence reducing their significant impact on the total energy household and associated greenhouse gas emissions. In seismic regions, additionally, recent earthquakes have caused significant economic losses, largely due to the vulnerability of older buildings not designed to modern standards. Addressing seismic and energy performance by separate interventions is the common approach currently taken, however to achieve better cost-effectiveness, safety and efficiency, a novel holistic approach to building renovation is an emerging topic in the scientific literature. Proposed solutions range from integrated exoskeleton solutions, over strengthening and insulation solutions for the existing building envelope or their replacement with better materials, to integrated interventions on horizontal elements like roof and floor slabs. To identify pathways to combined seismic and energy retrofitting of buildings, a state-of-the-art review of all materials and solutions investigated to date is presented. This is followed by a critical analysis of their effectiveness, invasiveness, building use disruption as well as their impact on the environment. The assessment of current combined retrofitting research highlights a great potential for their application, with a potential to provide cost-effective renovation solutions for regions with moderate to high seismic risk. Still, to-date there is a lack of experimental research in this field, a need for further work on truly integrated technologies and their validation through applications on existing large-scale buildings. Moreover, there is a need for adequate design methods, regulations and incentives that further the implementation of integrated retrofitting approaches
Retrofit de la construcción mediante paneles prefabricados: una reseña del estado del arte = Building Retrofit through prefabricated panels: an overview on the state of the art
The main aim of this paper is to provide an overview of the use of prefabricated panels in external building retrofitting. Building retrofit represents a pivotal point in terms of energy efficiency, connected to the great amount of existing buildings, both public and private, all around Europe. The need of intervention is underlined by different European Directives, as well as by Horizon 2020 roadmap. Many research works and projects are focusing on the theme of prefabrication in retrofit, stressing the importance of this strategy. The review of the state of the art shows several approaches in terms of prefabricated panels: a critical classification of these projects distinguish between systems based on large and small panels, systems for extensions based on structural panels, and partially prefabricated systems. The classification is useful as it can help in understanding further development of prefabricated panels, underlining the advantages and disadvantages of the systems. The main challenges are linked to design, fabrication, transport and installation. An overview of those issues is also provided, stressing the main innovation fields to be further investigated, and the possible future developments of prefabrication in building retrofit
- …