Housing refurbishment contractors selection based on a hybrid fuzzy-QFD approach

With low demand for new construction, limited land usage, and being aware of sustainability, the refurbishment market has grown greatly and has become more in demand in the construction industry. Most refurbishment work, however, involves a high level of risk, uncertainty, and coordination, which are likely to cause asymmetric information between contractors and residents in a refurbishment process. Most private refurbishment contractor selections are usually based on word-of-mouth referrals that lack a systematic and objective assessment method. This study proposes a hybrid approach combining fuzzy set theory and quality function deployment (QFD) to establish a housing refurbishment contractor selection model. With this model, residents can select an optimal refurbishment contractor according to requirements. To test the effectiveness of the proposed model, a known multiple criteria decision-making method, PROMETHEE, is applied to compare the results of contractor selections. The result reveals that the proposed hybrid fuzzy-QFD approach can be expected to be successful and has potential for handling multiple criteria decision-making problems.     

多媒体技术在建筑设计方案演示中的运用

传统方案讲解演示的过程基本上由设计者和讲解内容二要素构成。过去的建筑设计方案讲解就是这样一种典型的传统方式。但随着建筑设计内容的复杂化和现代信息技术的迅速发展,建筑设计方案演示过程中引进多媒体技术已刻不容缓。通过一个实例,探讨了多媒体技术在建筑设计方案演示中的运用。     

Refurbishment management practices in the shipping and construction industries — lessons to be learned

The management of refurbishment work in both sectors is complex, highly specialized and contains elements of works which are unique to refurbishment and which are different from new work. Ship refurbishment clients are better informed and more knowledgeable about refurbishment processes and products than construction clients and are more involved in the planning and decision making process. The authors claim that there is very little evidence of formal or structured processes of managing risks and uncertainty in refurbishment, in both sectors, especially the quantification and evaluation of risks. There is also an urgent need for educators and refurbishment organizations to address the issue of under-provision of refurbishment management courses.     

Multivariant design and multiple criteria analysis of building refurbishments

In order to design and realize an efficient building refurbishment, it is necessary to carry out an exhaustive investigation of all solutions that form it. The efficiency level of the considered building's refurbishment depends on a great many of factors, including: cost of refurbishment, annual fuel economy after refurbishment, tentative pay-back time, harmfulness to health of the materials used, aesthetics, maintenance properties, functionality, comfort, sound insulation and longevity, etc. Solutions of an alternative character allow for a more rational and realistic assessment of economic, ecological, legislative, climatic, social and political conditions, traditions and for better the satisfaction of customer requirements. They also enable one to cut down on refurbishment costs. In carrying out the multivariant design and multiple criteria analysis of a building refurbishment much data was processed and evaluated. Feasible alternatives could be as many as 100,000. How to perform a multivariant design and multiple criteria analysis of alternate alternatives based on the enormous amount of information became the problem. Method of multivariant design and multiple criteria of a building refurbishment's analysis were developed by the authors to solve the above problems. In order to demonstrate the developed method, a practical example is presented in this paper.     

A new clustering and visualization method to evaluate urban heat energy planning scenarios

Spatial visualization is a very useful tool to help decision-makers in the urban planning process, i) to define future energy transition pathways, ii) to implement energy efficiency strategies and iii) to integrate renewable energy technologies in the context of sustainable cities. There is thus a need to develop new tools to understand the energy consumption patterns across cities. Statistical methods are often used to understand the driving parameters of energy consumption but rarely used to evaluate future urban refurbishment scenarios. Simulating whole cities using energy demand softwares can be very extensive in terms of computer resources and data collection. A new methodology, using city archetypes, is hence proposed to simulate the energy consumption of urban areas and to evaluate urban energy planning scenarios. The objective of this paper is to present a solid framework and innovative solution for the computation and visualization of energy saving at the city scale. The energy demand of cities, as well as the microclimatic conditions, are calculated by using a 3D model designed as function of the real city urban geometrical and physical characteristics. Data are extracted from a GIS database. We demonstrate how the number of buildings to be simulated can be drastically reduced thereby significantly decreasing the computational time and without compromising the accuracy of the results. This model is then used to evaluate the influence of two sets of refurbishment solutions. The energy consumption are then integrated back in the GIS to identify the areas in the city where refurbishment works are needed more rapidly. The city of Settimo Torinese (Italy) is used as a demonstrator for the proposed methodology, which can be applied to medium-sized cities worldwide with limited amount of information.     

Drivers and benefits for district-scale energy refurbishment

Existing building stock is responsible for a significant share of energy consumption in cities, consequent emissions, and effects on climate change. Energy refurbishment of buildings can have an essential contribution to sustainable strategies of cities in Europe. District-Scale Refurbishment (D-SR) has many benefits compared to single building refurbishment, but some barriers have delayed the realisation of district-scale projects. This article aims to explain the importance of district-scale approaches for energy-efficient refurbishment and presents the findings related to the need for a new-type of role needed to accelerate district-level energy-efficient refurbishment projects, defined as an “activator”. Threefold methodology was applied to conduct this study including (1) a literature review to analyse issues that enable or hinder district-scale energy refurbishment of existing buildings, (2) twenty-five semi-structured interviews were carried out of pioneering representatives of architectural engineering and construction (AEC) in Finland and the questionnaire was designed to encompass Osterwalder's business canvas approach. Thematic findings were identified based on the qualitative results of the interviews.The results of this study demonstrate that while district-scale refurbishment is seen beneficial in many aspects, it requires new roles, and an activator is needed to initiate and possibly lead the process. At the same time, the role of the municipality emerged as extremely important as an enabler by supporting flexible town-planning, open information, strong support for citizens' participation processes and by providing incentives for starting the process. The optimum profile of an activator is very demanding, requiring skills in process understanding, networking, and collaboration, in addition to expertise in energy solutions and technologies. This role could be taken by, e.g. contractors, project managers or engineering companies. The major challenge remains concerning who would pay for the role of an ‘activator’ during the initial stages of D-SR. This could be solved e.g. through a national incentive or the activator could be hired by the municipality. The value proposition should be for the end-users and could be based on (a) saving or increasing the value of a residential flat, (b) improving the living environment and increasing the attractiveness of the district, (c) improving well-being, or (d) easiness of refurbishment process.     

Planning with Hypermedia Combining Text,Graphics, Sound,and Video

One of the most exciting areas of development in computer technology today is the organization and display of information using a variety of media. Commonly termed “hypermedia,” this technology allows one to combine text with interactive video, maps, animation, graphics, and sound. In this report we examine the terminology and history of the development of hypermedia, evaluate three current software packages (Hyper-card, Supercard, and Guide), and describe three hypermedia applications relevant to planning practice. We conclude that there will be an explosion of planning information available in digital form, and that hypermedia technology will help us organize this information, and will form the basis for much more powerful decision support systems for planning.     

GA-based decision support system for housing condition assessment and refurbishment strategies

Refurbishment work involves improvement, upgrading, renovation, retrofit, and repair of existing housing. With limited land usage and being aware of sustainability, the refurbishment market has faced increasing needs worldwide. During the long life cycle period of housing, most residents are undoubtedly faced with refurbishment requirements. However, it is not easy to make assessment and refurbishment related decisions due to the lack of knowledge and experience. This study presents Genetic algorithm-based on-line decision support system (DSS) to help residents easily conduct the housing condition assessment and offers optimal refurbishment actions considering the trade-off between cost and quality. Two refurbishment models are developed to explore the relationship among the life cycle cost, restoration cost and improved quality. The result reveals the proposed DSS solves the problems arising from asymmetric information and conflicting interests between residents and contractors, as well as improves traditional housing condition assessment to be more effective and efficient.     

Energetische Sanierung von Schulgebäuden in den neuen Bundesländern – Sanierungsprojekt Förderschule Rathenow

Energy efficiency improvements for school buildings in Germany's new federal states; Rathenow special school refurbishment project. Current energy saving measures for existing buildings focus on refurbishment of schools and other educational buildings. The building described in this article represents the standard type of a large‐panel construction series in the new federal states. Due to the large number of buildings (540) constructed in this way the project can act as a model for similar projects. Initial studies indicated that structural refurbishment measures for these buildings are required as a matter or urgency. The energy performance calculations for the building showed good agreement between the calculated demand values and actual heating energy consumption values and can serve as basis for predictions of energy savings through various refurbishment measures. The new DIN 18599 calculation standard enables significantly more differentiated consideration of boundary conditions such as occupied periods, occupancy levels, internal heat sources, and the effect of night setback. Based on comparative calculations, different refurbishment concepts can be developed and assessed.     

Cost modelling in underpinning projects

Large refurbishment projects are characterized by highly varied costs from one project to another. In Finnish underpinning, only retrospective analysis of costs has been available for the owner’s decision process. In order to develop tools for pre‐tender cost estimating and for comparison of different design solutions and evaluation of tenders of the underpinning project, two different cost models have been developed for research. In both models developed, the minimum data required is the pile length. In the more detailed model, the assessment is based on the design solution, including known pile types and the load transfer classification. Both models are easy to use, and the percentage of explained variance is fairly good in the more detailed model.     

Historic Building Information Modelling: performance assessment for diagnosis-aided information modelling and management

Building Information Modelling, new paradigm of digital design and management, shows great potential for the refurbishment process, as it represents a possible way out of criticalities that occur in documentation and preservation of existing assets, if connected to cognitive automation. The combination of BIM with automation systems improves the quality control during diagnosis, design and work execution, and the labour savings, which is particularly relevant for rapid intervention in case of hazardous conditions.Therefore, the paper is going to address a methodological discussion concerning complete “as-built” parametric models of historical buildings, supporting the design of refurbishment and conservation interventions. Although some reviews of the state of the art exist on the topic of Historic Building Information Modelling, the present research introduces a different perspective on HBIM modelling, with diagnosis and performance assessment as key-aspects, in terms of automating performance assessment.Specifically, from the data collection of contributions regarding HBIM/BIM, diagnostics and monitoring on existing buildings and infrastructures, a critical review by selected criteria is developed. Nevertheless, general methods and tools for information management and exchange tasks in BIM are briefly described as well, since they are considered useful for future developments of HBIM approach. The core of the critical analysis is focused on the scientific and technical relations among HBIM models, diagnosis and performance assessment features. In addition, the review identifies specific activities and relative tools and methods for knowledge acquisition and semantic enrichment.Finally, gaps in knowledge of the current literature are outlined and discussed, with specific focus on performance assessment in HBIM. In this regard, a new methodology toward Diagnosis-Aided Historic Building Information Modelling and Management (DA-HBIMM) is proposed as a framework to be developed in order to address smart knowledge acquisition, collection and notification of assessed performances and eventual risks, by cognitive automation and artificial intelligence, in the near future.     

An optimisation process to motivate effective adoption of BIM for refurbishment of complex buildings in New Zealand

Despite the multidisciplinary networks involved in refurbishment of complex building projects, the lack of BIM adoption signifies lack of real BIM benefits towards acceptance of BIM within Architecture, Engineering and Construction (AEC).To this end, this study empirically examines the potential real benefits between traditional network and BIM network for a real-time refurbishment case study project, through agent-based simulation modelling. A social network analysis theory is adapted to model the project interaction networks and a BIM prototype network. An assessment of the main stakeholders for BIM perception is carried out. We offered three prototype interaction networks for comparison of real BIM benefit.An agent-based Bayesian network model is used to simulate the propagation of design error within the project networks. The result of the analysis show that BIM project diffuses error efficiently, while stakeholders recovers faster and nearly at the same time than traditional network. The optimised network shows better performance to the traditional network, when there is early involvement of subcontractors. The main contribution of this study is providing a novel approach to compare real benefits for traditional method to BIM method for refurbishment project and to provide avenue for project stakeholders to optimise their interaction through adoption of BIM.     

Periodic refurbishment and reductions in national costs to sustain dwelling services

This paper uses a simulation model to make exploratory estimates of current and potential reductions in national costs to sustain dwelling services due to refurbishment. Data and parameters are based on a typical New Zealand dwelling of lightweight timber framed construction. Dwelling service years provided by a dwelling over one year adjusted for depreciation serve as a proxy for benefits. The costs to construct one dwelling and fractions thereof serve as a proxy for the costs of maintenance, refurbishment, replacement, and new construction. Current levels of refurbishment reduce national average costs to sustain dwelling services by a magnitude of 15%. Potential reductions in national costs are modest (5%) should the housing stock be stationary, but are negligible when the expansion rate of the housing stock is as high as 2.0% per year. A decline in the expansion rate of a housing stock has a greater impact on reducing national costs than an increase in the number of cycles of refurbishment.     

Service management in housing refurbishment: a theoretical approach

It is unusual to find that housing refurbishment projects have been undertaken with a clear focus on customer orientation directed towards the tenants, or owners of cooperative flats or condominiums. Only recently have researchers in construction management begun to look closer at the relationship between contractors and customers. To assess the scope for customer orientation in the refurbishment industry, current thinking in service management is reviewed here in an attempt to identify principles with implications for housing refurbishment. There is a consensus among service management investigators that services are intangible; other often mentioned characteristics are heterogeneity, perishability, and the inseparability of production and consumption. Except for inseparability these characteristics are valid for refurbishment. Nevertheless, features such as the long turn-round time, the number of participants, the complexity and the uncertainty, distinguish housing refurbishment from most services. There is strong empirical support for the claim that customer satisfaction increases customer loyalty and gives the service producer a positive reputation, ultimately increasing profitability. It is concluded that this insight can be interpreted operationally for housing refurbishment projects, bearing in mind that the tenant or the owner of a cooperative flat is the customer's customer.     

A comprehensive model for streamlining low-energy building design

Building designers are often limited in their ability to reduce the environmental impact of buildings, due to a lack of information on the environmental performance of building components as well as inconsistencies in the way in which this information is derived. Whilst numerous tools exist to help facilitate the low-energy building design process, these typically require large investments of time and money that are often beyond those available within any particular project. This paper describes an approach for streamlining the design process to reduce building life cycle energy consumption. Building assemblies are ranked based on an assessment of the life cycle energy requirements associated with their use within a building. This facilitates early stage assessment, negating the need for a resolved design before the relative energy requirements of alternate design solutions are known. Previous work assessed the initial and recurring embodied energy as well as the operational energy requirements for heating and cooling associated with the use of a range of building assemblies, using a simplified house model. This paper presents a sensitivity analysis of variations to the floor area, shape and orientation of this model, to test the reliability and applicability of the ranking approach across a broad range of circumstances. It was found that these variations did not influence the ranked order of the assemblies in terms of their life cycle energy requirements. Thus, the ranking of assemblies appears to provide an appropriate approach for streamlining the selection of construction elements during the building design process.     

曼彻斯特城市更生--曼城旧建筑的改造与再利用

本文通过介绍英国及曼城的建筑历史，阐释建筑风格和材料对旧建筑改扩建的影响，并结合设计实例，试图从建筑空间的再利用，改扩建，建筑自身新旧部分的关系和材料的运用几个方面展开说明，阐述曼特城市更生策略。     

保温系统

当涉及到新建筑或者旧建筑的整修时,需要不同形状、不同功能以及不同尺寸的门窗系统。关键是元件要有尽可能高的保温性能。     

基于风景园林信息模型(LIM)的山地 景观地形参数化设计实验研究——以 Civil 3D和InfraWorks交互设计为例

缺乏参数关联与控制的山地设计在科学性与精准性 上出现诸多设计障碍,如山地场地、道路等三维设计信息与二 维设计不匹配;山地曲线、曲面地形要素设计精度不高等。 借鉴BIM技术在建筑参数化设计中的应用,探索Civil 3D与 InfraWorks协同处理山地地形并进行信息交互的设计方法, 完成山地地形三维模型设计与二维设计的参数关联,从而优化 山地设计程序,提高山地设计精细化程度,并为设计者即时提 供设计反馈信息和设计变更途径。通过研究实现山地景观信息 在BIM平台中的集成应用,构建基于风景园林信息模型(LIM) 的山地设计路径,为山地地形设计提供参数化解决方案。     

偏心加载钢筋混凝土结构破坏过程的数值模拟

用材料破坏过程分析系统MFPA2D(material failure process analysis)数值模拟方法对钢筋混凝土桥墩在偏心加载条件下的受力、变形与内部裂缝萌生、扩展及最终破坏的全过程进行了数值模拟.数值模型中引入了统计分布函数,反映了混凝土的非均匀性影响,并采用具有残余强度的弹脆性本构模型及破坏单元材料性质退化方法,利用偏心加载方式对钢筋混凝土构件实施加载.数值试验得出的荷载-位移曲线及破坏模式图与文献的试验结果较接近,数值试验还给出了试件破坏过程图及应力分布图,再现了整个破坏过程,而且通过对模型中受拉区2个多单元信息剖线的提取,对剖线中不同位置点应力随加载步的变化情况进行了研究和分析,揭示了结构破坏的机理.数值试验结果对于深入了解钢筋和混凝土的联合受力规律有参考价值.     

代际互助模式下东北寒地城市住宅改造研究

在严酷的气候背景及社会发展背景下,东北寒地城市具有大量既有住宅亟待改造,全面的改造不仅仅是建筑节能性能的提高,也包含居住模式变化对建筑空间环境产生的改造要求。近年来,我国应对老龄化趋势在人口政策方面做出了大幅度调整,通过解析东北寒地城市既有住宅的本质特征及适老化需求特点,分析其改造关键问题,以积极老龄化理念为指引,发掘"代际互助模式"在该地区住宅改造中应用的可行性,建构基于此模式的东北寒地城市既有住宅改造研究平台。