Whole life costing of domestic energy demand reduction technologies: householder perspectives

A recent, major UK research project investigated technical and social aspects of reducing the CO₂ emissions of UK domestic housing by 50% by the year 2030. As 80% of the UK housing stock that will be present in 2030 has already been built, this study aimed to research the whole life costs of three sets of energy demand reduction technologies for existing housing, over a 25‐year period, suitable to deliver significant CO₂ emissions reduction up to 50%. Demand side technological interventions in the form of fabric upgrades and ventilation systems are identified. Whole life cycle analysis of interventions carried out on two housing variants prominent in the domestic stock under different energy price scenarios is carried out using discounted cash flow and compared with the do‐nothing option. The results show that, despite reducing annual energy bills, there is no clear financial case even over a 25‐year horizon for householders to invest in the proposed interventions that contribute to CO₂ emission reduction targets. When discussed with respect to household income and consumption preferences, the results reveal the need for new policy approaches to overcome the financial and non‐financial hurdles for a mass uptake of energy efficient technologies.     

General framework for bridge life cycle design

Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environmental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes. __________ Translated from Journal of Tongji University (Natural Science), 2007, 35 (8): 1003–1007 [译自: 同济大学学报(自然科学版)]     

Multi-criteria decision-making system for selecting an effective plan for bridge rehabilitation

The managers of the US transportation infrastructure face the challenge of restoring the aging highway infrastructure system and making it perform more reliably, safely and efficiently at minimum cost and with minimum disruption. The process selection of an appropriate construction plan for rehabilitation/reconstruction of a bridge requires its evaluation on the basis of qualitative and quantitative metrics such as construction cost, effect on surrounding businesses and communities and the flow of traffic, etc. Traditional decision-making methods that are focused on costs alone are not equipped to address the multi-objective nature of the decision-making process. This article presents an example demonstrating a decision-making system based on the analytical hierarchy process that can be utilised to transparently extract quantitative weights which reflect the relative importance of both qualitative and quantitative objectives of a project and select a bridge construction plan that best meets the objectives.     

高层建筑与裙房基础整体设计的若干问题

通过带裙房高层建筑与地基基础共同作用的理论研究以及实测调查，就高层建筑与裙房基础整体设计的一些问题提出看法与建议。其中包括整体设计裙房基础悬臂长度的建议值和相对弯曲参考值。推荐在软土地基合适的桩箱（筏）基础沉降计算方法以及上海各类桩持力层基床系数的建议值，以供设计者参考。     

Integrated assessment method for building life cycle environmental and economic performance

Life cycle assessment (LCA) is a powerful tool to identify a building’s environmental impact throughout its life cycle. However, LCA does have limits in practice because it does not consider the economic aspect of project implementation. In order to promote LCA application, a more comprehensive evaluation of building life cycle environmental and economic performance must be performed. To address these issues, we propose life cycle green cost assessment (LCGCA), a method that combines LCA with life cycle costing (LCC). In LCGCA the building’s environmental loads are converted to environmental costs based on the trading price of CO₂ certified emission reductions (CERs). These environmental costs are then included into the building life cycle cost. Subsequently an evaluation index of green net present value (GNPV) for LCGCA can be obtained. A governmental office building in Beijing was studied using LCGCA. Several design options were compared and the sensitivity of the CER price was analyzed. The research also shows that conclusions reached by LCGCA may be different from those of traditional LCC, which does not include environmental costs. The application of LCGCA needs the support of environmental policies. A sound environmental tax mechanism is expected to be established in China soon, which will enable LCGCA to be a useful tool to guide sustainable building design efficiently.     

Lifecycle assessment for sustainable design options of a commercial building in Shanghai

Buildings are long-lasting products which have huge impacts on the environment during their whole lives. The design of buildings should take into consideration long-term environmental and economic benefits. A life cycle assessment approach is developed and demonstrated in a case study—the strategic design of a Flagship Store in Shanghai. Industrial practitioners were invited to the feasibility study. Their opinions were included in the life cycle assessment for the first time. The economic analysis takes account of not only the capital costs of the design options but also the running costs during the building's economic life cycle. The methodology adopted is an integrated life cycle assessment process including life cycle costing, multi-criteria decision making and group decision making methods. The workshops are successful in terms of educational opportunity for the practitioners and have obtained good feedbacks. The top 10 sustainable design options after the life cycle assessment process were chosen by the practitioners as the compulsory design strategies in their global environmental development agenda, whilst the other 32 design options as optional design solution for the international retailer's future stores. The life cycle assessment tool demonstrated by a case study was proven to be a simple and efficient design tool in practice, and therefore it can be adopted in other projects to assist the decision makers.     

Thermal simulation outputs: exploring the concept of patterns in design decision-making

This paper describes the ongoing development of a building performance simulation (BPS) knowledge management scheme for design decision-making. This knowledge management scheme is developed with reference to the patterns of Christopher Alexander and colleagues, which describe commonly recurring abstract problems in architectural design together with successful abstract solutions. As such they form a ‘repository of knowledge’ on architectural design. Patterns have been used in other fields such as software engineering where they also aim at capturing expert knowledge, and their potential to do the same for BPS is explored here. Decision support using simulation is introduced and the concept of patterns described. A pattern structure is developed and some examples given. Interviews with architectural practices investigated whether patterns could support design processes, and the further development of the concept is discussed.     

实现节约型社会的建筑全生命周期设计

在将全生命周期理论与建筑设计方法结合的基础上,阐述了建筑全生命周期的设计理念,从整合设计模式,计算机辅助设计等方面,提出了建筑全生命周期的设计方法,以降低建筑能耗,实现节约型社会。     

Thermal simulation software outputs: a conceptual data model of information presentation for building design decision-making

Building simulation outputs are inherently complex and numerous. Extracting meaningful information from them requires knowledge which mainly resides only in the hands of experts. Initiatives to address this problem tend either to provide very constrained output data interfaces or leave it to the user to customize data organisation and query. This work proposes a conceptual data model from which meaningful dynamic thermal simulation information for building design decision-making may be constructed and presented to the user. It describes how the model was generated and can become operational, with examples of its applications to practical problems. The paper therefore contains useful information for software developers to help in specifying and designing simulation outputs which better respond to building designers’ needs.     

沿海高层建筑抗震设计与耐久性设计的使用年限和性能要求

从沿海高层建筑的抗震与耐久性设计出发,探讨了抗震设计与耐久性设计的设计使用年限、性能要求。设计使用年限的增加意味着地震重现期要延长,对发震断裂带上的建筑地震设防烈度会增大,远离发震断裂带的建筑地震出现的次数增加。耐久性和抗震性危害留的余地不同,耐久性小,抗震性大。但如果耐久性下降会引起抗震性降低。所以保证耐久性是保证抗震性的前提,重视突发性抗震性损坏的同时,不应该忽略长期耐久性损坏的预防。耐久性不足,既增加了结构使用过程中的修理与加固费用,也会降低结构的抗震能力。抗震的性能要求主要体现在保证结构的足够强度、刚度、整体性和稳定性,而耐久性设计要对混凝土材料、结构构造、施工要求等提出要求。     

A review of multi-criteria decision-making methods for infrastructure management

In infrastructure management, multi-criteria decision-making (MCDM) has emerged as a decision support tool to integrate various technical information and stakeholder values. Different MCDM techniques and tools have been developed. This paper presents a comprehensive review on the application of MCDM literature in the field of infrastructure management. Approximately 300 published papers were identified that report MCDM applications in the field of infrastructure management during 1980–2012. The reviewed papers are classified into application to the type of infrastructure (e.g. bridges and pipes), and prevalent decision or intervention (e.g. repair and rehabilitate). In addition, the papers were also classified according to MCDM methods used in the analysis. The paper provides taxonomy of those articles and identifies trends and new developments in MCDM methods. The results suggest that there is a significant growth in MCDM applications in infrastructure management applications of MCDM over the last decade. It has also been noted that many decision support tools based on multiple MCDM methods have been successfully used for infrastructure management.     

The development of life-cycle costing for buildings

The history of the application of life-cycle costing (LCC) began in the UK in the late 1950s and, until now, the state of its development as a concept is not clear. A literature review is presented that shows the changing approaches to LCC by drawing on four major academic journals and 45 peer-reviewed papers. The review verifies that there is a revival of interest in using LCC in tandem with other life-cycle methodologies for research on sustainable building. It also presents a set of methods that are applicable to model and estimate the life-cycle costs of ‘conventional’ and ‘green’ buildings with the objective of distinguishing them. Through the information gathered, it provides a centralized source of reference for the assumptions used in LCC calculations concerning some key input parameters. The finding shows an increasing trend of publications on the evaluation of economic options for green building designs and performance. The directions are clear that the concepts and methods have to evolve to a state where they will help to integrate and optimize economic, social and environmental considerations to deliver more sustainable built environments in the future.     

A life cycle costing approach for discounting in age and interval replacement optimisation models for civil infrastructure assets

Civil infrastructure assets, such as roads, locks, bridges, treatment plants and storm surge barriers, are often characterised by long service lives and corresponding technical life cycles. When life cycles are long, the time value of money plays a role in asset management decision-making on capital investments and operation and maintenance expenditures. In this paper, a new life cycle costing (LCC) approach for discounting in two classes of maintenance optimisation models is developed. These models are the age replacement model and the interval replacement model. Three well-known LCC techniques, which are the present worth, the capital recovery and the capitalised equivalent worth, are combined and used to develop a stepwise methodology. This methodology is validated with the few case-specific mathematical equations that exist in the literature. The advantage of using this alternative LCC approach is its applicability and flexibility for reliability and maintenance engineers. The resulting LCC method builds on well-known LCC formula and enhances the understanding of the inclusion of discounting principles in reliability models. Understanding these principles makes the method flexible. Practitioners can extend or adapt the method to changing circumstances, such as additional cash flows and altering reliability modelling.     

论建设项目全寿命周期管理成本控制

阐述了建设项目全寿命周期的概念,对建设项目全寿命周期各阶段的管理内容进行了分析,从业主的角度探讨了建设项目全寿命周期管理成本控制的几项措施,从而有效降低建设项目全寿命周期成本。     

Systemic life cycle design error reduction model for construction and engineering projects

Design errors have resulted in a plethora of catastrophic building and engineering failures, and some cases have caused death and injury to workers and members of the public. Despite continued efforts to improve project performance, errors remain a significant problem due to recurrent error- traps that prevail at the people, organisational and project levels. In addressing the need to reduce error, a systemic model that is grounded in practice and the aggregated views of 46 practitioners who were interviewed about the nature and prevention of design errors is proposed. The developed model can be used to identify and mitigate design errors as well as stimulate learning throughout a project's life cycle.     

结构方案设计模糊多属性决策的模糊贴近度方法

结构方案设计具有典型的“软科学”决策特点,需要运用“软设计”理论和“软计算”方法进行此类问题的求解。结构方案设计的问题求解过程包括方案生成、方案评价和方案决策三个子过程。其中,结构方案的决策属于典型的多属性决策问题,决策过程中需要运用决策者的偏好信息和方案属性的不确定性信息,因此,采用传统的多准则决策理论不能对此问题进行有效的求解。为此,本文建立了结构方案设计的模糊多属性决策模型,给出了属性模糊满意度矩阵的确定方法,以有效地处理模糊信息。为了克服直接采用欧式距离确定偏好最优方案的缺点,提出了一个基于模糊贴近度的模糊多属性决策方法,并给出了具体的求解程序。以某大跨空间结构方案设计为例,说明了结构设计方案优选的决策过程。实例应用的结果表明,本文提出的方法可以有效地处理不确定性环境下结构方案的优选决策问题。     

建设项目全寿命周期成本控制探析

一个建设项目,如何对项目前期决策至竣工的全过程进行有效地决策、控制和协调,在计划的投资范围内和预定的建设期限内,顺利完成建设任务并达到所要求的工程质量标准,创造尽可能大的有形和无形效益,已成为当前建筑行业迫切需要研究的重要课题。文章旨在通过分析建设项目全寿命周期下的成本控制,探讨各要素成本之间的相互关系,采用相应的措施,实现建设项目整个寿命周期成本最优化。     

Thermal simulation software outputs: a framework to produce meaningful information for design decision-making

This paper describes a process used to develop and test a framework to produce thermal simulation post-processed information meaningful to building design decision-making. The framework adopts a user-centred approach in which the building designer is considered the ultimate simulation tool user either directly or indirectly when supported by consultants. The framework supports the building designer's ‘modus operandi’ and is developed through a set of interdisciplinary research methods. Participatory Action Research, Thematic Analysis and Grounded Theory are used, together with principles from Information Visualization, dynamic thermal modelling and Building Design, following a design approach to problem-solving taken from the discipline of Interaction Design. The various elements of the framework and their connections are derived from analysis of sequences of design actions made by novice designers undertaking complex design activities. Tests of the framework are undertaken through an online questionnaire and five semi-structured interviews with UK architectural design practices.     

全生命周期节能标准厂房设计策略

根据建筑全生命周期设计理念，将其节能设计准则与标准厂房规划设计进行整合，从功能适用性、技术先进性、环境协调性上提出了设计方法和策略。