The future of building economics: a note

Building economics has been long in emerging because it still lacks solid theoretical foundations. The notion of ‘building process’ should play a central role in this regard, as it points at the fundamental indeterminacy underlying building activity from conception to demolition. This indeterminacy stems from the length of time that usually separates these two events. Building economics needs to shift its focus from investment decisions to problems of managing building portfolios in their entirety. The professional basis for this development is in corporate real estate and facilities management.     

The life cycle costing (LCC) approach: a conceptual discussion of its usefulness for environmental decision-making

Ten LCC-oriented environmental accounting tools suggested as useful in environmental decision-making have been identified. However, their implementation in the building industry seems to be limited, which opens up for a conceptual discussion. The purpose of this article is to discuss theoretical assumptions and the practical usefulness of the LCC approach in making environmentally responsible investment decisions. LCC's monetary unit and extended scope may speak in favour of using LCC but LCC fails to handle irreversible decisions, neglects items that have no owner and does not consider costs to future generations. Moreover, LCC does not take into account the decision makers’ limited ability to make rational decisions under uncertainty. LCC's practical usefulness is constrained by its oversimplification to a monetary unit, the lack of reliable data, complexity of the building process and conceptual confusions. To handle these inconsistencies in future development of environmental decision support tools three research solutions are proposed.     

Towards an explicit design decision process: the case of the structural frame

Decisions made during the briefing and conceptual design stages of a building project are critical to its success. One of the earliest major decisions which can have a significant effect on downstream events and results is the selection of the structural frame. Given its importance to the efficacy of the finished building, the structural frame selection process should arguably be objective and transparent, the final decision being based on the frame's ability to perform against a range of criteria appropriate to the scheme in question. However, the heuristics underpinning such decisions tend not to be explicit and thus, are difficult for inexperienced clients to understand. This article reports on research which examined the criteria used by clients, structural engineers, architects and main contractors when selecting structural frames. These were established via a postal questionnaire survey of a stratified sample of design professionals, contractors and client organizations. The analysis reveals marked differences in the perceived importance of the criteria identified amongst the respondents, which may result in conflicts between design and construction advisers and their clients should they be made explicit in the design process. Nevertheless, it is important that such differences are revealed within the decision‐making process if more appropriate design decisions are to be made in the future.     

Architects need environmental feedback

The role of environmental feedback within architects' offices is examined as a fundamental ingredient of sustainability. Three case study buildings are examined using a feedback exercise encompassing the whole building process from early key design decisions to occupation. Results show that sometimes design decisions are taken for aesthetic reasons without certainty on their environmental impact. Improvements are possible especially in energy consumption, glare, the usability of controls, the communication of strategies and comfort conditions. The architects report the feedback lessons relevant for their work. A systematic approach to project feedback is proposed with emphasis in feeding forward to new projects and recording decision-making. To close the information loop, briefs need explicitly to mention performance targets for energy use, management expectations, control requirements and to promote feedback itself.     

监理人员绩效考核的信度与效度分析

监理企业作为一种有偿性技术服务行业,其向市场提供服务的价值载体——监理人员对监理项目的成败及企业口碑、品牌的打造都有着重要的意义。建立一套完善的监理人员绩效考核体系,并有效地贯彻执行该体系已成为很多监理企业的迫切诉求。基于对监理人员进行绩效考核的重要性和考核过程中大量不确定因素的存在,对监理人员绩效考核的信度和效度验证分析方法进行了研究,提出了离散程度分析和评价主体一致、有效性分析的信度检验方法,以及兼顾绩效考核内容与结构两方面的效度分析方法。该研究成果因其简单、实用且可操作性强的特点,将对监理企业的人事管理工作具有很强的指导意义。     

项目投资决策评价模型及其应用

旨在通过构建投资机会评价模型及相关评价指标 ,以系统分析的观点科学、客观的对投资机会进行择优评价 ,以达到避免盲目投资 ,保障国民经济健康发展和确保投资主体利益的目的     

财政投资工程项目评审面临的问题及对策分析

在深入分析当前财政投资评审工作中面临问题的基础上,提出了若干对策性建议,力求为今后一段时间的财政投资评审工作的顺利进行提供一些参考意见,从而充分发挥财政投资评审在财政基本建设支出预算管理中的监督作用,确保财政投资资金的使用效果。     

An assessment technique for the evaluation and promotion of sustainable Olympic design and urban development

A response is presented to the dilemma of hosting resource-intensive large-scale sporting events at a time when requirements for sustainability and sustainable development must also be met. A framework was devised for judging development and design issues for future planning, one which is based upon extant historic evidence from host city experiences as well as previous event outcomes. It offers potential to compare plans against best/optimal practice. The technique for appraisal arises from a detailed analysis of Olympic Games held since 1896. Data associated with venue design, construction and usage, athletes' accommodation, and the facilities for officials, the media and visitors/spectators, were amassed and reviewed. An evaluation technique was produced which demonstrates how the organizers of a modern Olympic Games can assess and reflect upon planning, design and development decisions associated with their own city from an early outline stage. This should permit less wasteful, more appropriate and more sustainable Games' infrastructures to be considered before complex detailed development occurs.     

关于企业投资决策的探讨

随着社会经济的不断发展,企业投资的不定因素也随之增多,为了保证企业投资的效益最大化,企业领导者就要充分分析投资决策影响因素,从而实现科学的企业投资决策,使企业健康快速的发展。     

The Management and Creation of Beaches for Coastal Defence

The creation and management of beaches using natural mobile materials can often provide a cost-effective and environmentally appropriate coastal defence. This paper summarizes recent practical endeavours in beach creation and management. Reference is made to the natural sources of beach building materials and to the numerical and physical models that may be employed to assist in the definition both of material transport paths and their magnitude. Risk analysis is noted to be a necessary part of the beach design process together with an appraisal of the coastal hydrodynamics and topographical constraints of the site of interest. The techniques that have been employed to recycle beach materials on some frontages are described, with comments on bypassing materials around obstructions. The paper describes the important considerations to be made when material is being imported to a beach, and notes some of the presently used techniques. Important points are drawn out for the future of beach creation and management, and a number of research needs and administrative difficulties are highlighted.     

Integrating physical and virtual environments to conserve energy in buildings

Fundamental understandings of how energy is consumed, monitored, and controlled are key prerequisites for an energy conservation process. Users who know exactly when energy consumption occurs and where it takes place are able to make more informed decisions about how to lower their energy consumption. Energy conservation projects in the U.S. have reported a 2-11% savings when users are presented with information on energy consumption. Engineers are increasingly turning to virtual environments to improve system design and development and optimize performance and increase efficiency during operation. A bottom-up approach to real-time energy monitoring by integrating virtual and physical domains to increase user awareness on where, when, how and why aspect of energy to make inform decisions regarding energy consumption, optimization and conservation is proposed. A virtual 3-D environment is developed to display actual space/zone/building real-time power consumption information and to allow users to easily locate equipment/loads that are in standby/inefficient and causing energy waste in the real/physical environment. The proposed system is demonstrated via a prototype board that is virtually integrated with an actual Zero Net Energy Test House (ZNETH) as part of future Net-Zero Energy buildings research. The results establish a promising tool in this filed.     

Environmental impact analysis for typical office facades

The design of a building facade influences internal thermal and lighting conditions and energy use associated with the provision of these conditions. Key decisions about the building facade are usually taken during the concept design stage of a building, while decisions about the method of providing the environmental conditions are often made later in the design process. This dilemma is addressed by the development of a concept design tool that allows the design team to investigate the effect of facade design on the resulting internal environmental conditions, energy use and environmental impact. The concept design tool was developed by performing detailed thermal, lighting and environmental modelling for a number of generic office building facade designs and a range of parameters that affect directly the environmental performance of an office building. The results are presented in a user-friendly interface requiring a minimum number of inputs. Key parameter outputs (such as temperature, lighting levels, heating/cooling energy demand, embodied energy and eco-points) can then be viewed, while a more detailed analysis can also be created for specified facade designs. A parametric analysis of the summary result outputs for selected facade parameters indicates that natural ventilation and cooling can reduce the environmental impact of offices by up to 16%, although heating energy demand could increase significantly. Improving the construction standard of the facade and reducing the internal heat loads can reduce the environmental impact by up to 22%. Use of this tool at early design stages will benefit the design team through an improved understanding of the dynamics between facade design and building services and assist with a more integrated approach.     

Service life planning and performance requirements

Service life planning comprises a model for the determination of a reasonable expected service life for buildings and components, and it establishes a routine for the assessment of design alternatives. A design option is considered reasonable when it meets or exceeds performance requirements over time that have been drawn up specifically for the specific project. Due to this assessment reference, there is a very evident link to the concept of performance-based building. Any stakeholder involved in the value chain or in the design process of the building, as well as regulators and building users, can express performance requirements. Identified requirements, both in relevance and in quality, will vary with the stakeholder and his/her perspective of interest. As building sector manufacturers develop most products with reference to standards rather than with reference to specific requirements, there is no direct link from user requirements to the product design. Instead, the building designer has the responsibility to ensure performance requirements are met by the performance of products integrated into the design. As these design decisions also have to be made at the material and component level, a performance-based building would benefit from an established rationale that enables the communication of performance requirements across the relevant system levels in the relevant design processes. A path for the connection of the established concepts of service life planning and performance-based building is presented. The aim is to identify key elements that need to be developed for the successful linkage of performance-based building with service life planning.     

A stochastic programming approach to enhance the resilience of infrastructure under weather-related risk

The presented methodology results in an optimal portfolio of resilience-oriented resource allocation under weather-related risks. The pre-event mitigations improve the capacity of the transportation system to absorb shocks from future natural hazards, contributing to risk reduction. The post-event recovery planning results in enhancing the system's ability to bounce back rapidly, promoting network resilience. Considering the complex nature of the problem due to uncertainty of hazards, and the impact of the pre-event decisions on post-event planning, this study formulates a nonlinear two-stage stochastic programming (NTSSP) model, with the objective of minimizing the direct construction investment and indirect costs in both pre-event mitigation and post-event recovery stages. In the model, the first stage prioritizes a bridge group that will be retrofitted or repaired to improve the system's robustness and redundancy. The second stage elaborates the uncertain occurrence of a type of natural hazard with any potential intensity at any possible network location. The damaged state of the network is dependent on decisions made on first-stage mitigation efforts. While there has been research addressing the optimization of pre-event or post-event efforts, the number of studies addressing two stages in the same framework is limited. Even such studies are limited in their application due to the consideration of small networks with a limited number of assets. The NTSSP model addresses this gap and builds a large-scale data-driven simulation environment. To effectively solve the NTSSP model, a hybrid heuristic method of evolution strategy with high-performance parallel computing is applied, through which the evolutionary process is accelerated, and the computing time is reduced as a result. The NTSSP model is implemented in a test-bed transportation network in Iowa under flood hazards. The results show that the NTSSP model balances the economy and efficiency on risk mitigation within the budgetary investment while constantly providing a resilient system during the full two-stage course.     

基于实物期权的既有建筑节能改造投资策略分析

针对能源价格波动服从均值回归过程的特征,构建实物期权模型研究既有建筑节能改造的最优投资策略。采用数值方法定量分析节能改造项目的实物期权价值和最优投资阈值,并结合上海某住宅小区的节能改造案例探讨不确定参数的变化对投资阈值的影响。研究发现:当投资阈值高于能源价格时,投资主体会选择等待来降低风险;在能源价格波动率大、投资成本高或者无风险利率比较高时,投资主体会选择等待观望,规避风险。     

智能建筑中的综合布线

土木建筑百年大计,一次性投资很大。在当前国力尚不富裕的情况下,全面实现建筑智能化是有难度的,然而又不能等到资金全部到位,再去开工建设,因为这样会失去时间和机遇。对于每个高层建筑,一旦条件成熟需要改造升级为智能建筑,也是不容置疑的。这些可能是目前高层建筑普遍存在的一个突出矛盾。综合布线是解决将当前和未来统一这一矛盾的最佳途径。综合布线只是智能建筑的一部分。它犹如智能建筑内的一条高速公路,可以统一规划、统一设计,在建筑物建设阶段投资占整个建筑物资金的3%～5%,将连接线缆综合布线在建筑物内。至于楼内安装或增设什么应用系统,这就完全可以根据时间和需要、发展与可能来决定。只要有了综合布线这条信息高速公路,想跑什么＂车＂,想上什么应用系统,就变得非常简单了。尤其目前兴建的高大楼群如何与时代同步,如何能适应科技发展的需要,又不增加过多的投资,综合布线平台是最佳选择。否则,不仅为高层建筑将来的发展带来很多后遗症,并且一旦打算向智能建筑靠拢时,要花费更多的投资,这是十分不合理的。     

Systems-of-systems methodology for strategic infrastructure decision making: Ireland as a case study

Infrastructure development is a long term process, which cannot easily adapt to sudden change; and infrastructure assets can have long lifetimes. Poor investment choices risk locking in poor policy choices for substantial periods of time. The ‘need’ for a new infrastructure asset arises due to demographic, economic or policy changes. But historically Ireland’s infrastructure investment has also been driven, in part, by the pursuit of political / economic policies which have themselves ‘created’ infrastructure needs; and often decided on an isolated project-by-project basis. In contrast, a systems-of-systems (SoS) approach is a fusion of network modelling, consideration of various policy options, and appraisal of the impact of alternative demographic and economic scenarios on multiple systems. This paper assesses Ireland’s readiness to adopt a SoS approach to infrastructure decision-making, proposes a methodology for its development and implementation. This would enable the demand for new infrastructure to be tested under various policy scenarios, providing evidence for investment decisions.     

火灾后混凝土结构检测鉴定与加固设计

建筑火灾的发生直接危害人类的生命财产,同时对建筑结构本身产生不利影响。钢筋混凝土结构在遭受火灾后,结构材料性能发生变化,受损构件的承载力、变形、耐久性、抗震性能受到不同程度的削弱,混凝土结构的可靠性大大降低。因此,火灾后混凝土结构检测鉴定和加固设计成为亟待解决的实际问题。文章结合工程实例,介绍火灾后现场调查、检测鉴定以及加固设计,为日后实际工程提供参考。     

某综合楼火灾后的检测鉴定

文章介绍了某综合楼火灾后的调查情况,经过初步鉴定、详细鉴定两个阶段,阐述了该房屋火灾后的检测鉴定过程,推断出火场温度分布情况,并对受损构件作鉴定评级,提出了处理建议,为加固设计提供参考依据。     

Translating Singapore architects' environmental awareness into decision making

Construction activity is known to have a major impact on the environment. Construction is a major consumer of a wide range of naturally occurring and synthesized resources. The extraction, processing and utilization of these resources can have various negative impacts on the environment. With increased awareness and knowledge of these impacts, efforts are being made to avoid these adverse effects. Among these is the selection and specification of appropriate materials. This paper studies the level of environmental awareness and knowledge of architects in Singapore when selecting and specifying materials during the design stage. Responses to a questionnaire indicate that the architects are aware of the environmental impacts of building materials, and knowledgeable about possible measures which could help avoid the problems. However, they are not adopting green design approaches. Key policy directions for government, professional bodies, educators and clients are made to enable Singapore architects to apply their knowledge of environmental issues in their design decisions.