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2001 Volume 2 Number 2 QUASI-RATIONAL BEHAVIOUR IN THE PROPERTY AND CONSTRUCTION MARKET FROM AN ECONOMIC PERSPECTIVE Raymond Y.C. Tse Department of Building and Real Estate, Hong Kong Polytechnic University Peter E.D. Love School of Architecture and Building, Deakin University, Australia The conclusions of Rafterys experiment, which aimed to demonstrate quasi-rational behaviour in the property and construction markets, are challenged. The authors argue that the behaviour of people used in Rafterys experiment was in fact rational considering their own professional domain of knowledge. The authors explain in economic terms why the behaviour of those involved in Rafterys experiment was rational and why people will behave in a predictable way in the property and construction market. AN ANALYSIS OF CONSTRUCTION PLANT UTILIZATION, STANDING TIME AND CUMULATIVE BREAKDOWN David J. Edwards and Gary D. Holt School of Engineering & the Built Environment, University of Wolverhampton Empirical research in the field of plant management is relatively scarce, albeit the trend in this respect is upward. In adding to the knowledge of plant utilization in that respect, this paper analyses historical utilization data from among a sample of hydraulic excavators operating in the UK opencast mining sector. A total 6,742 observations of machine utilization status represented the primary data. Analysis revealed these machines were available for an average 50 hours per week. On average, the sample machines worked for 75 per cent of this available time, were standing idle for 20 per cent of the time and broken down the remaining 5 per cent. Average breakdown time during the first 9,100 hours of machine life was between 5 and 10 hours per week. There is a general increase in breakdown with machine age. A cubic equation is shown to accurately model breakdown trend over machine life and the potential application of this model for construction practitioners is discussed. Indications for future research are given and it is concluded, that greater formalization of record keeping (and hence generation of history-file-data) is required in the plant sector. CERTIFIED SKILLS OF PLANT OPERATORS FOR MAINTAINING CONSTRUCTION PLANT Ruel R. Cabahug, David J. Edwards and Gary D. Holt SCHOOL OF ENGINEERING AND THE BUILT ENVIRONMENT, UNIVERSITY OF WOLVERHAMPTON, UK Adequately trained plant operators are prerequisite to achieving high production rates in any industry. However, previous research has revealed that many plant managers are reluctant to invest in operator training; this is because of the prejudicial view that training is expensive and often fails to produce the desired results. In the UK construction industry, training certification is not mandatory. Further, formally administered training of plant operatives within the UK does not always produce the skills needed by the industry. Consequently, many plant and equipment operators tend to learn informally from their peers (that is, by other more experienced operatives who are often not formally trained themselves). Operator knowledge and skill therefore is generally acquired through trial, error and experience. This approach represents a poor alternative to formal training, since there is little consensus as to what operator attributes actually determine competence. Negative ramifications of the poorly trained operative include: reduced production output; greater potential risk to safety (both operators and their site colleagues); and severe financial damages in the event of injury or damage to property. This paper reviews the relationship between operator skill and current maintenance activities in the UK construction industry, albeit inherent linkage to maintenance philosophies utilised in other industries (e.g. manufacturing and process) is inevitable in such discussion. The study critically appraises current plant operator certification schemes and provides recommendations for improving plant operator training and education. EVALUATION CRITERIA OF PUBLIC-SECTOR DESIGN AND BUILD PROJECTS IN HONG KONG Albert P. C. Chan (1), Danny C. K. Ho (1), and C.M. Tam (2) (1) Department of Building and Real Estate, Hong Kong Polytechnic University. (2) Department of Building and Construction, City University of Hong Kong. This study examines the views of clients and contractors on evaluation criteria of public-sector design and build (D&B) projects in Hong Kong, obtained through a questionnaire survey. The results indicate that both clients and contractors consider project delivery time, certainty of project delivery time, conformance to users expectations, certainty of project cost, and project cost as the top five evaluation criteria. These criteria are also shared by U.S. and U.K. clients as reported in past studies, which implies that a common yardstick of D&B project success is emerging. This consensus shows that contractors understand the most important achievements that public sector clients require for D&B projects in Hong Kong. Project participants focus on time performance seems to be a distinct evaluation criterion for D&B projects. A general agreement between the reasons for using D&B method and the assessment criteria was also observed. USING INFORMATION TECHNOLOGY TO OVERCOME DIFFICULTIES IN VALUE MANAGEMENT STUDIES - HONG KONGS EXPERIENCE QiPing Shen and Jacky K.H. Chung Department of Building and Real Estate, The Hong Kong Polytechnic University This paper introduces findings from a recent research study of the difficulties encountered in Value Management (VM) studies and the useful Information Technology (IT) tools that can be applied to overcome these difficulties. The study was conducted by using a structured questionnaire and a number of follow-up interviews and focus group meetings with two groups of people. The first group consists of members of the Hong Kong Institute of Value Management (HKIVM) experienced in VM studies. The second group consists of construction professionals who have obtained comprehensive knowledge of VM, but have less experience in VM studies. Findings from this study are also discussed in the light of views from several international members of VEAMAC (Value Engineering, Analysis, Management Academic Community). Finally, suggestions on how IT can be used as an enabling tool to overcome difficulties in VM studies are made based on the findings. CONBPS -A NEW PROCESS SYSTEM FOR BUILDING PROJECTS Joanna Poon (a), Keith Potts (b), Peter Musgrove (b), Patricia Cooper (c) a School of Engineering and the Built Environment b School of Computing and Information Technology c School of Art and Design University of Wolverhampton, UK. The construction industry in the UK needs to improve its performance and provide clients with an improved level of satisfaction. The inefficient design and construction process is usually criticised as one of the main causes of poor performance. Modelling the construction process has been a popular topic during the past decade. Previous research has focused on modelling the process only while more recent research has considered the roles of construction parties as well. A new construction process system, CONstruction Best Practice System (CONBPS), has been developed based on the use of an expert system. This model clearly identifies the roles and responsibilities of the major parties within the building team and identifies the activities and the key issues within the project cycle. The completed model will reflect the full project cycle from inception to completion. CONBPS is based on the traditional building procurement strategy with the clients architect completing the design and the contractor responsible for the construction work. The traditional procurement strategy has been investigated because it is still probably the most popular procurement method in the U.K. and yet it is subject to most criticism. The primary aim of this paper is to discuss the development of the CONBPS prototype. SCHEDULING THE TRUCKMIXER ARRIVAL FOR A READY MIXED CONCRETE POUR VIA SIMULATION WITH @RISK S.Q. Wang, C.L. Teo and G. Ofori Department of Building, National University of Singapore Ready mixed concrete (RMC) placing is a major operation in many big cities. As the truckmixer is the only means to deliver RMC batched remotely in batching plants to sites, the matching of RMC supply to site requirement is crucial not only for truckmixer operators but also for sites and batching plants to improve their productivity or efficiency. From field studies in Hong Kong, Beijing and Singapore (Wang, et al., 2000, 2001), this matching was found to be difficult to achieve and it depends fundamentally on the proper scheduling of truckmixers arrival pattern (interarrival time) for a typical RMC pour. This paper presents a simulation model, using spreadsheet add-in software @Risk, to further analyze the effect of the arrival pattern on the RMC placing productivity and determine the best truckmixers interarrival time based on data collected in Singapore. The simulation results show that the truckmixers arrival pattern is most important in determining the productivity of the RMC placing equipment and this is especially true for the arrivals of the first several truckmixers. The best interarrival time of truckmixers for pumped pours in Singapore was found to be 11 minutes, which could reduce the average number of truckmixers queuing on site to only two while ensuring the utilization of pump at a relatively high level of 92%. Given the advantages of spreadsheet and @Risk, the model is easy to understand and simple to operate. It can assist contractors and batching plant personnel in better scheduling the truckmixers, and can also be easily modified to analyze other factors affecting the RMC placing productivity. FACTORS THAT ARCHITECTS CONSIDER WHEN RECOMMENDING CONSULTANTS TO CLIENTS Yean Yng Ling Department of Building, National University of Singapore And Marie P S Lim PWD Consultants Pte Ltd, Singapore The contribution of this paper is the identification of the important attributes that architects consider when they recommend consultants such as quantity surveyors and engineers to clients. A postal survey of architects who practice in Singapore was conducted to gauge whether they felt that the 44 attributes identified from literature review were important. The principal finding is that 33 of the 44 attributes identified are important. Consultants need to excel in task performance comprising general mental ability, job knowledge, task proficiency and job experience criteria, and contextual performance comprising conscientiousness, initiative, communication skills, social skills and commitment criteria. They also need to have prior working relationships and harmonious relationships with clients and other consultants in the project team. It is not important for consultants to quote low fees. The practical implication is that in order for consultants to be recommended by architects to clients, they should instead concentrate on hard and soft skills. Consultants also need not waste time expanding the size of their companies or networking with architects, as the study found that these are not important. Architects prefer to rely on more meritocratic means of selecting consultants, and factors such as social relationships, kinship ties, reciprocating favours or potential future business opportunities are not important. EFFECTIVENESS OF JOINT VENTURES AS CONSTRUCTION TECHNOLOGY TRANSFER VEHICLES: THE CASE OF SINGAPORE George Ofori, Teo Pin and Christopher Leong Department of Building, National University of Singapore Joint ventures between foreign and local construction firms are often considered to be an effective way to transfer technology from the former to the latter, thus helping the latter to upgrade. However, it is realised that the process is fraught with problems. This paper considers the effectiveness of foreign-local joint ventures in the transfer of construction technology in Singapore. It is based on a postal questionnaire survey of foreign and local contractors, clients and consultants. The study found that joint ventures have been beneficial to local contractors. It recommends measures to enhance their usefulness as technology transfer vehicles. SENSITIVITY OF THE FE SOFTWARE IN GROUND FREEZING H . Malekzadeh, F. C. Harris and D. J. Edwards Built Environment Research Unit, School of Engineering and Built Environment University of Wolverhampton, UK. This paper describes sensitivity analysis carried out on FEM (Finite Element Method) models in the field of civil and mining engineering using the ABAQUS software package. Specifically, worked geotechnical modelling examples were selected from the literature and the effects of varying the influential parameters examined for their impact on ground freezing (e.g. thermal conductivity, latent heat, specific heat, permeability, thaw settlement rate, etc.). The models mainly concentrated on consolidation of unfrozen soil, ice-wall formation, ground movement due to freezing loading and creep with acceptable results being demonstrated. DEVELOPING A COST-TIME MODEL FOR ESTIMATING CONSTRUCTION DURATIONS OF SEWERAGE PROJECTS IN PERTH, WESTERN AUSTRALIA Yousef, G., Water Corporation, Perth, Western Australia and David Baccarini, Curtin University of Technology, Perth, Western Australia School of Architecture, Construction & Planning, Curtin University of Technology, PO Box U 1987, Perth 6845, Western Australia, E-mail bacco@arch.curtin.edu.au Estimating the duration of construction projects is important for good project management. Previous work has modelled the construction duration of projects by a time-duration formula (T=KxCB) originally proposed by Bromilow (1969). In this research, this model was applied to a sample of 46 sewerage projects undertaken by a government agency in Perth, Western Australia. It was found that a relationship in the form of (T=158.85 x C 0.5367) exists. The model was also tested against 65 future projects where in-house project managers had produced estimated costs and durations. It was found that the model predicts higher durations than those predicted by the project managers. *** |