节约型工程建设管理途径研究

通过分析节约型工程建设内涵,从工程建设宏观管理角度出发,提出推进项目管理、改革政府投资工程项目组织实施方式和注重既有建筑的维护、改造再利用3种管理途径,以推进节约型工程建设,使得社会资源和能源得到高效利用。     

An integrated ergonomics framework for evaluation and design of construction operations

Labor is one of the most critical resources in the construction industry due to its impact on the productivity, safety, quality, and cost of a construction project. Ergonomic assessment, as a tool and method for analyzing human activities and their interactions with the surrounding environment, is thus crucial for designing operations and workplaces that achieve both high productivity and safety. In construction, however, the constantly changing work environments and laborious tasks cause traditional approaches to ergonomic analysis, such as manual observations and measurements, to require substantial time and effort to yield reliable results. Therefore, to simplify and automate the assessment processes, this study explores the adaptation and integration of various existing methods for data collection, analysis, and output representation potentially available for comprehensive ergonomic analysis. The proposed framework integrates sensing for data collection, action recognition and simulation modeling for productivity and ergonomic analysis, and point cloud model generation and human motion animation for output visualization. The proposed framework is demonstrated through a case study using data from an off-site construction job site. The results indicate that integrating the various techniques can facilitate the assessment of manual operations and thereby enhance the implementation of ergonomic practices during a construction project by reducing the time, effort, and complexity required to apply the techniques.     

The influence of personal characteristics on effectiveness of construction site managers

It has been suggested that construction site managers' career progression may be affected because of the existence of certain personal characteristics that conform to industry stereotypes. These stereotypes need to be identified and examined in a systematic manner to ensure that the rationality of human resource management policy is indeed justifiable. A set of 26 personal characteristics believed to influence the effectiveness of construction site managers is identified by senior construction managers using the nominal group technique. These characteristics are tested for correlation with effectiveness using a non-results-based effectiveness index. A questionnaire survey was completed by 61 site managers for this purpose. The results suggest that of 26 identified personal factors believed to be important the only ones which may actually be related to effectiveness are: involvement in continuing professional development, number of firms worked for, use of addictive substances, education level, membership of professional bodies, job satisfaction, motivation level, career aspiration, stress level, leadership style and the need to work. The findings will assist those recruiting, retaining or promoting site managers to make a more informed judgement of key factors influencing effectiveness.     

Sharing of Temporary Structures: Formalization and Planning Application

Sharing temporary structures minimizes the risks and costs associated with their set-up and break-down. Yet sharing makes temporary structure planning and re-planning more complex, as construction engineers need to understand the conditions of activities to determine the accessibility and sharing possibilities. BIM (building information modeling) technology can extract and process geometric and action data in 3D models. Using BIM can increase consistency and speed in identification of sharing solutions for temporary structures. At present, the construction industry does not leverage advances in BIM for planning temporary structures because it lacks formalization that defines key properties and relationship variables for sharing. In this paper, the geometric and action conditions affecting temporary structure sharing are examined to put forth a formalization for a computer application (a proprietary tool developed by the primary author) called the Temporary Structure-Planning Generator (TSPG). The formalization for the TSPG allows construction engineers to rapidly generate multiple temporary structure-sharing options with a selection consistency not yet seen in current construction practice.     

Simulation-based construction productivity forecast using Neural-Network-Driven Fuzzy Reasoning

Fuzzy models and Artificial Neural Network (ANN) systems are two well-known areas of soft-computing that have significantly helped researchers with decision-making under uncertainties. Uncertainty, an ever-present factor in construction projects, has made such intelligent systems very attractive to the construction industry. Estimating the productivity of construction operations, as a basic element of project planning and control, has become a remarkable target for forecasting models. A glimpse into this interdisciplinary field of research exposes the need for a system, that (1) models the effect of qualitative and quantitative variables on construction productivity with an improved accuracy of estimation and (2) has the ability to deal with both crisp and fuzzy input variables in one single framework. Neural-Network-Driven Fuzzy Reasoning (NNDFR), as one of the hybrid intelligent structures, displays a great potential for modeling datasets among which clear clusters are recognizable. The weakness of NNDFR in auto-tuning the design of fuzzy membership functions along with this model's insufficient attention to the optimization of number of clusters has created an area for further research. In this paper, the parameters (fuzzifier and number of clusters) of the proposed system are optimized by using Genetic Algorithm (GA) to fine-tune the system for the highest possible level of accuracy that can be exploited for productivity estimation. The proposed model is also capable of dealing with a combination of crisp and fuzzy input variables by using a hybrid modeling approach based on the application of the alpha-cut technique. The developed model helps researchers and practitioners use historical data to forecast the productivity of construction operations with a level of accuracy greater than what could be offered by traditional techniques.     

Performance Evaluation for Cost Estimators by Reliability Interval Method

Most consultant selection models stress the importance of past performance. However, there are so far very few studies on evaluating consultant’s performance. It hampers the whole process of the selection model. This paper tries to establish a systematic approach in developing a consultant’s performance evaluation model for the evaluation of the performance of cost estimators in the construction industry of Hong Kong. Nominal group technique is adopted in identifying the decision criteria for the evaluation, and a reliability interval method (RIM) is developed to assess the importance weighting of each criterion. The RIM allows statistical analysis and fuzzy assessment of the weight. The results report the weights of each decision criterion and its subcriterion in evaluating cost estimator’s performance. Interestingly, the results show that traditional functions of cost estimator are the least treasured from the clients. Proactive and professional advice is considered to be much more important. The study is highly relevant to industry practitioners in assessing performance of costs estimators, as well as to researchers in further developing the consultant selection model.     

Alliancing in Australia—No-Litigation Contracts: A Tautology?

A project alliance is a business strategy whereby client and commercial participants’ objectives are aligned. This paper takes an alliance project between public and private organizations in Queensland, Australia as a case study and reports the critical factors identified that influence the success of the alliance project. Alliancing is a system that provides a collaborative environment and a framework to adapt behavior to project objectives. It is about sharing resources and experiences, exposing the “hidden” risks. The case study suggests that leadership has a strong influence on the alliance climate. Commitment and action by the Project Alliance Board (and, so, parent organizations) have a strong impact on the team and alliance culture, indicating alliancing has a high chance of failure when there is inadequate support from top management. Like all relational contracting approaches, trust between alliance partners is important. This case study project takes a further step toward reinforcing the trust element by placing a No-Dispute clause in the alliance agreement. A review of the effects of the no-litigation clause upon the project team is presented. The writers conclude that without a positive approach to relationship management, a No-Dispute approach is impossible. Hence, they postulate that a “no-litigation” alliancing contract is essentially tautological, and go on to argue that a no-litigation contract cannot exist without the help of a clear relational vision, that leads to both soft and hard infrastructure to assist in decision making and relationship building.     

Particle Swarm Optimization for Preemptive Scheduling under Break and Resource-Constraints

This paper introduces a particle swarm optimization (PSO)-based methodology to implement preemptive scheduling under break and resource-constraints (PSBRC) for construction projects. The PSBRC under study allows the preemptive activities to be interrupted in off-working time and not to resume immediately in the next working period because all the limited resources are to be reallocated during a break. The potential solution to the PSBRC, i.e., a set of priorities deciding the order to start the activities or restart the interrupted activities, is represented by the multidimensional particle position. Hence PSO is applied to search for the optimal schedule for the PSBRC, in which a parallel scheme is adopted to transform the particle-represented priorities to a schedule. Computational analyses are presented to verify the effectiveness of the proposed methodology. This paper provides an attempt to make use of preemption and break for the resource-constrained construction project with the objective of minimizing project duration.     

Strengths, Weaknesses, Opportunities, and Threats Analysis of Chinese Construction Companies in the Global Market

Recent years have seen a growing trend of Chinese companies making significant inroads into the international construction market. However, comparing to their fast development, only few studies have been reported to introduce the Chinese international construction companies (CICCs) as an emerging competing force. This research, by conducting a strength, weakness, opportunity, and threat analysis, aims to help understand CICCs which have been stereotypically viewed as a somewhat heterogeneous group. Data supporting the analysis were derived from multiple sources including statistical reports, literature review, interviews, and in particular first-hand experience from those who are competing on the forefront. The research opens a window through which all players in the global construction market can perceive internal and external conditions of their Chinese counterpart.     

Particle Swarm Optimization-Supported Simulation for Construction Operations

This study proposes an integration of particle swarm optimization (PSO) and a construction simulation so as to determine efficiently the optimal resource combination for a construction operation. The particle-flying mechanism is utilized to guide the search process for the PSO-supported simulation optimization. A statistics method, i.e., multiple-comparison procedure, is adopted to compare the random output performances resulting from the stochastic simulation model so as to rank the alternatives (i.e., particle-represented resource combinations) during the search process. The indifference zone and confidence interval facilitate consideration of the secondary performance measure (e.g., productivity) when the main performance measures (e.g., cost) of the competing alternatives are close. The experimental analyses demonstrate the effectiveness and efficiency of the proposed simulation optimization. The study aims to providing an alternative combination of optimization methodology and general construction simulation by utilizing PSO and a statistics method so as to improve the efficiency of simulation in planning construction operations.