M.h. Sebt, E. Parvaresh Karan, M.r. Delavar,
Volume 6, Issue 4 (12-2008)
Abstract
Geographic information systems (GIS) are one of the fastest growing computer-based technologies of past two decades, yet, full potential of this technology in construction has not been realized. Based upon GIS capabilities, construction site layout is one of the areas that GIS could be applied. The layout of temporary facilities (TFs) such as warehouses, fabrication shops, maintenance shops, concrete batch plants, construction equipments, and residence facilities has an important impact on the cost savings and efficiency of construction operations, especially for large projects. The primary objectives of this paper are to describe GIS technology and to present application of GIS technology to construction site layout. The study also
delineated the methods of location TFs in construction site. An example application of GIS to location optimization of tower crane and concrete batch plant is provided to demonstrate GIS capabilities as compared with previous models. The spatial and nonspatial data which used in construction site layout process are analyzed and arranged on GIS environment and results showed the GIS can solve site layout problem. Finally, areas of additional research are noted.
S. Malaikrisanachalee, H. Vathananukij,
Volume 9, Issue 1 (3-2011)
Abstract
Java is an object-oriented program that has abundant open-source libraries for application development and 3D model rendering. Spatial database is the database that can efficiently store and manage geographic information data though various spatial data management techniques. This paper explores the rationale of coupling java with spatial database to develop an effective platform for future Building Information Modeling (BIM) application. The paper methodically presents the prototype system integration design to demonstrate how the system can be developed. The paper also meticulously presents the logical and physical data models in designing optimum BIM database for a reinforced concrete building. An 8-storey reinforced concrete building was used as an implementation case study to validate the proposed prototype system design and investigates the implementation issues. The outcome shows that not only the proposed prototype system offers technological advantages over the traditional BIM applications, its open-source solution can also overcome the financial constraint that currently inhibits the implementation of BIM especially for medium and small enterprises.
Sung-Hoon An, Hunhee Cho, Ung-Kyun Lee,
Volume 9, Issue 1 (3-2011)
Abstract
In the early stages of a construction project, the reliability and accuracy of conceptual cost estimates are major concerns for clients and cost engineers. Previous studies applied scoring methods and established common rules or mathematical methods to assess the quality of cost estimates. However, those approaches have some limitations in adapting to real-world projects or require understanding of sophisticated statistical techniques. We propose a Conceptual Cost Estimate Reliability Index (CCERI), a simple, easy-to-use, and easy-to-understand tool that incorporates weights for 20 factors influencing the quality of conceptual cost estimates. The weights were obtained by eliciting experts’ experience and knowledge. Cost data from 71 building projects were used in the analysis and validation of the CCERI. The analysis reveals that a conceptual cost estimate with a CCERI score of less than 3000 has a high probability of exceeding 10% error, and such conceptual cost estimates are unlikely to be reliable. With the CCERI score, a decision maker or a client can recognize the reliability of the conceptual cost estimates and the score can thus support decision making using conceptual cost estimates. In addition, with the CCERI and the relative importance weights of factors affecting the conceptual cost estimates, the estimator can find ways to modify a conceptual cost estimate and reestimate it. These alternatives can decrease the risk in the conceptual estimated cost and assist in the successful management of a construction project.
A. Kaveh, A. Shakouri Mahmud Abadi, S. Zolfaghari Moghaddam,
Volume 10, Issue 1 (3-2012)
Abstract
This paper presents a strategy for using Harmony Search algorithm in facility layout optimization problems. In this paper an
adapted harmony search algorithm is developed for solving facility layout optimization problems. This method finds an optimal
facility arrangement in an existing layout. Two real-world case studies are employed to demonstrate the efficiency of this model.
A comparison is also made to illustrate the efficiency of these strategies in facility layout optimization
A. Kaveh, H. Nasr Esfahani,
Volume 10, Issue 1 (3-2012)
Abstract
In this paper the conditional location problem is discussed. Conditional location problems have a wide range of applications
in location science. A new meta-heuristic algorithm for solving conditional p-median problems is proposed and results are
compared to those of the previous studies. This algorithm produces much better results than the previous formulations.
I. Yitmen,
Volume 10, Issue 4 (12-2012)
Abstract
Learning rapidly and competently has become a pre-eminent strategy for improving organizational performance in the
new knowledge era. Improving dynamic learning capability is an exclusive strategy for corporate success in construction
industry. Thus engineering design firms should implement OL to accomplish a state of readiness for change and develop a
competence to respond and identify future business potentials. This study aims to analyze the relationship between
organizational learning (OL) and performance improvement (PI) in civil engineering design firms of Turkish construction
industry. OL structure in engineering design firms incorporates five constructs: organizational environment, strategy
development and implementation, supportive leadership, leveraging knowledge, and learning capability. The empirical data
was collected through a questionnaire survey conducted to engineering design firms registered to the Turkish Chamber of Civil
Engineers. The hypothesized model relationships were tested using Structural Equation Modeling (SEM). The results show that
each of the variables has a different role and significant positive impact on the OL process and organizational PI. The variables
“Supportive leadership” and “Learning capability” proved to be strongly significant and positively related to organizational
performance in engineering design firms. In engineering design firms, supportive leadership is needed in order to establish a
participative cultural environment that helps design a new form of organization which emphasizes learning, flexibility, and
rapid response. Learning capability is the potential to explore and exploit knowledge through learning flows that make possible
the development, evolution and use of knowledge stocks enacting engineering design firms and their members to add value to
the design business.
J. S. Yi, C. W. Koo, S. H. Park, O. K. Kwon,
Volume 11, Issue 1 (3-2013)
Abstract
Construction industry consists of several phases in which a variety of stakeholders are involved. As construction projects are becoming larger, more complex and more diverse, the design phase has been more important factor for the success of projects than ever before. However, it is considered that most of design work occurred in actual design process is intangible. Such recognition makes the design phase more unsystematic and arbitrary, which finally weakens the competitiveness of whole project.
In order to solve these problems, this study developed a web-based system for integrated design management (IDMS) which consists of 8 modules including design document, schedule, quality, and building permit management. This section is intended to validate the system implementation and its effectiveness. Two characteristics have made this research significantly different from previous studies. First of all, users of the system including architects and other design professionals were continuously involved starting from the development phase to the validation phase. The other unique characteristic is that the actual design project was applied as a test bed in the final verification stage. The research team applied the actual data which had been generated while each business process, and verified the effectiveness of system implementation. The authors expect that such a user-centered approach enable the system more robust and effective.
F. Nasirzadeh, M. Khanzadi, A. Afshar, S. Howick,
Volume 11, Issue 1 (3-2013)
Abstract
This research presents a dynamic mathematical system for modeling and simulating the quality management process in
construction projects. Through sets of cause and effect feedback loops, all factors that internally and externally affect the
quality management process are addressed. The proposed system integrates fuzzy logic with system dynamics simulation
scheme to consider the uncertainties associated with the model parameters and estimation of the extra cost and time due to
quality defects. Quantification of the consequences of the quality failures is performed based on the α-cut representation of
fuzzy numbers and interval analysis. The proposed approach is efficient in modeling and analyzing a quality management
process which is complex and dynamic in nature and involves various uncertainties. The proposed approach is implemented
in a real submarine water supply pipe line project in order to evaluate its applicability and performance. The negative impacts
resulting from quality failures are simulated. These negative impacts are mitigated by the implementation of alternative
solutions.
Zh. Zhang, J. Xu,
Volume 11, Issue 1 (3-2013)
Abstract
To improve the construction efficiency of the Longtan Hydropower Project, this paper studies the multi-mode resourceconstrained
project scheduling problem in its Drilling Grouting Construction Project. A multiple objective decision making model
with bi-random coefficients is first proposed for this practical problem to cope with hybrid uncertain environment where twofold
randomness exists. Subsequently, to deal with the uncertainties, the chance constraint operator is introduced and the equivalent
crisp model is derived. Furthermore, the particular nature of our model motivates us to develop particle swarm ptimization
algorithm for the equivalent crisp model. Finally, the results generated by computer highlight the performances of the proposed
model and algorithm in solving large-scale practical problems.
M. H. Sebt, M. H. Fazel Zarandi, Y. Alipouri,
Volume 11, Issue 3 (9-2013)
Abstract
Resource-Constrained Project Scheduling Problem (RCPSP) is one of the most popular problems in the scheduling phase of any project. This paper tackles the RCPSP in which activity durations can vary within their certain ranges such as RCPSP with variable activity durations. In this paper, we have attempted to find the most suitable hybridization of GA variants to solve the mentioned problem. For this reason, three GA variants (Standard GA, Stud GA and Jumping Gene) were utilized for first GA, and two GA variants (Standard GA, Stud GA) for the second one, and their hybridizations were compared. For this purpose, several comparisons of the following hybridizations of GAs are performed: Standard-Standard GA, Standard-Stud GA, Stud-Standard GA, Stud-Stud GA, Jumping Gene-Standard GA, and Jumping Gene-Stud GA. Simulation results show that implementing Stud-Stud GA hybridization to solve this problem will cause convergence on the minimum project makespan, faster and more accurate than other hybrids. The robustness of the Stud GA in solving the well-known benchmarking RCPSP problems with deterministic activity durations is also analyzed.
K. J. Tu, Y. W. Huang,
Volume 11, Issue 4 (12-2013)
Abstract
The decisions made in the planning phase of a building project greatly affect its future operation and maintenance (O&M)
cost. Recognizing the O&M cost of condominiums’ common facilities as a critical issue for home owners, this research aims to
develop an artificial neural network (ANN) O&M cost prediction model to assist developers and architects in effectively
assessing the impacts of their decisions made in the planning phase of condominium projects on future O&M costs. A
regression cost prediction model was also developed as a benchmark model for testing the predictive accuracy of the ANN
model. Six critical building design attributes (building age, number of apartment units, number of floors, average sale price,
total floor area, and common facility floor area) which are usually available in the project planning phase, were identified as
the input factors to both models and average monthly O&M cost as the output factor. 55 of the 65 existing condominium
properties randomly selected were treated as the training samples whose data were used to develop the ANN and regression
models the other ten as the test samples to compare and verify the predictive performance of both models. The study results
revealed that the ANN model delivers more accurate and reliable cost prediction results, with lower average absolute error
around 7.2% and maximum absolute error around 16.7%, as compared with the regression model. This study shows that ANN
is an effective method in predicting building O&M costs in the project planning phase.
Keywords: Project management, Facility management, Common facilities, Cost modeling.
Gonçalo Sá, João Sá, Jorge de Brito, B. Amaro,
Volume 12, Issue 2 (6-2014)
Abstract
This paper presents an inspection and diagnosis system customized for rendered walls, both interior and external. It classifies all anomalies capable of affecting renderings and most of the likeliest corresponding causes and is supplemented by anomaly-cause and inter-anomaly correlation matrices. In addition, the diagnosis, repair and maintenance techniques suitable for these anomalies are classified. Examples of the files that contain the exhaustive characterization of the anomalies and diagnosis, repair and maintenance techniques are also presented.
The system is the result of an intense literature review, which allowed collecting and organizing the information available on pathology of renders. Next it was validated by mathematical manipulation of the data collected from standard inspections of 55 buildings, in which 150 renderings (100 exterior and 50 interior) were examined.
The system proposed may be included in a proactive maintenance strategy, since it is robust, reliable and has been statistically validated. The systematic structure of this system is innovative and can help the inspector by making his/her work more objective and standardizing procedures.
Anomalies in wall renderings may be prevented/minimized if buildings are properly managed by developing and implementing proactive maintenance plans that cover the following areas: technology (adequate maintenance and repair solutions, including the selection of materials and execution techniques), economy (minimizing running costs) and functionality (appropriate use).
R. Eskrootchi, M. H. Sebt, F. Jazebi,
Volume 12, Issue 3 (9-2014)
Abstract
In different projects the speed of different machinery can be estimated using manufacturer's handbooks and a number of modification factors to consider the environmental effects, type of the project and status of site management. Since the statuses of different factors of the domestic projects are totally different from those of the international projects, there is a wide discrepancy between the determined speed by handbooks and the actual values in the domestic projects. This paper is aimed to develop a fuzzy system to estimate soil excavation rates at earthmoving jobsites. The proposed fuzzy system is based on IF-THEN rules a genetic algorithm improves the overall accuracy. The obtained results clearly revealed the capability and applicability of the proposed system to properly estimate soil excavation speed. The average error of fuzzy system, handbook method and nearest neighbor interpolation are 10 , 92 and 32 percent, respectively.
A. Kaveh, H. Safari,
Volume 12, Issue 3 (9-2014)
Abstract
The paper presents a hybrid-enhanced algorithm based on CSS for discrete problems whit the focus on traveling salesman problem. The CSS algorithm based on some principles from physics and mechanics, utilize the governing Coulomb law from electrostatics and Newtonian laws of mechanics. However, the CSS is more suitable for continuous problems compared with discrete problems. In this paper, we have tried to resolve this defect of CSS algorithm with the help of local search methods and nearest neighbor for discrete problems whit the focus on traveling salesman problem (TSP). To prove the efficiency of the proposed algorithm, results compared with the results of benchmark problems. Then, the proposed algorithm is used to solve the TSP, using as a method for solving the single row facility layout problem (SRFLP). To prove the efficiency, the results are compared with the results of benchmark problems reported in the recent literatures.
A. Ardeshir, M. Amiri, Y. Ghasemi, M. Errington,
Volume 12, Issue 4 (12-2014)
Abstract
In the water industry tunnels can be used to transfer water from a basin to other areas over varying distances. The construction of such tunnels is inherently risky and can result in unpredicted events and incidents. It is therefore necessary that thorough risk assessments are carried out as a priority of the owner, contractor and consultant organization. This is so that, through a systematic and logical plan, they can risk posed by these unforeseen events and incidents. In this paper, the risks and their main causes which are often encountered in such projects are identified and assessed. A fault tree method is applied in order to identify the main causes of events and incidents. By its nature a Risk assessment cannot be defined by absolute values and so fuzzy data must be used in order to calculate the probability of incidence and the severity of the risk. This is done on the four main criteria of time, cost, quality and safety. In order to estimate the significance of each criterion and to calculate the significance of the total influence of risk Analytic Hierarchy Process (AHP) is applied. In this paper the case study of Dasht-e Zahab water conveyance tunnel has been selected for discussion as it was subjected to severe and multiple hazards. The results obtained using the method were validated by conducting different interviews with the field experts. It was concluded that by applying the proposed methodology on the case study the risks of the project can be evaluated in a more methodical and accurate way than could be done without using the method. This approach is therefore recommended for similar types of projects where there are complicated risks that must be thoroughly investigated and understood.
L. Ma, P. Zhang,
Volume 12, Issue 4 (12-2014)
Abstract
This paper aims to develop a quantitative game model for preventing construction project managers from moral hazard problem from the standpoint of construction enterprises in China. The authors analyze the sources of construction managers’ moral hazard behaviors under China’s specific situation on the basis of the principal-agent theory, establish a game theoretic model to analyze the moral hazard problem between construction enterprises and construction project managers, and calculate the equilibrium solution through building up the payoff matrix. Our crucial contribution is a quantitative characterization of risk deposit system and performance appraisal system which help to resolve the moral hazard problem of construction project managers. The solution results show that the probability of moral hazard problem of construction project managers can be reduced after implementing risk deposit system and performance appraisal system. Thus the two systems we proposed can be taken by China’s construction enterprises as the effective measures to resolve moral hazard problem of construction project managers.
H. Naghash Toosi, M. H. Sebt, R. Maknoon,
Volume 12, Issue 4 (12-2014)
Abstract
Project Management knowledge has been used in many project oriented organizations in last two decades across the world. Despite, rate of project success did not change during these years. We believe there is a basic challenge in projects environment for managing them based on its inherent characteristics. In fact, project management knowledge use theories and concepts that are belong to process management world, as a different world. There is no enough attention to project characteristics as a fundamental differentiation for coping projects. Identification of construction projects nature in order to discern variables that create the project behaviors is main concern of the paper.Considering project characteristics in this research revealed construction project nature creates from combination two aspects. First, detecting environmental changes to develop a need and second prepare resources structure to respond the need. Important management challenge in this model is environmental continuous changes that alter the need and exchange resources structure. So, the paper considers how these aspects can be operationalized for developing a dynamic project management model. It gives some ideas about why project complexity might be considered to be increasing, and how construction projects move towards shorter timescales. The effectiveness of the model is verified by applying it for predicting some construction projects behavior. The results of the paper may capable future project managers to test any decision before its applying and lead to a new project management tool for construction projects management.
Dr E. Shakeri, M. Dadpour, H. Abbasian Jahromi,
Volume 13, Issue 1 (3-2015)
Abstract
Employer Organizations have increasingly interested in outsourcing their projects in the form of public-private partnership (PPP) due to various reasons such as compromising the resource limitations, entering new technologies to the organization and reducing risk. Choosing the private sector as one of the most basic steps in the formation of PPP is of great importance. The present study aims to introduce a hybrid model to evaluate and choose the private sector as one of the parties in PPP using a combination of SWOT-AHP analysis, as one of the most powerful tools in identifying the problem environment, and Fuzzy ELECTRE analysis to evaluate the existing candidates to participate in the partnership using the criteria resulted from SWOT analysis. In first step, criteria set by an organization, as a case, to choose appropriate private sector were identified using SWOT method during various meetings with qualified experts. Then, the best choice was selected using ELECTRE method. Finally, obtained results were compared with the PROMETHE method. The results showed the effectiveness of our proposed method to select private partnerships especially positive and negative inter-organizational and outer-organizational factors significantly influence the private sector selection.
M.d. Martinez Aires, M. Lopez Alonso, E. Jadraque Gago, R. Pacheco-Torres,
Volume 13, Issue 2 (6-2015)
Abstract
Workers who carry out manual rebar tying tasks are exposed to muscular-skeletal injuries associated with the use of manual tools and the movements associated with them (force, repetitiveness and awkward wrist postures). This paper presents a background on musculoskeletal injuries directly linked to manual and mechanical rebar tying method is conducted.
The objective of this study is to compare the traditional manual rebar tying method to the innovative mechanical technique. The methodology carried out follows a qualitative and a quantitative analysis of both processes. Firstly, a qualitative analysis is performed by semi-structured interviews to workers. Secondly, a quantitative study is carried out in the region of Andalusia (Spain). This field study includes on-site measurements of lengths of time activities. According to the methodology developed by the International Labour Organization, the work timing is calculated and a comparison is given.
Results state that the operators adapt without difficulty to the mechanical method and it could result in better performance, whilst reducing some of the risks deriving from the manual tying technique.
I. Yitmen,
Volume 13, Issue 2 (6-2015)
Abstract
The purpose of this study is to investigate the influence of cross-cultural communication (CCC) on stakeholder management process (SMP) in international construction projects from the Turkish stakeholders’ perspective. The research is based on a survey of Turkish stakeholders (contractors, consulting engineers, insurance brokers, and financial advisors) operating internationally. The useable survey comprised 141 individual responses from 205 distributed, giving a response rate of 68.78 percent. Structural equation modelling (SEM) is proposed as an effective tool to investigate the relations between various factors of cross-cultural communication and stakeholder management process and data regarding the Turkish stakeholders have been used to demonstrate its applicability. The results demonstrate that “Communication behaviours” and “Communication strategies” proved to be strongly significant and positively related to SMP, whereas “Communication barriers” have significantly negative effect on SMP. Research findings may encourage the principles and practices of CCC between the stakeholders to be adequately recognized and understood by the international contracting firms operating abroad. Although findings reflect the Turkish stakeholders’ perspectives, it is believed that the parameters identified in this study can further be used as a benchmark to conduct similar studies in other countries. Managers of international contracting firms can develop a Cross-cultural Communication Statement (OCQS) to assess, report, and develop cross-cultural communication between stakeholders of a multi-cultural project environment.