Journal Papers by Vahid Faghihi
Journal of Green Building, 2022
The BIM building envelope integrates a BIM building's internal and external environments, improvi... more The BIM building envelope integrates a BIM building's internal and external environments, improving energy efficiency and substantially lowering energy usage. This research aimed to assess the energy efficiency of typical building envelope materials in Iran. To do this, we used Autodesk Revit® to generate a generic model and DesignBuilder® to conduct an energy analysis.
The BIM building envelope integrates a BIM building's internal and external environments, improving energy efficiency. A BIM building envelope energy analysis was performed on 58 local wall constructions material in Iran. Then, the energy consumption of a BIM building's HVAC system was then compared against the costs of all external wall alternatives to determine the optimal layer combination. Consequently, the energy simulation results demonstrated that the double external wall structure, 2AAC block core, with XPS (CFC) insulation exterior wall and the single external wall, PERLEX Ultra-Lightweight (PUW) wall performed better. In addition, the clay block wall is found to be the optimum solution for the case study location. The applicability of the proposed system is validated with a case study of a traditional residential building.
Sustainable Cities and Society, 2022
With infrastructure services demand rising, a significant contributor to sustainable development ... more With infrastructure services demand rising, a significant contributor to sustainable development goals, infrastructure systems have to evolve and adapt effectively, efficiently, and sustainably. The broad set of decision variables coupled with the trade-off among the economic, social, and environmental aspects complicate sustainability assessment and optimization during the design stage. Thus, this paper presents a Building Information Modeling (BIM)-based automated framework for real-time evaluation and optimization of sustainability in infrastructure projects. The proposed framework benefits from infrastructure sustainability rating systems that provide a systemic and balanced set of indicators for careful consideration of sustainability. On the other hand, to automate the process, BIM, with its 3D shared environment, is used as an integrated platform for dynamic sustainability analysis. The proposed framework integrates both novelties in real-time during the early design stages, which helps designers to select the most sustainable alternative. A prototype and a hypothetical case study are conducted to validate the framework's applicability through Infraworks 360 as the operating BIM platform and Envision as the baseline rating system. The results confirm that adopting the suggested method simplifies the inclusion of sustainability into design decisions while facilitating documentation of compliance with credit assessment for both project teams and verification agencies.
Journal of Legal Affairs and Dispute Resolution in Engineering and Construction, 2022
Building information modeling (BIM) is a technology and process that creates profound changes in ... more Building information modeling (BIM) is a technology and process that creates profound changes in construction methods, directly affecting the optimization of the execution procedure and the methods outlined in construction project contracts. There is a lack of manuals for implementing BIM contracts in most developing countries. This lack of instruction has led to a slow acceptance and implementation of BIM in many developing countries. Previous studies have determined present challenges in relations, roles, and risks of a BIM-focused contract. Thus, this research investigates and determines how these contractual challenges may affect the implementation procedure and, ultimately, the successful execution of the contractual obligations relating to the use of BIM in projects. Accordingly, after a comprehensive literature review and listing the identified challenges, two sets of data collection from construction companies were used to define the effects of BIM contractual challenges. Consequently, data verification of the contractual challenges in these two case projects indicates a rise in BIM success due to its superior handling of project execution compared to how non-BIM projects handle similar challenges.
Journal of Structural and Construction Engineering, 2022
Lack of correct understanding of the final product of projects is one of the most important cause... more Lack of correct understanding of the final product of projects is one of the most important causes of cost overrun in the construction industry, which is the source of many differences between the main elements of projects. The use of new technologies has helped developed countries control the cost of projects. Virtual reality is one of the latest technologies which has entered many industries such as the construction industry in recent years and has positive effects in different areas of project management such as cost management. According to the critical capabilities of these projects in the field of creating a correct understanding of the final product, as well as the strong influence of the finishing on increasing the cost of construction projects, the present study is limited to investigating the effect of virtual reality on cost reduction in the finishing stage of residential projects. Firstly, to achieve the study's objectives, 39 causes of increasing the cost of construction projects were extracted by studying the previous literature. Rework, design changes during execution, and fluctuations in material prices were identified as the most influential factors in growing joinery projects' costs. Then, ten experienced experts validated the accuracy of the results using a questionnaire. Second, a platform was designed to implement virtual reality to provide a correct image of the project product and management information. Then, by an interview, the effect of virtual reality on reducing the cost of finishing residential projects was measured. Finally, by merging the first and second steps of the research, the results showed that virtual reality through reduction of design changes during implementation, rework, and mistakes in virtual reality design have a significant impact on reducing project costs. Also, 25 factors that have not impacted this technology and five other factors that have experienced minimal impact were separated.
Journal of Simulation , 2022
The capability trap relegates organisations to poor performance by preventing feedback loop domin... more The capability trap relegates organisations to poor performance by preventing feedback loop dominance shifts from working harder to working smarter. Escaping the trap is difficult because of the feedback structure that creates the trap, managerial biases, and delays in exploiting high leverage solutions. Previous research analysed cases of existing systems captured by or escaped from the trap, primarily to identify and explain trapping mechanisms. The current work approaches different by investigating how systems can be designed a priori to avoid or better escape the trap. We modeled a sustainability improvement program that successfully avoided capture and identified escape scenarios. The simulation model analysis identified high leverage improvement design features for trap avoidance and escape. Building efficiency features such as energy-saving effectiveness, decreasing life-cycle costs, increasing improvement lifespans, and conservation effectiveness influence performance. Improvement program design guidelines to escape or avoid the trap are proposed, and future research opportunities are discussed.
Construction Management and Economics, 2020
Programs to improve the sustainability of building infrastructures often consist of project portf... more Programs to improve the sustainability of building infrastructures often consist of project portfolios that need to be prioritized in an appropriate chronological fashion to maximize the program's benefits. This is particularly important when a revolving-fund approach is used to leverage savings from the initial projects to pay for later improvements. The success of the revolving-fund approach is dependent on the appropriate prioritization of projects. Competing performance measures and scarce resources make this task of project prioritization during the planning stage a complex and challenging endeavour. The current study examined the impact of different project prioritization strategies for revolving-fund sustainability program performance. A novel modeling approach for sustainability decision-analysis was developed using the system dynamics method, and the model was calibrated using a campus sustainability improvement program at a major university. The model was applied to evaluate the effects of five common project-prioritization strategies on three program-performance measures, across a wide range of initial investment levels. For the university case study, we found that the strategy of prioritizing projects according to decreasing benefit/cost ratio performed best. The research demonstrated that using a system dynamics model can allow sustainability program managers to make better-informed sequencing decisions, leading to a financially and environmentally successful program implementations.
Wiley StatsRef: Statistics Reference Online, 2018
Construction project scheduling is one of the most important tools for project managers in the ar... more Construction project scheduling is one of the most important tools for project managers in the architecture, engineering, and construction (AEC) industry. Construction schedules allow project managers to track and manage the time, cost, and quality (i.e., the project management triangle) of projects. Developing project schedules is almost always troublesome, as it is heavily dependent on project planners' knowledge of work packages, on-the-job experience, planning capability, and oversight. Having a thorough understanding of the project geometries and their internal interacting stability relations plays a significant role in generating practical construction sequencing. On the other hand, the new concept of embedding all the project information into a three-dimensional (3D) representation of a project (also known as building information model or BIM) has recently drawn the attention of the construction industry. It seems timely to use this source of project data for generating better construction schedules. In this article, the authors demonstrate how to develop and extend the usage of the genetic algorithm (GA), not only to generate construction schedules, but also to optimize the outcome for different objectives (i.e., cost, time, and job-site movements). The proposed methodology initially generates structurally stable construction schedules and then optimizes these schedules based on three distinct project management objectives. The basis for the GA calculations is the embedded data available in the BIM of the project, which should be provided as an input to the algorithm. By reading the geometric information in the 3D model and more specific information about the project and resources from the user, the algorithm results in various construction schedules. The output 4D animations and schedule quality scores can further help the user to find the most suitable construction schedules for the given project.
Finding the optimized trade-off relationship between cost and time, two important objectives of c... more Finding the optimized trade-off relationship between cost and time, two important objectives of construction projects, helps project managers and their teams select a more suitable schedule for a given project. This trade-off relationship can roughly be estimated using past and cumulative knowledge, but since the early 1970s, researchers have been working on a systematic and mathematical solution to define this relationship more accurately. These researchers have used different optimization techniques such as the genetic algorithm (GA), ant colony, and fuzzy logic to further explore the relationship. In the present paper, the authors have used their previously introduced construction schedule generator algorithm to present graphical relationships between pre-defined objectives of schedule optimizations. The process starts with developing construction schedules from the project's Building Information Model (BIM) as part of the input along with resource data. Then the process continues with optimization of all developed construction schedules according to the two mentioned objectives along with the introduced job-site movement objective, which mathematically helps the sequence of installation be more logical and practical. Finally generation of a 3D space for all the created and calculated construction schedules in the form of a 3D solution cloud point. These 3D construction schedules show solution cloud points and three Pareto Fronts for the given project.
Automating the development of construction schedules has been an interesting topic for researcher... more Automating the development of construction schedules has been an interesting topic for researchers around the world for almost three decades. Researchers have approached solving scheduling problems with different tools and techniques. Whenever a new artificial intelligence or optimization tool has been introduced, researchers in the construction field have tried to use it to find the answer to one of their key problems – the “better” construction schedule. Each researcher defines this “better” slightly different. This article reviews the research on automation in construction scheduling from 1985 to 2014. It also covers the topic using different approaches, including case-based reasoning, knowledge-based approaches, model-based approaches, Genetic Algorithms, Expert Systems, Neural Networks, and other methods. The synthesis of the results highlights the share of the aforementioned methods in tackling the scheduling challenge, with Genetic Algorithms shown to be the most dominant approach. Although the synthesis reveals the high applicability of Genetic Algorithms to the different aspects of managing a project, including schedule, cost, and quality, it exposed a more limited project management application for the other methods.
Reducing energy consumption is critical to improving the sustainability of built infrastructures.... more Reducing energy consumption is critical to improving the sustainability of built infrastructures. Both increased efficiency and conservation by users can contribute. This work investigates feedback in the design of energy improvement programs that exploit efficiency and conservation by developing a system dynamics model. The model formalizes the paid-from-savings approach and is validated using a sustainability program at a major university. Model simulations investigate the impacts of five program designs on two forms of performance measure (energy savings and monetary savings) and capital requirements. Results reveal the importance of both the timing and relative strength of two critical reinforcing feedback loops. Results recommend the consideration of the integrated use of conservation and efficiency under capital constraints. This result suggests a generic pair of linked reinforcing loops and their staged activation as an advanced solution to the dynamic challenges of sustainable improvement program design.
Expert Systems With Applications, Nov 15, 2014
The construction project schedule is one of the most important tools for project managers in the ... more The construction project schedule is one of the most important tools for project managers in the Architecture, Engineering, and Construction (AEC) industry that makes them able to track and manage the time, cost, and quality (a.k.a. Project Management Triangle) of projects. Developing project schedules is almost always troublesome, since it is heavily dependent on project planners’ knowledge of work packages, on-the-job-experience, planning capability and oversight. Having a thorough understanding of the project geometries and their internal interacting stability relations plays a significant role in generating practical construction sequencing. On the other hand, the new concept of embedding all the project information into a 3-dimentional representation of a project (a.k.a. Building Information Model or BIM) has recently drawn attention to the construction industry.
In this paper, the authors demonstrate a novel approach of retrieving enough information from the BIM of a project and then develop construction sequencing for the installation of the project elements. For this reason a computer application is developed that can automatically derive a structurally (statically) stable construction sequence, using the concept of the Genetic Algorithm (GA). The term “structurally stable sequencing” in this article refers to the sequencing order of erection in which the structure remains statically stable locally and globally during the entire installation process. To validate the proposed methodology, the authors designed 21 different experiments and used the proposed method for generating stable construction schedules, which all were successfully accomplished. Therefore, this methodology proposes a novel approach of construction project application of the GA, as an Expert System tool.
Effective teaching of engineering concepts relies both on carefully designed lesson plans that me... more Effective teaching of engineering concepts relies both on carefully designed lesson plans that meet specific learning outcomes, and on classroom activities that students find engaging. Without student engagement, even the best designed plans will fail to meet their outcomes. In other words, students need to be actively involved in the learning process. The objective of this paper is to present a case study of applying a novel active learning method, specifically educational prediction markets (EPM), for teaching project management classes at a major research university. This method was investigated for its effectiveness in engaging students, as well as promoting learning of probabilistic reasoning without explicit teaching. Student surveys, following the EPM implementation, revealed both advantages and disadvantages. The two key benefits reported by the students were: a) providing better connections between the materials taught in the class and realities of construction projects, and b) increasing overall interest and enthusiasm in learning about project risk management due to the game-like nature of the process. The main disadvantage was disengagement by a subset of students due to perceptions that fellow students were manipulating the market results.
Market diversification is considered as a method to reduce risks regarding to the portfolio and p... more Market diversification is considered as a method to reduce risks regarding to the portfolio and projects. The diversification strategy of firms might affect revenue and market new entries of the companies. Unfortunately, there are few empirical findings regarding diversification of international construction companies. The current study performs an empirical analysis on diversification of international contractors and design firms. The study identifies (1) the pattern of contractors classified into business types, (2) the relationship between diversification level and size of the company, and (3) market entry strategy of US firms. The empirical study findings may be a start to investigation of diversification strategies of construction companies.
Conference Papers by Vahid Faghihi
30th International Symposium on Automation and Robotics in Construction (ISARC 2013), Aug 2013
SatraPM is a web-based software package, aiming to help project managers to easily handle their c... more SatraPM is a web-based software package, aiming to help project managers to easily handle their construction projects via internet. This software is capable of handling all projects of an organization, in which all projects can be defined in EPS the same as users in OBS. A 3D accessing module links EPS, OBS and inherent functions in order to provide a secure environment for the data to be processed throughout the system. This paper intends to take a deeper look at capabilities of SatraPM in helping project managers to keep track of and control their construction projects as well as its potential future features.
30th International Symposium on Automation and Robotics in Construction (ISARC 2013), Jul 2013
As the usage of BIM increased in the construction industry, some construction owners started expl... more As the usage of BIM increased in the construction industry, some construction owners started exploring the use of BIM for maintaining their facilities. Construction Operations Building Information Exchange (COBIE), a spreadsheet data format suggested in 2007 to manipulate building information, is considered as one of the solutions that would facilitate the process of transferring information from BIM to applications for facilities management. Several BIM and Computer Aided Facilities Management (CAFM) applications offer functions to export or import the COBIE data. To facilitate the process of generating the COBIE data out of Building Information Model, some add-in applications, such as COBIE Toolkit for Revit, also were developed. However, most of these applications handle a limited amount of COBIE data. Professionals using these add-in applications therefore sometimes end up spending a significant amount of time to add additional data manually to the COBIE data file. To automatically get a data-rich COBIE file, we developed a prototype application that extracts information from Revit, which is one of the BIM authoring tools, stores them in an external database, and then produces the COBIE file using information stored in the database. We applied our application to a pilot project and produced 8 COBIE worksheets automatically, which demonstrated a significant amount of time saving. This paper presents how our prototype application produces 8 COBIE data sets automatically. It also addresses our attempt to handle more COBIE data sets.
The 30th International Conference of the System Dynamics Society, Jul 2012
The impacts on energy generation and use on sustainability, increasing energy demand, and declini... more The impacts on energy generation and use on sustainability, increasing energy demand, and declining natural resources have made energy improvements a top priority for many organizations. But adequate financing for sustainability improvement projects for built infrastructures is not available. The Paid-From-Savings approach can leverage savings to pay for energy improvements. Although well established and adopted by many organizations, an incomplete understanding of the dynamics of these revolving fund programs hinders their effective and efficient use. In the current work the Harvard Green Campus Initiative and a Texas A&M University sustainability improvement programs were used to develop a dynamic model of a revolving sustainability fund. The validated model is used to test the effectiveness of three project planning strategies and two financing alternatives. Results indicate that with adequate funding it was most advantageous to proceed with all projects as quickly as possible and that with insufficient initial funding the best strategy depended upon the program objectives (e.g. earliest completion, largest fund, minimum negative fund balance). Contributions to sustainability and system dynamics modeling and future research opportunities are discussed.
Third International Conference on Construction in Development Countries, Jul 2012
Although many contractors in the U.S. have reported their successful implemetations of Building I... more Although many contractors in the U.S. have reported their successful implemetations of Building Information Modeling (BIM) in construction, they seldom presented challenges and failures they went through. Those contractors, especially in the developing countries, who try to apply BIM to their projects for the first time, could assume that they would get the same success easily as soon as they start using BIM applications. In practice, however, no contractors can apply BIM to their projects from the beginning unless they figure out what BIM can do, what exactly they want to accomplish using BIM, what challenges they would face, and how they should handle those challenges. This paper explores five challenges that contractors in the developing countries may need to discuss before they apply BIM to their projects.
eWork and eBusiness in Architecture, Engineering and Construction (Proceedings of the 5th European Conference on Product and Process Modelling in the Building and Construction Industry), Jul 2012
One of the reasons why some construction professionals are excited about BIM is because of its ab... more One of the reasons why some construction professionals are excited about BIM is because of its ability to visualize the installation of prefabricated building modules. As far as using BIM for facilitating the prefabrication process, we expect that all building components are installed correctly as indicated in the model. However, in many cases, building components such as cast-in-place concrete beams and columns are installed a little bit inaccurately because the formworks can be sagged or twisted while fresh concrete is being placed. Our research tested how effectively BIM and Robotic Total Station technology would facilitate to advance the quality control practices on field. For this investigation, we invited three Robotic Total Station technology venders to a 107,000-square-foot academic building construction project jobsite. Our test confirmed that the use Robotic Total Stations expedited the process of marking the layout points on the jobsite or collecting point data from existing facilities. Along with the results of our test, this paper also presents some lessons we learned from the field test.
Non-English Papers by Vahid Faghihi
3rd International Conference of Project Management, 2007
Proceedings of the 5th International Conference of Project Management, 2009
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Journal Papers by Vahid Faghihi
The BIM building envelope integrates a BIM building's internal and external environments, improving energy efficiency. A BIM building envelope energy analysis was performed on 58 local wall constructions material in Iran. Then, the energy consumption of a BIM building's HVAC system was then compared against the costs of all external wall alternatives to determine the optimal layer combination. Consequently, the energy simulation results demonstrated that the double external wall structure, 2AAC block core, with XPS (CFC) insulation exterior wall and the single external wall, PERLEX Ultra-Lightweight (PUW) wall performed better. In addition, the clay block wall is found to be the optimum solution for the case study location. The applicability of the proposed system is validated with a case study of a traditional residential building.
In this paper, the authors demonstrate a novel approach of retrieving enough information from the BIM of a project and then develop construction sequencing for the installation of the project elements. For this reason a computer application is developed that can automatically derive a structurally (statically) stable construction sequence, using the concept of the Genetic Algorithm (GA). The term “structurally stable sequencing” in this article refers to the sequencing order of erection in which the structure remains statically stable locally and globally during the entire installation process. To validate the proposed methodology, the authors designed 21 different experiments and used the proposed method for generating stable construction schedules, which all were successfully accomplished. Therefore, this methodology proposes a novel approach of construction project application of the GA, as an Expert System tool.
Conference Papers by Vahid Faghihi
Non-English Papers by Vahid Faghihi
The BIM building envelope integrates a BIM building's internal and external environments, improving energy efficiency. A BIM building envelope energy analysis was performed on 58 local wall constructions material in Iran. Then, the energy consumption of a BIM building's HVAC system was then compared against the costs of all external wall alternatives to determine the optimal layer combination. Consequently, the energy simulation results demonstrated that the double external wall structure, 2AAC block core, with XPS (CFC) insulation exterior wall and the single external wall, PERLEX Ultra-Lightweight (PUW) wall performed better. In addition, the clay block wall is found to be the optimum solution for the case study location. The applicability of the proposed system is validated with a case study of a traditional residential building.
In this paper, the authors demonstrate a novel approach of retrieving enough information from the BIM of a project and then develop construction sequencing for the installation of the project elements. For this reason a computer application is developed that can automatically derive a structurally (statically) stable construction sequence, using the concept of the Genetic Algorithm (GA). The term “structurally stable sequencing” in this article refers to the sequencing order of erection in which the structure remains statically stable locally and globally during the entire installation process. To validate the proposed methodology, the authors designed 21 different experiments and used the proposed method for generating stable construction schedules, which all were successfully accomplished. Therefore, this methodology proposes a novel approach of construction project application of the GA, as an Expert System tool.