Annual Conference of the International Group for Lean Construction, Jul 6, 2020
Production in earthworks projects is a continuous process of strictly sequenced operations perfor... more Production in earthworks projects is a continuous process of strictly sequenced operations performed by heavy machinery on site. The Production Process Evaluation (PPE) index was developed to evaluate these types of processes by quantifying waste in the bottleneck operation. The PPE index is the ratio of the actual production volume to the theoretical maximum production volume, and it is calculated by assessing value adding and nonvalue adding times, actual and theoretical throughput, and shift durations. These are computed using data obtained from machine control systems linked to the roadel information schema, which represents continuous products and processes. The PPE index was implemented on a case study of a water reservoir construction project. The spreading operation was identified as the bottleneck in the process, based on the high levels of inventory waiting for the operation, the high capacity utilization in the operation and the low capacity utilization of the predecessor and successor operations. The PPE index ranged from 45% to 54% during the three weeks of the case study and indicated high levels of waste in the bottleneck and a lack of production management.
Current building design collaboration follows a siloed and sequential workflow, leading to cumber... more Current building design collaboration follows a siloed and sequential workflow, leading to cumbersome manual rework, multiple files and versions, onerous coordination tasks, etc. Designers struggle to meet the demands of modern construction projects in terms of time, cost, quality and sustainability. Interdisciplinary collaboration can be greatly improved through a new paradigm that entails synchronous collaboration with reinvented functions within BIM technologies. To explore this new paradigm, we adopted the design science approach with five steps: (i) literature review, (ii) mockup design, (iii) survey distribution, (iv) focus groups, and (v) data analysis. The results validate the importance of interdomain design change, strongly support the case for the utility of the use case scenarios, and recommend several directions for future research.
Annual Conference of the International Group for Lean Construction, Jun 26, 2023
Production system design, planning and control are limited both by the incomplete situational awa... more Production system design, planning and control are limited both by the incomplete situational awareness of planners and by their inability to predict the range of possible outcomes of their planning and control decisions. With the development of information technologies for monitoring products and processes on construction sites, it is increasingly possible to provide detailed status information describing the as-built products 'as-built' and processes 'asperformed'. This opens the door to applying predictive analytics to provide decision-makers with frequent predictions of the outcomes for a range of changes they might contemplate to the production system design, even during construction. Within the BIM2TWIN project, we are designing and implementing an agent-based simulation engine that is a core component of an Automated Decision Support System. Currently, the simulation can be calibrated to accurately predict the range of likely project durations for a residential construction project. However, certain aspects of the trade crews' performance, particularly with respect to the completion of tasks, appear to differ from the behaviours described by industry experts and encapsulated in the crew agent behaviour tree in the simulation.
After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged sta... more After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged state of building facades rapidly, remotely and accurately. A long-term research effort aims to develop applications that can reconstruct 'as-damaged' BIM models of reinforced concrete (RC) framed buildings based on 'as-built' BIMs and scans of 'asdamaged' states. This paper focuses on a crucial step: generating an initial 'best-guess' for the new locations of the façade structural elements. The result serves as the seed for a recursive process in which the location and damage to each object is refined in turn. Mapping the 'as-built' BIM frame into the 'as-damaged' scan is challenging because each element may have different displacement and damage. The algorithm exploits the topology of RC frames to perform initial mapping of the structural grid onto the damaged facade. The approach was tested on a synthetic dataset prepared from a real earthquake-damaged building. Although successful, it has yet to be tested on other damaged buildings.
Annual Conference of the International Group for Lean Construction, Jul 18, 2018
In the contemporary agenda of airport design, good spatial design is fundamental to properly and ... more In the contemporary agenda of airport design, good spatial design is fundamental to properly and efficiently manage boarding and disembarking processes. It contributes to the Passenger Experience and social sustainability of the terminal itself. This correlates with higher satisfaction levels from the passenger experience. By contrast, current practices of airport design do not properly cope with its requirements and the subsequent operation phase, because the project is not associated with the complete set of stakeholder requirements including the passengers to systematic modelling and management of their experience. The airport terminal is considered a temporary production system, its focus being the transformation of travellers, aimed to maximize the value for passengers, exploiting information management to better accommodate processes and project structuring. In a lean perspective, the terminal is a "flight factory", whose layout is crucial not only for process efficiency but also to achieve higher performance and user satisfaction, the main metrics for quality service evaluation. Considering the multidisciplinary and complex features involved in airport terminal space programming, Lean Design could have important outcomes in the search for project design integration, effective solutions, quality and all-encompassing sustainability. In this paper we discuss a theoretical framework to investigate value delivery in airport terminal design through the integration of lean thinking, constituting the basis for future research on Passenger Experience.
The purpose of the automated, computer-integrated building realization process is to generate, au... more The purpose of the automated, computer-integrated building realization process is to generate, automatically, all the information and the related documents for the design and the construction of a built facility. The paper reviews the concept of the computer controlled realization process and describes the knowledge base of the system employed for this purpose.
Construction Management and Economics, Jul 16, 2020
Building Information Modelling (BIM) has been widely acknowledged as a new paradigm to transform ... more Building Information Modelling (BIM) has been widely acknowledged as a new paradigm to transform the construction industry. However, scholars have acknowledged that neither widespread BIM implementation nor the envisaged systemic changes within the sector have taken place. Despite acknowledging that the industry's conditions and embedded contexts shape innovation's diffusion, existing studies have not explored in depth 'how' the context might influence the episode of change when a new technology is introduced and new practices accompanying technology and old practices co-evolve. By adopting activity theory, its concepts of contradictions and multiple layers involving the activity system, in this paper we explore the interaction between situated and existing practices or the 'how' of implementation, i.e., how the activity system is questioned and redefined in the episode of technological change. Drawing on multiple case studies data, our findings demonstrate that situated practices related to the definition of information requirements, the production and the handover of information were re-enacted following institutionalised sociohistorical constructs (e.g. norms, rules, division of labour) at the industry and organisational levels. The findings provide insights regarding inertia in the transformation of the sector as also deriving from re-enactments of sociohistorical constructs that mediate the institutionalisation of situated practices. Our findings reveal re-enactment as part of the transformation process and contribute to calls for more realistic views on BIM implementation.
After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged sta... more After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged state of building facades rapidly, remotely and accurately. A long-term research effort aims to develop applications that can reconstruct 'as-damaged' BIM models of reinforced concrete (RC) framed buildings based on their 'as-built' BIM models and scans of their 'as-damaged' states. This paper focuses on a crucial step: generating an initial 'best-guess' for the new locations of the façade structural members. The output serves as the seed for a recursive process in which the location and damage to each object is refined in turn. Locating the 'as-built' structural members in the 'as-damaged' scan is challenging because each member may have different displacement and damage. An algorithm was developed and tested for the case of reinforced concrete frames with masonry infill walls. It exploits the topology of the frames to map the original structural grid onto the damaged façade. The tests used synthetic datasets prepared from records of two earthquake-damaged buildings. In both cases, the results were sufficiently accurate to allow progress to the following step, assessment of the individual structural members.
Building Information Modelling (BIM) assured a collaborative workflow for the AEC disciplines; ho... more Building Information Modelling (BIM) assured a collaborative workflow for the AEC disciplines; however, the current workflows especially in the building performance disciplines are still sequential, fragmented, and served by diverse software. One of the main reasons for that is the building performance domain has multiple native performance models and data schemas from a wide variety of simulation tools, which leads to incompatible, incomplete, or redundant information in the current performance analysis workflows. Consequently, a different workflow is needed in the building performance modeling discipline. This research focuses on a new paradigm that consists of a holistic ontological framework for building performance modeling with cloud and semantic web technologies, which is founded on a knowledge-graph-driven database management system.
The conventional approach of designing BIM projects requires packaging of building information as... more The conventional approach of designing BIM projects requires packaging of building information as files to exchange designs. This study develops a series of components to implement a previously established Cloud BIM (CBIM) platform that facilitates fileless cloud collaboration across BIM disciplines. A CBIM connector was developed to synchronize design changes from one discipline client to a CBIM server. The server processes the modifications and propagates relevant reference geometries to affected disciplines to assist their designs. The success of the case study demonstrates a fileless approach for multidisciplinary BIM collaboration and validates the practicality and capabilities of the CBIM paradigm.
The potential for automated construction quality inspection, construction progress tracking and p... more The potential for automated construction quality inspection, construction progress tracking and post-earthquake damage assessment drives research in interpretation of remote sensing data and compilation of semantic models of buildings in different states. However, research efforts are often hampered by a lack of full-scale datasets. This is particularly the case for earthquake damage assessment research, where acquisition of scans is restricted by scarcity of access to post-earthquake sites. To solve this problem, we have developed a procedure for compiling digital specimens in both pre-and post-event states and for generating synthetic data equivalent to which would result from laser scanning in the field. The procedure is validated by comparing the physical and synthetic scans of a damaged beam. Interpretation of the beam damage from the synthetic data demonstrates the feasibility of using this procedure to replace physical specimens with digital models for experimentation and for other civil engineering applications.
A novel formula for payment to subcontractors, which shifts some of the risk for reduced producti... more A novel formula for payment to subcontractors, which shifts some of the risk for reduced productivity due to plan instability from the subcontractor to the general contractor, is proposed. The formula requires that a price for capacity be set as well as a price for product, with a single weighting parameter to balance between them. Using a three player game theory based simulation, use of the formula has been shown to lead to resource allocation behaviours that benefit all parties in unstable or average conditions, but has no effect under stable conditions.
For multi-story apartment buildings, the "product" that customers value has two distinct componen... more For multi-story apartment buildings, the "product" that customers value has two distinct components: shared (exterior and shared internal spaces) and private (individual apartments). The basic elements are the same (flooring, plumbing, etc.), and they are installed by the same trades using the same work methods. Yet the shared and private components are fundamentally distinct; the former entails repetitive work packages with stable design and process information, whereas the latter has high variation between products, for which information arrives in an unpredictable fashion as customers make final decisions about interior finishes. Although this dichotomy has been identified in the literature and its deleterious effects studied, construction management has ignored it and attempted to manage both project types within the same production system and by using similar management tools. In this paper, we explicate the shared/private delineation drawing on analogies from manufacturing processes (such the Mass vs. High-Mix, Low-Volume distinction) and discuss appropriate management tactics to address the inherently dual nature of the integrated final product.
The project Building Information Model (BIM), made up of component trade models, can be used to c... more The project Building Information Model (BIM), made up of component trade models, can be used to coordinate and sequence building elements prior to construction. The model should serve as a surrogate for prototyping the actual construction process and can also be used to implement the lean practice of filtering work for constraints prior to assigning work. The term 'constructible BIM element', referring to an element that can be built exactly as it is modeled, is defined to focus on the use of the model for constraint removal and visual planning. Using an in-depth case study, incomplete assignments from Weekly Work Plans were identified and their root causes were mapped onto their associated BIM objects. This spatial analysis makes explicit and begins to quantify the connection between constructability of BIM elements and the variability of work execution in the field. Learning from the underlying patterns, the authors propose process changes for teams to more effectively identify constructability issues in BIM models, and thus leverage the BIM process to improve the reliability of field work planning.
Proceedings of the 31st Annual Conference of the International Group for Lean Construction (IGLC31)
Optimized Cycle-Time Flow (OCF) is a comprehensive lean construction approach to portfolio, proce... more Optimized Cycle-Time Flow (OCF) is a comprehensive lean construction approach to portfolio, process, and operations management of design, demolition, and tool installation projects. It comprises seven principles which teams can implement in sequence to align resources across a portfolio of projects, remove constraints, and plan for continuous uninterrupted execution of each project once it has started. Beginning in 2018, it has been applied to increasingly larger portfolios of projects in an expanding set of Intel facilities, generating consistently reliable results with up to 50% reductions in project cycle-time. A plethora of quantitative data collected through action research over five years indicate that the characteristics of OCF make it more resilient and persistent than many lean construction interventions, overcoming the various barriers to implementation discussed in the literature. The results indicate that OCF principles, vertical integration, leadership, and education make OCF repeatable and scalable. Applying these features to lean construction implementations may help practitioners achieve better results.
Proceedings of the 31st Annual Conference of the International Group for Lean Construction (IGLC31)
PICO is a framework that provides a conceptual guide for production system analysis and design in... more PICO is a framework that provides a conceptual guide for production system analysis and design in the construction industry. It has four key components: Production control mechanism, Information and communication system, Commercial terms, and Organizational structure. Each component is highly interdependent and has a set of detailed parameters and enumerated values. A comprehensive literature review, case studies, and analysis highlighted the knowledge gaps in current production system design frameworks. The PICO framework was originally devised to design a production system suited for short-takt production in residential construction, but it has been developed into a comprehensive mapping tool for the design and analysis of construction production systems in general. The paper shows an application of the framework to a takt system as a case study and an example of its application. The framework expands the current understanding of production systems in construction, offering new insights and a comprehensive approach to designing new production systems.
The data and information of objects in building information modelling (BIM) from different softwa... more The data and information of objects in building information modelling (BIM) from different software are delivered with incomplete data and misclassified objects. This study focuses on classifying mechanical, electrical, and plumbing (MEP) objects based on interdomain topological relationships and geometry conditions through semantic web technologies and semantic enrichment with a rule-based inferencing technique. Four rule sets were developed and run over 32 knowledge graphs of building models with at least 90% accuracy. False positives and negatives arose from non-discrete geometry and topology features of the objects. To address this issue, future work will integrate the proposed method with image recognition.
The building performance domain suffers from inaccurate, incomplete, or repeating information due... more The building performance domain suffers from inaccurate, incomplete, or repeating information due to application-specific data structures, which leads to poor data integrity and interoperability. In particular, no building acoustic ontology with a generalized and integrated data structure has been published. This study aims to create a unified and generalized building acoustic ontology based on reverse engineering over acoustic software applications. The study is a starting point for design of a domain-specific ontology as a knowledge repository by serving the building acoustic performance principles in generalized conceptual modeling and linking semantics and object relations in a building information graph.
Annual Conference of the International Group for Lean Construction, Jul 6, 2020
Production in earthworks projects is a continuous process of strictly sequenced operations perfor... more Production in earthworks projects is a continuous process of strictly sequenced operations performed by heavy machinery on site. The Production Process Evaluation (PPE) index was developed to evaluate these types of processes by quantifying waste in the bottleneck operation. The PPE index is the ratio of the actual production volume to the theoretical maximum production volume, and it is calculated by assessing value adding and nonvalue adding times, actual and theoretical throughput, and shift durations. These are computed using data obtained from machine control systems linked to the roadel information schema, which represents continuous products and processes. The PPE index was implemented on a case study of a water reservoir construction project. The spreading operation was identified as the bottleneck in the process, based on the high levels of inventory waiting for the operation, the high capacity utilization in the operation and the low capacity utilization of the predecessor and successor operations. The PPE index ranged from 45% to 54% during the three weeks of the case study and indicated high levels of waste in the bottleneck and a lack of production management.
Current building design collaboration follows a siloed and sequential workflow, leading to cumber... more Current building design collaboration follows a siloed and sequential workflow, leading to cumbersome manual rework, multiple files and versions, onerous coordination tasks, etc. Designers struggle to meet the demands of modern construction projects in terms of time, cost, quality and sustainability. Interdisciplinary collaboration can be greatly improved through a new paradigm that entails synchronous collaboration with reinvented functions within BIM technologies. To explore this new paradigm, we adopted the design science approach with five steps: (i) literature review, (ii) mockup design, (iii) survey distribution, (iv) focus groups, and (v) data analysis. The results validate the importance of interdomain design change, strongly support the case for the utility of the use case scenarios, and recommend several directions for future research.
Annual Conference of the International Group for Lean Construction, Jun 26, 2023
Production system design, planning and control are limited both by the incomplete situational awa... more Production system design, planning and control are limited both by the incomplete situational awareness of planners and by their inability to predict the range of possible outcomes of their planning and control decisions. With the development of information technologies for monitoring products and processes on construction sites, it is increasingly possible to provide detailed status information describing the as-built products 'as-built' and processes 'asperformed'. This opens the door to applying predictive analytics to provide decision-makers with frequent predictions of the outcomes for a range of changes they might contemplate to the production system design, even during construction. Within the BIM2TWIN project, we are designing and implementing an agent-based simulation engine that is a core component of an Automated Decision Support System. Currently, the simulation can be calibrated to accurately predict the range of likely project durations for a residential construction project. However, certain aspects of the trade crews' performance, particularly with respect to the completion of tasks, appear to differ from the behaviours described by industry experts and encapsulated in the crew agent behaviour tree in the simulation.
After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged sta... more After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged state of building facades rapidly, remotely and accurately. A long-term research effort aims to develop applications that can reconstruct 'as-damaged' BIM models of reinforced concrete (RC) framed buildings based on 'as-built' BIMs and scans of 'asdamaged' states. This paper focuses on a crucial step: generating an initial 'best-guess' for the new locations of the façade structural elements. The result serves as the seed for a recursive process in which the location and damage to each object is refined in turn. Mapping the 'as-built' BIM frame into the 'as-damaged' scan is challenging because each element may have different displacement and damage. The algorithm exploits the topology of RC frames to perform initial mapping of the structural grid onto the damaged facade. The approach was tested on a synthetic dataset prepared from a real earthquake-damaged building. Although successful, it has yet to be tested on other damaged buildings.
Annual Conference of the International Group for Lean Construction, Jul 18, 2018
In the contemporary agenda of airport design, good spatial design is fundamental to properly and ... more In the contemporary agenda of airport design, good spatial design is fundamental to properly and efficiently manage boarding and disembarking processes. It contributes to the Passenger Experience and social sustainability of the terminal itself. This correlates with higher satisfaction levels from the passenger experience. By contrast, current practices of airport design do not properly cope with its requirements and the subsequent operation phase, because the project is not associated with the complete set of stakeholder requirements including the passengers to systematic modelling and management of their experience. The airport terminal is considered a temporary production system, its focus being the transformation of travellers, aimed to maximize the value for passengers, exploiting information management to better accommodate processes and project structuring. In a lean perspective, the terminal is a "flight factory", whose layout is crucial not only for process efficiency but also to achieve higher performance and user satisfaction, the main metrics for quality service evaluation. Considering the multidisciplinary and complex features involved in airport terminal space programming, Lean Design could have important outcomes in the search for project design integration, effective solutions, quality and all-encompassing sustainability. In this paper we discuss a theoretical framework to investigate value delivery in airport terminal design through the integration of lean thinking, constituting the basis for future research on Passenger Experience.
The purpose of the automated, computer-integrated building realization process is to generate, au... more The purpose of the automated, computer-integrated building realization process is to generate, automatically, all the information and the related documents for the design and the construction of a built facility. The paper reviews the concept of the computer controlled realization process and describes the knowledge base of the system employed for this purpose.
Construction Management and Economics, Jul 16, 2020
Building Information Modelling (BIM) has been widely acknowledged as a new paradigm to transform ... more Building Information Modelling (BIM) has been widely acknowledged as a new paradigm to transform the construction industry. However, scholars have acknowledged that neither widespread BIM implementation nor the envisaged systemic changes within the sector have taken place. Despite acknowledging that the industry's conditions and embedded contexts shape innovation's diffusion, existing studies have not explored in depth 'how' the context might influence the episode of change when a new technology is introduced and new practices accompanying technology and old practices co-evolve. By adopting activity theory, its concepts of contradictions and multiple layers involving the activity system, in this paper we explore the interaction between situated and existing practices or the 'how' of implementation, i.e., how the activity system is questioned and redefined in the episode of technological change. Drawing on multiple case studies data, our findings demonstrate that situated practices related to the definition of information requirements, the production and the handover of information were re-enacted following institutionalised sociohistorical constructs (e.g. norms, rules, division of labour) at the industry and organisational levels. The findings provide insights regarding inertia in the transformation of the sector as also deriving from re-enactments of sociohistorical constructs that mediate the institutionalisation of situated practices. Our findings reveal re-enactment as part of the transformation process and contribute to calls for more realistic views on BIM implementation.
After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged sta... more After an earthquake, Terrestrial Laser Scanning (TLS) can capture point clouds of the damaged state of building facades rapidly, remotely and accurately. A long-term research effort aims to develop applications that can reconstruct 'as-damaged' BIM models of reinforced concrete (RC) framed buildings based on their 'as-built' BIM models and scans of their 'as-damaged' states. This paper focuses on a crucial step: generating an initial 'best-guess' for the new locations of the façade structural members. The output serves as the seed for a recursive process in which the location and damage to each object is refined in turn. Locating the 'as-built' structural members in the 'as-damaged' scan is challenging because each member may have different displacement and damage. An algorithm was developed and tested for the case of reinforced concrete frames with masonry infill walls. It exploits the topology of the frames to map the original structural grid onto the damaged façade. The tests used synthetic datasets prepared from records of two earthquake-damaged buildings. In both cases, the results were sufficiently accurate to allow progress to the following step, assessment of the individual structural members.
Building Information Modelling (BIM) assured a collaborative workflow for the AEC disciplines; ho... more Building Information Modelling (BIM) assured a collaborative workflow for the AEC disciplines; however, the current workflows especially in the building performance disciplines are still sequential, fragmented, and served by diverse software. One of the main reasons for that is the building performance domain has multiple native performance models and data schemas from a wide variety of simulation tools, which leads to incompatible, incomplete, or redundant information in the current performance analysis workflows. Consequently, a different workflow is needed in the building performance modeling discipline. This research focuses on a new paradigm that consists of a holistic ontological framework for building performance modeling with cloud and semantic web technologies, which is founded on a knowledge-graph-driven database management system.
The conventional approach of designing BIM projects requires packaging of building information as... more The conventional approach of designing BIM projects requires packaging of building information as files to exchange designs. This study develops a series of components to implement a previously established Cloud BIM (CBIM) platform that facilitates fileless cloud collaboration across BIM disciplines. A CBIM connector was developed to synchronize design changes from one discipline client to a CBIM server. The server processes the modifications and propagates relevant reference geometries to affected disciplines to assist their designs. The success of the case study demonstrates a fileless approach for multidisciplinary BIM collaboration and validates the practicality and capabilities of the CBIM paradigm.
The potential for automated construction quality inspection, construction progress tracking and p... more The potential for automated construction quality inspection, construction progress tracking and post-earthquake damage assessment drives research in interpretation of remote sensing data and compilation of semantic models of buildings in different states. However, research efforts are often hampered by a lack of full-scale datasets. This is particularly the case for earthquake damage assessment research, where acquisition of scans is restricted by scarcity of access to post-earthquake sites. To solve this problem, we have developed a procedure for compiling digital specimens in both pre-and post-event states and for generating synthetic data equivalent to which would result from laser scanning in the field. The procedure is validated by comparing the physical and synthetic scans of a damaged beam. Interpretation of the beam damage from the synthetic data demonstrates the feasibility of using this procedure to replace physical specimens with digital models for experimentation and for other civil engineering applications.
A novel formula for payment to subcontractors, which shifts some of the risk for reduced producti... more A novel formula for payment to subcontractors, which shifts some of the risk for reduced productivity due to plan instability from the subcontractor to the general contractor, is proposed. The formula requires that a price for capacity be set as well as a price for product, with a single weighting parameter to balance between them. Using a three player game theory based simulation, use of the formula has been shown to lead to resource allocation behaviours that benefit all parties in unstable or average conditions, but has no effect under stable conditions.
For multi-story apartment buildings, the "product" that customers value has two distinct componen... more For multi-story apartment buildings, the "product" that customers value has two distinct components: shared (exterior and shared internal spaces) and private (individual apartments). The basic elements are the same (flooring, plumbing, etc.), and they are installed by the same trades using the same work methods. Yet the shared and private components are fundamentally distinct; the former entails repetitive work packages with stable design and process information, whereas the latter has high variation between products, for which information arrives in an unpredictable fashion as customers make final decisions about interior finishes. Although this dichotomy has been identified in the literature and its deleterious effects studied, construction management has ignored it and attempted to manage both project types within the same production system and by using similar management tools. In this paper, we explicate the shared/private delineation drawing on analogies from manufacturing processes (such the Mass vs. High-Mix, Low-Volume distinction) and discuss appropriate management tactics to address the inherently dual nature of the integrated final product.
The project Building Information Model (BIM), made up of component trade models, can be used to c... more The project Building Information Model (BIM), made up of component trade models, can be used to coordinate and sequence building elements prior to construction. The model should serve as a surrogate for prototyping the actual construction process and can also be used to implement the lean practice of filtering work for constraints prior to assigning work. The term 'constructible BIM element', referring to an element that can be built exactly as it is modeled, is defined to focus on the use of the model for constraint removal and visual planning. Using an in-depth case study, incomplete assignments from Weekly Work Plans were identified and their root causes were mapped onto their associated BIM objects. This spatial analysis makes explicit and begins to quantify the connection between constructability of BIM elements and the variability of work execution in the field. Learning from the underlying patterns, the authors propose process changes for teams to more effectively identify constructability issues in BIM models, and thus leverage the BIM process to improve the reliability of field work planning.
Proceedings of the 31st Annual Conference of the International Group for Lean Construction (IGLC31)
Optimized Cycle-Time Flow (OCF) is a comprehensive lean construction approach to portfolio, proce... more Optimized Cycle-Time Flow (OCF) is a comprehensive lean construction approach to portfolio, process, and operations management of design, demolition, and tool installation projects. It comprises seven principles which teams can implement in sequence to align resources across a portfolio of projects, remove constraints, and plan for continuous uninterrupted execution of each project once it has started. Beginning in 2018, it has been applied to increasingly larger portfolios of projects in an expanding set of Intel facilities, generating consistently reliable results with up to 50% reductions in project cycle-time. A plethora of quantitative data collected through action research over five years indicate that the characteristics of OCF make it more resilient and persistent than many lean construction interventions, overcoming the various barriers to implementation discussed in the literature. The results indicate that OCF principles, vertical integration, leadership, and education make OCF repeatable and scalable. Applying these features to lean construction implementations may help practitioners achieve better results.
Proceedings of the 31st Annual Conference of the International Group for Lean Construction (IGLC31)
PICO is a framework that provides a conceptual guide for production system analysis and design in... more PICO is a framework that provides a conceptual guide for production system analysis and design in the construction industry. It has four key components: Production control mechanism, Information and communication system, Commercial terms, and Organizational structure. Each component is highly interdependent and has a set of detailed parameters and enumerated values. A comprehensive literature review, case studies, and analysis highlighted the knowledge gaps in current production system design frameworks. The PICO framework was originally devised to design a production system suited for short-takt production in residential construction, but it has been developed into a comprehensive mapping tool for the design and analysis of construction production systems in general. The paper shows an application of the framework to a takt system as a case study and an example of its application. The framework expands the current understanding of production systems in construction, offering new insights and a comprehensive approach to designing new production systems.
The data and information of objects in building information modelling (BIM) from different softwa... more The data and information of objects in building information modelling (BIM) from different software are delivered with incomplete data and misclassified objects. This study focuses on classifying mechanical, electrical, and plumbing (MEP) objects based on interdomain topological relationships and geometry conditions through semantic web technologies and semantic enrichment with a rule-based inferencing technique. Four rule sets were developed and run over 32 knowledge graphs of building models with at least 90% accuracy. False positives and negatives arose from non-discrete geometry and topology features of the objects. To address this issue, future work will integrate the proposed method with image recognition.
The building performance domain suffers from inaccurate, incomplete, or repeating information due... more The building performance domain suffers from inaccurate, incomplete, or repeating information due to application-specific data structures, which leads to poor data integrity and interoperability. In particular, no building acoustic ontology with a generalized and integrated data structure has been published. This study aims to create a unified and generalized building acoustic ontology based on reverse engineering over acoustic software applications. The study is a starting point for design of a domain-specific ontology as a knowledge repository by serving the building acoustic performance principles in generalized conceptual modeling and linking semantics and object relations in a building information graph.
Think20 (T20) Italy 2021 - Task Force 7: Infrastructure Investment and Financing, 2021
Twenty-first century infrastructure needs to respond to changing demographics, becoming climate n... more Twenty-first century infrastructure needs to respond to changing demographics, becoming climate neutral, resilient and economically affordable, while remaining a driver for development and shared prosperity. However, the infrastructure sector remains one of the least innovative and digitalised, plagued by delays, cost overruns and benefit shortfalls (Cantarelli et al. 2008; Flyvbjerg, 2007; Flyvbjerg et al., 2003; Flyvbjerg et al., 2004). The root cause is the prevailing fragmentation of the infrastructure sector (Fellows and Liu, 2012). To help overcome these challenges, integration of the value chain is needed. This could be achieved through a use-case-based creation of federated ecosystems connecting open and trusted data spaces and advanced services applied to infrastructure projects. Such digital platforms enable full-lifecycle participation and responsible governance guided by a shared infrastructure vision. Digital federation enables secure and sovereign data exchange and thus collaboration across the silos within the infrastructure sector and between industries as well as within and between countries. Such an approach to infrastructure technology policy would not rely on technological solutionism but proposes the development of open and trusted data alliances. Federated data spaces provide access to the emerging data economy, especially for SMEs, and can foster the innovation of new digital services. Such responsible digital governance can help make the infrastructure sector more resilient, efficient and aligned with the realisation of ambitious decarbonisation and environmental protection targets. The European Union and the United States have already developed architectures for sovereign and secure data exchange
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