In recent years, there have been significant advances in modeling technology for object-oriented ... more In recent years, there have been significant advances in modeling technology for object-oriented building products. However, the building models are still lacking of providing construction-specific spatial information required for construction planning. Consequently, construction planners visually analyze building product models and derive geometric characteristics such as bounded spaces and exterior perimeter to develop detailed construction plans. Such a process presents fragmented information flows, from building product information to construction planning, that rely on subjective decisions of construction planners. In order to overcome these drawbacks, this research proposes a geometric reasoning system that analyzes geometric information in building designs, derives the construction-specific spatial information, and uses the information to assist in construction planning. The scope of presented work includes detecting work packages formed by faces during construction, such as large work faces and bounded spaces, and using information in the work packages directly to support planning of selected indoor construction activities. The main features of the proposed system named Construction Spatial Information Reasoner (CSIR) include a set of relationship acquisition algorithms, building component relationship data structure , and interpretation of the relationship to support detailed construction activity planning. The relationship acquisition algorithms identify adjacency between building components that is stored in the relational data structure. Then, acquired adjacency relationships are transformed into a set of graphs that represent work packages. To implement the proposed approach, CSIR utilized a commercially-available Building Information Modeling (BIM) platform and the algorithms were imbedded to the BIM platform. For validation, CSIR was tested on a real commercial building. For interior ceiling grid installation activities , CSIR successfully detected existing work packages and analyzed the spatial characteristics impact-ing construction productivity. The major contribution of the presented research would be to enable a realistic analysis of building geometric condition that is not possible in current BIM and a seamless information flow from building product information to construction process plans. These can potentially reduce current manual and error-prone construction planning processes. Limitations and future research suggestions are also presented.
A construction schedule must satisfy multiple project objectives that often conflict with each ot... more A construction schedule must satisfy multiple project objectives that often conflict with each other. While several earlier approaches attempted to generate optimal schedules in terms of several criteria, most of their optimization processes were segmented into multiple steps. Owing to such a lack of simultaneous optimization, limited alternative solutions could be searched and some trade-offs between goals could not be identified. This paper presents an optimization approach that enables a simultaneous search for an optimal construction schedule in terms of three objectives: minimization of construction duration, cost, and resource fluctuation. A multiobjective optimization (MOO) approach was adopted to generate scheduling solutions considering all those objectives. To enable a simultaneous optimization, we propose a new data structure that can compute the performances of solutions in terms of all the objectives at the same time. A Niched Pareto Genetic Algorithm (NPGA) is modified to facilitate the optimization procedure. Then the proposed optimization approach is implemented in an existing case study. The result indicates that the proposed approach has the capability to explore and generate a greater range of solutions compared to existing models. Trade-offs between all three objectives are identified, limitations and further research needs are discussed.
Computing in Civil and Building Engineering (2014), 2014
ABSTRACT Sixty-five percent (65%) of US workers in the construction industry work on scaffolding.... more ABSTRACT Sixty-five percent (65%) of US workers in the construction industry work on scaffolding. Of these workers 4,500 are injured and 50 die every year due to scaffold-related accidents. Proper safety management, such as scaffolding safety inspections, can support hazard mitigation and prevention. This paper shares the results of a study of the levels of safety risk at each stage of the scaffolding project life cycle for building a masonry wall and how these risks and related mitigation suggestions can be applied to Building Information Models (BIM). Safety is integrated with 4-dimensional (4D) BIM by linking the scaffolding safety risks and mitigations with the project schedule. The 4D BIM can be used as a tool for the safety management to monitor and diminish the safety hazards associated with scaffolding work. Four different stages of research were conducted to determine the safety risks and then implement the mitigations into BIM: (1) Determine the activities associated with working on scaffolding; (2) Collect data from industry professionals about the likelihood and severity of safety hazards at each stage of the scaffolding project life cycle; (3) Establish the safety risks using the collected data and a standardized algorithm; and (4) Incorporate the safety risks into BIM and provide mitigation recommendations. As a result, the 4D BIM can be used throughout the project planning and construction progress to inform the safety management of activities associated with the scaffolding that have high safety risks and to assist safety management in implementing preventative measures according to given mitigation recommendations.
Architectural Engineering and Design Management, 2011
Architects, designers and engineers involved in a sustainable design project often require inform... more Architects, designers and engineers involved in a sustainable design project often require information and tools beyond energy simulation software. They look for tools to support their decisions and to assess the risk involved in decision making. This research presents a ...
In recent years, there have been significant advances in modeling technology for object-oriented ... more In recent years, there have been significant advances in modeling technology for object-oriented building products. However, the building models are still lacking of providing construction-specific spatial information required for construction planning. Consequently, construction planners visually analyze building product models and derive geometric characteristics such as bounded spaces and exterior perimeter to develop detailed construction plans. Such a process presents fragmented information flows, from building product information to construction planning, that rely on subjective decisions of construction planners. In order to overcome these drawbacks, this research proposes a geometric reasoning system that analyzes geometric information in building designs, derives the construction-specific spatial information, and uses the information to assist in construction planning. The scope of presented work includes detecting work packages formed by faces during construction, such as large work faces and bounded spaces, and using information in the work packages directly to support planning of selected indoor construction activities. The main features of the proposed system named Construction Spatial Information Reasoner (CSIR) include a set of relationship acquisition algorithms, building component relationship data structure , and interpretation of the relationship to support detailed construction activity planning. The relationship acquisition algorithms identify adjacency between building components that is stored in the relational data structure. Then, acquired adjacency relationships are transformed into a set of graphs that represent work packages. To implement the proposed approach, CSIR utilized a commercially-available Building Information Modeling (BIM) platform and the algorithms were imbedded to the BIM platform. For validation, CSIR was tested on a real commercial building. For interior ceiling grid installation activities , CSIR successfully detected existing work packages and analyzed the spatial characteristics impact-ing construction productivity. The major contribution of the presented research would be to enable a realistic analysis of building geometric condition that is not possible in current BIM and a seamless information flow from building product information to construction process plans. These can potentially reduce current manual and error-prone construction planning processes. Limitations and future research suggestions are also presented.
A construction schedule must satisfy multiple project objectives that often conflict with each ot... more A construction schedule must satisfy multiple project objectives that often conflict with each other. While several earlier approaches attempted to generate optimal schedules in terms of several criteria, most of their optimization processes were segmented into multiple steps. Owing to such a lack of simultaneous optimization, limited alternative solutions could be searched and some trade-offs between goals could not be identified. This paper presents an optimization approach that enables a simultaneous search for an optimal construction schedule in terms of three objectives: minimization of construction duration, cost, and resource fluctuation. A multiobjective optimization (MOO) approach was adopted to generate scheduling solutions considering all those objectives. To enable a simultaneous optimization, we propose a new data structure that can compute the performances of solutions in terms of all the objectives at the same time. A Niched Pareto Genetic Algorithm (NPGA) is modified to facilitate the optimization procedure. Then the proposed optimization approach is implemented in an existing case study. The result indicates that the proposed approach has the capability to explore and generate a greater range of solutions compared to existing models. Trade-offs between all three objectives are identified, limitations and further research needs are discussed.
Computing in Civil and Building Engineering (2014), 2014
ABSTRACT Sixty-five percent (65%) of US workers in the construction industry work on scaffolding.... more ABSTRACT Sixty-five percent (65%) of US workers in the construction industry work on scaffolding. Of these workers 4,500 are injured and 50 die every year due to scaffold-related accidents. Proper safety management, such as scaffolding safety inspections, can support hazard mitigation and prevention. This paper shares the results of a study of the levels of safety risk at each stage of the scaffolding project life cycle for building a masonry wall and how these risks and related mitigation suggestions can be applied to Building Information Models (BIM). Safety is integrated with 4-dimensional (4D) BIM by linking the scaffolding safety risks and mitigations with the project schedule. The 4D BIM can be used as a tool for the safety management to monitor and diminish the safety hazards associated with scaffolding work. Four different stages of research were conducted to determine the safety risks and then implement the mitigations into BIM: (1) Determine the activities associated with working on scaffolding; (2) Collect data from industry professionals about the likelihood and severity of safety hazards at each stage of the scaffolding project life cycle; (3) Establish the safety risks using the collected data and a standardized algorithm; and (4) Incorporate the safety risks into BIM and provide mitigation recommendations. As a result, the 4D BIM can be used throughout the project planning and construction progress to inform the safety management of activities associated with the scaffolding that have high safety risks and to assist safety management in implementing preventative measures according to given mitigation recommendations.
Architectural Engineering and Design Management, 2011
Architects, designers and engineers involved in a sustainable design project often require inform... more Architects, designers and engineers involved in a sustainable design project often require information and tools beyond energy simulation software. They look for tools to support their decisions and to assess the risk involved in decision making. This research presents a ...
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Papers by Kyungki Kim