SangHyeok Han

An Automated Biomechanical Simulation Approach to Ergonomic Job Analysis for Workplace Design

AbstractWork-related musculoskeletal disorders (WMSDs) are reported to be the most common category of nonfatal occupational injuries that result in days away from work and are also a leading cause of temporary and permanent disability. One of the most effective approaches to preventing WMSDs is to evaluate ergonomics considerations early in the design and construction planning stage before the worker encounters the unsafe conditions. However, a lack of tools for identifying potential ergonomic risks in a proposed workplace design has led to difficulties in integrating safety and health into workplace design practice. In an effort to address this issue, this study explores a motion data-driven framework for ergonomic analysis that automates and visualizes the evaluation process in a virtual workplace. This is accomplished by coupling the ergonomic analysis with three-dimensional (3D) virtual visualization of the work environment. The proposed approach uses motion data from the 3D model of the jobsite to ev...

Algorithm for Mobile Crane Walking Path Planning in Congested Industrial Plants

AbstractOn-site construction of industrial projects relies heavily on large mobile cranes for the lifting of prefabricated modules, which over the years have become heavier and more voluminous. Industrial construction sites are frequently congested, a condition that reduces the area where cranes can freely maneuver. As a result, in some cases mobile cranes may not have sufficient clearance to perform the lifts and thus need to pick and walk with loads to a point from which the modules can ultimately be set in their resting positions. Since this type of crane operation presents higher risks of failure or accident in comparison to the traditional scenario, in which the location of the crane does not change for the duration of the lifting, a detailed analysis of these operations is paramount to ensure safety and efficiency. Paradoxically, many practitioners still rely on their best judgment for crane walking planning, which in the case of highly congested and complex construction sites is likely to lead to i...

Integrated Building Information Model to Identify Possible Crane Instability caused by Strong Winds

Large scale construction projects often involve the lifting of heavy equipment. With increases in equipment size, lifting operations create new challenges in crane selection. In terms of safety, stability is one of the most important factors to consider when selecting cranes. Although practitioners often apply simulation tools to select appropriate cranes, the effect of wind on crane stability is not yet considered in the selection process. Considering that cranes are among the most expensive types of equipment, contractors need to plan the crane operations properly to improve safety and reduce cost and time. This paper presents a methodology to implement the safe operation of cranes by identifying possible crane instability caused by strong winds using Building Information Modeling (BIM), a tool which prepares smart designs to integrate and coordinate cross-disciplinary designs, the construction process, and facility management decisions. A methodology is proposed to integrate wind effects on crane operations which can be considered a major step in developing future BIM. Through a case study involving multiple heavy lifts in an industrial project, the benefits of the proposed methodology are identified.

Simulation of mobile crane operations in 3D space

A 3D model allows users to visualize the construction process during a given period of the schedule. This paper presents a methodology to aid practitioners in preparing lift studies with crane selection, positioning, and lift optimization using a 3D space. The 3D visualization helps to identify collision free paths and optimize lifting activities based on optimal crane paths with cycle time and speed of each crane activity from simulation models in Simphony. The proposed methodology provides to help lifting engineering and project manager select the best possible crane. A case study-based approach is utilized to illustrate the proposed methodology. The case study involves construction of a four story, sixty-eight unit building for older adults in Westlock, AB, Canada. The 3D visualization model was provided for the construction team more than two months before the scheduled day of lifting, which assisted the contractor in selecting the optimum crane and successfully completing all lifts (thirty modules, 25 tons each) in just two working days.

3D Visualization-Based Ergonomic Risk Assessment and Work Modification Framework and Its Validation for a Lifting Task

AbstractThe construction manufacturing industry in North America has a disproportionately high number of lost-time injuries because of the high physical demand of the labor-intensive tasks it invol...

3D-Based Crane Evaluation System for Mobile Crane Operation Selection on Modular-Based Heavy Construction Sites

AbstractModular-based heavy industrial projects, which involve a large number of lifts on congested and/or dynamic site layouts, require not only the design and selection of efficient mobile crane ...

A VR Model of Ergonomics and Productivity Assessment in Panelized Construction Production Line

Factory based (modular and panelized) building methods have been applied to a high proportion of construction projects due to their reduced waste, limited environmental impact, and decreased cost and construction times. Redesigning the production process, facility layout, and material handling process can thus improve productivity and reduce costs for manufacturers. Virtual Reality (VR) is increasingly being used to investigate the best methods for balancing the flow of construction activities and optimizing resources to prevent costly on-site errors. This tool can be applied in planning and designing module systems in manufacturing production lines to promote healthy, safe, and productive working conditions by reducing workers’ fatigue and injuries, and their associated costs. This paper identifies and quantifies work-related ergonomic hazards from residential construction floor panel framing activities, using the VR model of the construction process to replace onsite observation and an ergonomic assessment based on ErgoCheck, a comprehensive ergonomic rating and assessment framework. The VR model uses an internal timer for productivity (cycle time) assessment. The impact of the ergonomic interventions on work productivity is thus assessed and the results show the potential of ergonomic interventions in improving production line productivity through a reduction in idle and cycle time.

Noise exposure assessment of a modular construction manufacturing factory

The National Institute for Occupational Safety and Health (NIOSH) has laid down specific regulations to prevent harmful impacts of noise on workers. However, due to the lack of awareness of irreparable noise damages, the potential of the auditory and non-auditory diseases is increasing. In the modular construction manufacturing, which is increasingly applied as a construction method, construction workers are substantially exposed to high-noise levels. In order to provide a healthier workplace, assessment of the noise exposure is necessary while in this industry has not been fully studied yet. Therefore, this paper presents noise exposure assessment of a modular construction factory. After investigating patterns of the tasks, task-based method (TBM) was applied as a measurement strategy. K-means clustering was used to determine the noise level of each task to calculate the noise exposure levels in different locations of the factory. The results of this paper can provide a useful guideline to manage the noise efficiently in the modular construction sector.

Integrated Visualization and Simulation for LiftingOperations of Modules under Congested Environment

Modular-based heavy construction projects are recognized as faster, safer, and more efficient than traditional those completed through on-site construction methods. The successful completion of these projects relies on an efficient material handling system, especially when mobile cranes are utilized to satisfy heavy lift requirements. However, engineers are faced with the challenge of planning the lifting operations of heavy modules within congested areas. Currently, mobile crane analysis is implemented manually, but requires timeconsuming data input resulting in an increase of errors and a lack of proper crane productivity performance analysis; this complicates the planning process. To overcome these limitations, the research presented in this paper proposes to integrate visualization and simulation, in an approach known as post-3D visualization simulation, in order to plan collision-free crane lifts by eliminating potential errors in 3D visualization and to predict crane productivity performance in simulations. This proposed system will contribute to the successful completion of construction projects with high productivity and site-error reduction by selecting the best crane operation that includes various crane lifts. An actual industrial project which has a number of constraints, including space limitations, different types of site layouts, and various crane lifts, is used to validate the proposed framework.

Automation for Mobile Crane Motion Planning in Industrial Projects

Mobile cranes are used to lift heavy modules in industrial projects. These heavy modules are often prefabricated and each project consists of a large number of lifts (e.g., a typical industrial project may have between 150 and 1000 modules to be lifted). To ensure the safety and efficiency of these lifting activities, crane motion planning is needed. However, in practice, most of the heavy lift studies are, at best, performed semiautomatically and still require significant manual work. In addition to being inefficient, this approach is also characterized by a high error rate, especially in the context of congested construction sites, not to mention its slow response to changes in work order or project scope. For instance, if a module is delayed, the crane motion planning may need to be redesigned (at least partially) since the configuration of the obstacles on the construction site no longer conforms to what had been assumed in the original planning. This paper thus proposes a generic model for mobile crane motion planning that can be implemented in industrial projects. The proposed approach considers the typical site constraints and performs automatic planning for the entire site. An industrial project with more than 100 modules is selected for validation of the proposed method. 3D visualization is also developed to demonstrate the lifts in a 3D Studio Max environment.