Constructability of Full-Depth Precast Deck on a Steel Girder Bridge with Injection Channel Connection

In this study, the constructability of a full-depth precast deck installation on a steel girder bridge with injection channel connection was evaluated. This type of girder has been developed to avoid the overlap between the shear studs and the bridge deck, which is a major issue causing delays in modular construction. First, the optimal dimensions and lifting method for the deck were determined through finite element analysis. Subsequently, the constructability of deck installation on the bridge was evaluated with various radii of curvature using building information modeling (BIM). For the efficient use of BIM, algorithm-based models for the girder and deck were developed to change their shapes easily.

Evaluation and Load Rating of a Steel Girder In-Span Hinge Connection

Continuous steel plate girder bridges often use intermediate expansion joints located at in-span hinges to divide the superstructure into individual units with shorter expansion lengths. One common type of in-span hinge is often termed a “shiplap joint.” This type of joint is located away from piers near the moment inflection point of the span, maximizing girder efficiency. It consists of a cantilevered portion of the superstructure supporting a suspended portion of the latter on bearings placed on dapped portions of the steel plate girders. Few references are available for the evaluation and load rating of shiplap in-span hinges used in steel girder bridges. In this study, the strength and stability of a typical shiplap hinge connection is evaluated using two methodologies: a 3D finite element model including a detailed mesh of the connection; and a proposed simplified methodology based on design equations. Load ratings of the connections based on these methodologies are compared. The proposed approach allows for a conservative assessment of the hinge without the need for a detailed finite element model.

Generating Labour Cost Budget for a Construction-Oriented Fabrication Facility: Simulation-based Resource Scheduling Approach

A novel labour-hour budgeting methodology is proposed by integrating productivity concepts in project scheduling and budgeting to enhance the accuracy of labour cost budgeting for planning labour-intensive projects. The proposed methodology applies discrete event simulation approach to represent crew formation, labour resource utilization and labour resource flowing between consecutive activities, which allows for quantitatively characterizing the impact of labour semi-productive time on labour cost budgeting as a time-dependent variable. Simulation-based assessment of variations in crew sizes and labour allocations is conducive to reducing semi-productive time and thus enhancing the cost performance of the whole project. The proposed methodology is then applied in a real-world case study for planning steel girder fabrication projects in construction of highway bridges. Not limited to budgeting for labour resources in construction-oriented fabrication facility, the research contributions are also significant to other construction planning settings where limited resources are shared and utilized among different activities.