Project 3.21: GBeam Bridge Girder Pultrusion: Section Design and Optimization

GBeam Bridge Girder Pultrusion: Section Design and Optimization


Project Summary

The GBeam girder system, recently developed by the University of Maine (Dagher et al. 2019; Davids et al. 2022a; Davids et al. 2022b), holds significant promise for widespread application in conventional, slab-on-girder bridges. Its successful initial implementation is driven by enhanced durability, low maintenance, lightweight, and ease of erection. However, girder fabrication time and cost are currently high due to the use of labor-intensive vacuum infusion, and widespread adoption of the CT girder hinges on the ability to make girders faster. The proposed research tackles this issue by exploring the feasibility of commercial girder manufacturing via pultrusion. Inextricably linked with pultrusion is optimization of the girder fiber architecture and cross-section to ensure compatibility with the pultrusion process while retaining adequate capacity with efficient material utilization. This project is short-term in nature and designed to provide the information needed to complete the design of a pultrusion die for girder fabrication. Upon completion of this project, AIT Bridges must make a go/no-go decision on designing and purchasing a girder pultrusion die, a significant capital expenditure. While we are reasonably confident a section amenable to pultrusion will result from this research, success is not guaranteed and girder pultrusion cannot proceed without a pultrusion die. If AIT Bridges does purchase a die and successfully pultrudes GBeams, and follow-on project will be initiated to experimentally assess and verify the behavior of the pultruded section.

Principal Investigator

Dr. Bill Davids


University of maine

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Office of the Assistant Secretary for Research and Technology, University Transportation Centers Program, Department of Transportation, University of Maine

Implementation of Research Outcomes:

This project is in its initial research phase. Implementation of research outcomes will be reported upon completion of the research outputs.

Impacts and Benefits of Implementation:

This project is in its research phase. Impacts and benefits of the research will be reported after the implementation phase.

Printable Info Sheet

September 2022 Quarterly Progress Report