MPC Research Reports
Report Details

Title:	Composite Repair of Timber Structures
Authors:	D. W. Radford, M.L. Peterson, and D. VanGoethem
University:	Colorado State University
Publication Date:	Jun 2000
Report #:	MPC-00-112
Project #:	MPC-161
TRID #:	00796266
Keywords:	composite materials, fiberglass, laminated wood, repairing, rods, shear properties, spikes, stiffness, strength of materials, timber construction, transverse reinforcement, transverse stiffeners, wooden bridges

Abstract

The present research suggests a new approach to the use of composite materials technology for repair of timber structural members. Due to the small aspect ratio of the typical railroad bridge span timbers, stiffness degradation can be related to decrease in the beam's shear performance. To rejuvenate the beam, the proposed approach focuses on overcoming the loss of shear properties by inserting fiberglass rods from the bottom to the top of the beam, through the areas of damage. The concept includes the injection of an adhesive during the process of insertion, which not only bonds the reinforcing rods in-place, but also fills adjacent cracks. To support this rejuvenation approach, scale beam testing was carried out with a variety of reinforcement cases being evaluated. The overall result is extremely positive, with test beams showing strong recovery of flexural properties through the addition of fiberglass shear spikes. Thus, these results suggest that further, full-scale testing should be undertaken to fully develop the repair approach.