Barre Town, Vermont
The Robbins Nest Covered Bridge is a 57-ft-long, single-span structure that spans over the Jail Branch of the Winooski River. The bridge, constructed in 1962 by Robert Robbins, is 12 ft, 10 inches wide and utilizes Queen Post truss framing. During routine bridge repairs, the contractor uncovered and exposed the lower portions of the bridge trusses, which revealed significant deterioration of a truss chord member. DuBois & King bridge engineers worked with the contractor to provide fast-track field observations, assessments, and in-depth truss analysis, in order to provide engineering and design for truss chord repairs. Repairs included:
Removal of deteriorated section of lower truss chord
Reused truss members that were in good condition
Design of tension splice for chord member interface
Design for total truss capacity of 3 tons (live load)
Principles of the Secretary of the Interior’s Standards of Rehabilitation and the Burlington Charter were applied to truss repair.