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Title:Investigation of Cross Timber Bridge Decks as a Sustainable Solution for Repair of Deficient Rural Wood Bridges
Authors:Anirudh Kode, John W. van de Lindt, and M. Omar Amini
University:Colorado State University
Publication Date:May 2021
Report #:MPC-21-437
Project #:MPC-487
TRID #:01778838
Keywords:bridge decks, diaphragms (engineering), earthquake resistant design, laminated wood, load tests



Cross Laminated Timber (CLT) has only recently garnered attention as a new construction material in the United States. Despite being introduced in Europe nearly 20 years ago, CLT is still not used widely in North America. One primarily reason is because CLT is not yet recognized as a structural system for seismically active regions of the country. One sub-assembly that has not been fully investigated are horizontal diaphragms for floors, roofs, or bridge decks. This report aims to test a single large-scale CLT cantilever diaphragm subjected to a simulated seismic load. Data were collected and the behavior of the diaphragm documented to help begin to reduce this dearth of CLT data in the United States. These data will also assist in refining CLT diaphragm design procedures that have recently been developed.

Ten CLT panels were used to build the diaphragm, which was set up as a cantilever beam according to ASTM specifications. A 110-kip actuator was used to apply a concentrated load at one end of the diaphragm while a steel base serving as a fixed boundary condition was at the other end. The CUREE test protocol with a reference displacement of 75.6 mm (3 inches) was applied to the floor diaphragm specimen, which included a number of string potentiometers to collect displacement data. The diaphragm behaved in a predictable manner and the connectors initially failed in tension first even with a chord designed per the National Design Specification for wood. Then the CLT panels separated, resulting in a total failure. This dataset will be made available to those working on CLT diaphragm provisions for refinement of ongoing revisions.

How to Cite

Kode, Anirudh, John W. van de Lindt, and M. Omar Amini. Investigation of Cross Timber Bridge Decks as a Sustainable Solution for Repair of Deficient Rural Wood Bridges, MPC-21-437. North Dakota State University - Upper Great Plains Transportation Institute, Fargo: Mountain-Plains Consortium, 2021.

NDSU Dept 2880P.O. Box 6050Fargo, ND 58108-6050