MPC
Research Projects (2005-06)

Project Title

Workshop on Experimental Wood-Concrete Highway Bridge Construction

University

Colorado State University

Project Investigators

Dr. Richard Gutkowski
Colorado State University
(970)491-8291
gutkowsk@engr.colostate.edu

Dr. Jeno Balogh
Colorado State University
(303)257-7278
jbalogh@engr.colostate.edu

External Project Contact

N/A

Project Objective

The objective of this workshop is technology transfer on experimental roadway bridge construction involving innovative composite wood-concrete technology being developed in ongoing research.

Project Abstract

Deteriorating wood bridge decks are usually completely replaced without consideration of a possible retrofit. This is likely due to a lack of low cost methods to strengthen such decks. One approach to strengthening a wood bridge deck is to add a concrete deck layer and interconnect it to the wood deck. Prior MPC projects at CSU showed this to be successful using a notched shear key/anchor detail tested in the laboratory under static loads. The concept of a single span application of a composite wood-concrete deck-only bridge has evolved and is also being studied in the laboratory at CSU. The application is for bridges of 30 ft span or less. Construction of an actual experimental bridge is needed as proof of concept under actual service conditions. Via international cooperation with other researchers, the CSU researchers are involved in advising on wood-concrete construction in Brazil and Portugal. A workshop is to be planned and conducted to share this evolving technology with local and county jurisdictions in Colorado.

Task Descriptions

CSU researchers are cooperating with INPA-National Institute for Amazonia Research in Manaus, Brazil in the anticipated construction of an experimental wood-concrete bridge. This invitation occurred as a result of a visiting scientist from INPA who was active on the past MPC project work during a 2-year visit to CSU. INPA is planning to construct a bridge in Bosque da Clencia ecological park in Manaus and monitor its performance under extreme climate and extraneous environmental conditions. Laboratory load tests have been conducted at INPA on preliminary test specimens. CSU is advising on the technical work in the laboratory and field construction, acquire and provide on loan the instrumentation needed for the data collection and independently reviewing and assessing the outcomes of the studies.

CSU researchers have initiated cooperating with researchers at the Department of Civil Engineering, the University of Coimbra, Portugal. The Foundation for Portuguese-American Development sponsored a visit to that university by Dr. Gutkowski in May 2004, for that purpose. An experimental (15 m span) composite wood-concrete roadway bridge (different from the CSU concept) was being developed for implementation in the field. Since that time, the bridge was completed. Dr. Gutkowski visited Coimbra in May 2005 to tour the bridge site. Plans were made for joint research in long term creep of the interlayer connections used by CSU in its research and a possible short span second roadway bridge in Portugal using the CSU concept.

The workshop about wood-concrete roadway bridge technology will be conducted at CSU for local and county transportation engineers responsible for road bridge construction in Colorado. A visit to observe CSU's related ongoing laboratory research projects will be included. A TLN teleconference-based seminar will be conducted as part of the activities, to reach other states in the region. The researchers in Portugal and Brazil have been invited to participate with CSU researchers in describing the various technologies, and are interested and developing needed travel funds. The aim of the workshop is to identify receptive parties to follow up concerning possible future joint field research projects.

Milestones, Dates

Starting Date: July 1, 2005
Ending Date: June 30, 2006

Yearly and Total Budget

$12,520

Student Involvement

One graduate research assistant and one undergraduate student

Relationship to Other Research Projects

This is technology transfer and fostering of applications related to outcomes of past and on-going MPC research projects of the subject matter of innovative composite wood-concrete bridge construction.

Technology Transfer Activities

This is embedded in the workshop itself as detailed in the task description.

Potential Benefits of the Project

Rural communities have many sub-20 foot roadway bridges in their jurisdictions. Many provide vehicle passage over streams, irrigation ditches, etc. Sub-20 foot bridges are not included as bridges in official FHWA National Bridge Inventory. However, a past MPC project shows that there are a great number of them. The study also showed that as they are "unofficial" bridges (not eligible for federal aid) repair and replacement funds are extremely limited or non-existent. The mixed material technology is an ideal replacement method as it is low cost and readily constructed by ordinary labor force when abutments already exist. Thus local and county bridge owners would have an option for addressing the sub-20' bridge needs via a low cost, in-house solution. For medium spans the labor is increased but still possible with unskilled to semi-skilled labor force. This ease of construction helps reduce costs relative to allocating scarce federal aid dollars available on a competitive basis.

TRB Keywords

Bridges, composite, wood-concrete, workshop