MPC
Research Projects (2009-10)

Identifying Number

MPC-325

Project Title

Fatigue Testing of Wood-Concrete Composite Beams

University

Colorado State University

Project Investigators

Jeno Balogh
Rebecca Atadero
E-mail: rebecca.atadero@colostate.edu

Description of the Project Abstract

Wood-concrete composite beams are novel structural members that in the past decade become subject of extensive research world-wide due to their attractive properties such as sustainability and insulation. At the current stage they are employed mostly in building structures (office and residential), although a few pilot bridge applications were also made. The problem with using these novel members in bridges is that the fatigue behavior of the composite member is not known. This research addresses that issue, by attempting to establish the S-N curve for wood-concrete beams with shear-key anchor detail for short-span bridges based on high-cycle repeated loading experimental tests. Hardly any test of such a type has been performed in the past. The obtained S-N curve could be proposed for the future revisions of the Timber-Concrete Composite Design Codes.

Project Objectives

The objective of this project is to establish the S-N (stress-number of cycles) curve for wood-concrete composite beams with shear-key anchor connection detail.

In preceding successful work, the concept of wood-concrete composite members was developed into beam configurations. Beam specimens (representative of a full bridge cross section) were laboratory load tested to failure under ramp loading. Composite action achieved was extremely high, approximately 95% degree of efficiency. The proposed study experimentally investigates the behavior (including the efficiency and fatigue) of such beams under high-cycle repeated loads as they occur in bridge applications.

Project Approach/Methods

The prior work consisted of wood-concrete composite beam testing for short-term load, sustained load, and low-cycle repeated load. Prior research results are reported in MPC Reports cited below. This research will use similar specimens built from dimensional lumber joined together by wood screws and a top layer of fiber reinforced concrete. The layers are interconnected at notches that are cut into the wood layer. The static failure load will be experimentally determined. Then, high-cycle repeated load testing will be applied to the other specimens. MTS equipment will be used in testing.

The anticipated tasks in the study are:

Task 1 - Using the results of prior MPC research, configure and build 12 wood-concrete composite beams. Test for pertinent material properties of the wood and concrete used.

Task 2 - Load test two of the specimens under static ramp loading to failure. Define the maximum repeated load as 60% of the average failure load.

Task 3 - Apply high-cycle repeated loading until failure test to five sets of two beams each. The minimum repeated load to maximum repeated load ratio for each set will be set to 0.1, 0.2, 0.3, 0.4 and 0.5 respectively. Compare the performance of the five sets and approximate the S-N curve.

Task 4 - Develop an MPC research report on the findings.

MPC Critical Issues Addressed by the Research: This work addresses USDOT Strategic Goal -Infrastructure Management (and Environmental Stewardship): (1) Improved Infrastructure Design, (2) Infrastructure Longevity, and (3) Infrastructure that Minimizes Environmental Impacts.

MPC Critical Issues Addressed by the Research

#15 - Improved Infrastructure Design
#16 - Infrastructure Longevity
#17 - Environmental Impacts of Infrastructure

Contributions/Potential Applications of Research

Much of rural America has low tax base communities dependent on agricultural economies and related freight and shipping industry. State and federal parks face tight budgets for daily operations and maintenance overall and especially for road and bridge maintenance and construction. Developing low cost, easily constructed bridge systems for short to medium span situations on secondary roads is helpful in these situations. Examples of recently constructed layered w/c bridges exist in Switzerland, and Portugal. These successful overseas examples lend credibility to the above concept as being practically plausible, feasible and economical. However, without knowing the fatigue behavior of this system only applications with very low traffic are possible. This research will contribute to the knowledge in this area, and potentially will enable the use of wood-concrete composite bridges in higher traffic conditions (a pilot higher-traffic application is envisioned in Portugal).

Technology Transfer Activities

An S-N curve will be obtained for wood-concrete composite beams described. A written MPC report and TLN teleconference seminar are planned for dissemination of the results. The results will support a potential future pilot field bridge construction which is envisioned (with presently undetermined timing) after this project concludes, in Portugal in cooperation with the Portuguese researchers.

Time Duration

July 1, 2009 through June 30, 2010

Total Project Cost

$20,720.00

MPC Funds Requested

$18,569.00

TRB Keywords

Bridge, Composite, Fatigue, Wood-Concrete, Repeated Loading

References

• Gutkowski, R.M., W. Thompson, K. Brown, P. Etournaud, A. Shigidi and J. Natterer, 1999. "Laboratory Tests of Composite Wood - Concrete Beam and Deck Specimens." Proceedings of "1999 RILEM Symposium on Timber Engineering". Stockholm, Sweden.
• Gutkowski, R.M., E. Koike, P. Etournaud, and J. Natterer, 1999. "Laboratory Tests of Composite Wood - Concrete Beam & Deck Specimens." Proceedings of "STRUCTURAL FAULTS + REPAIR" - 99, 8th International Conference and Exhibition, London, England.
• Gutkowski, R.M., J. Balogh, J. Natterer, K. Brown, E. Koike, and P. Etournaud. 2000. "Laboratory Tests of Composite Wood - Concrete Beam and Floor Specimens". Proceedings of the World Conference on Timber Engineering - 2000, Whistler Resort, B.C., Canada; Department of Civil Engineering, Department of Wood Science; School of Architecture, University of British Columbia, Vancouver, Canada.
• Gutkowski, R.M., J. Balogh. 2001. "Refined Modeling of Composite Wood-Concrete Beam and Deck Specimens," Proceedings, 9th International Conference and Exhibition in Structural Faults and Repair - 2001, ASCE, London, UK.
• Gutkowski, R. M., Brown, K., Etournaud, P. and Thompson, W. 2001. "Shear Key for Strengthening Bridges," MPC Report No. 01-126, Mountain Plains Consortium, North Dakota State University, Fargo, N.D.
• Balogh, J. Wieligmann, M., Gutkowski, R., P. Haller. 2002. Stress-Strain Behavior of Connections for Partially Composite Wood-Concrete Floors and Deck Systems, Proceedings- 2nd Material Specialty Conference of the Canadian Society of Civil Engineering, Montreal, Quebec, Canada.
• Gutkowski, R., Balogh, J. Rogers, C., SaRibeiro, R. 2002. Laboratory Tests of Deep Composite Wood-Concrete Beam and Deck Specimens, Proceedings- 4th Structural Specialty Conference of the Canadian Society of Civil Engineering, Montreal, Quebec, Canada
• Balogh, J., Gutkowski. R. M., Wieligmann, M. and Haller, P. 2002. Mechanics behavior of dowel connectors for partially composite wood-concrete beam. Proceedings, The 7th World Conference on Timber Engineering, Selangor, Malaysia, Mara University of Technology, Vol 4.
• Gutkowski, R., Balogh, J., Rogers, C, and Shigidi, A.M.T. 2002. Load test of composite wood-concrete deep beam specimen. Proceedings, The 7th World Conference on Timber Engineering, Selangor, Malaysia, Mara University of Technology, Vol 3.
• Ceccotti, A., Fragiacomo, M. and Gutkowski, R. 2002. Design of timber-concrete composite structures according to EC5 - 2002 version. Proceedings of 35th Meeting of Working Commission W18 - Timber Structures, Kyoto, Japan. International Council for Research and Innovation in Building and Construction, Lerhstuhl fur Ingeniieurholzbau und Baukonstructionen, Universitat Karlsruhe, Germany.
• R. Gutkowski, J. Balogh, M. Wieligmann, C. Rogers and P. Haller. 2003. Analysis and Testing of Composite Wood-Concrete Floor/Deck Systems. Proceedings of CMEM 2003, Eleventh International Conference on Computational Methods and Experimental Measurements, Halkidiki, Greece, WIT Press, Wessex Institute of Technology, UK.
• Fast, R.S. 2003. "Durability Studies of Layered Wood-Concrete Composite Connections and Beams," Structural Research Report No. 84, Colorado State University.
• Gutkowski, R.M., K. Brown, A. Shigidi and J. Natterer, 2003. Investigation of Notched Composite Wood-Concrete Connections. Journal of Structural Engineering, ASCE, Reston, VA, 130 (10) pp 1553-1561.
• C. Rogers, R. Gutkowski, and J. Balogh. 2004. "Load Tests of Large Wood-Concrete Beams", MPC Report No. 04-165, Mountain Plains Consortium, North Dakota State University, Fargo, N.D.
• Fragiacomo, M., Gutkowski, R.M., Balogh, J., and Fast, R.S. 2006. "Long-term behavior of wood-concrete composite beams with notched connection detail." 9th World Conference on Timber Engineering WCTE 2006, Portland (U.S.A.), August 6-10, 8 pp., CD.
• R.M. Gutkowski, M. Fragiacomo, J. Balogh, and R. Fast. (2006) Time-Dependent Performance of Notched Wood-Concrete Composite Beams, ," Proceedings, 11th International Conference and Exhibition in Structural Faults and Repair -2006, Edinburgh, Scotland.
• Fragiacomo, M., Gutkowski, R.M., Balogh, J., and Fast, R.S. 2007. "Long-term behavior of wood-concrete composite floor/deck systems with shear key connection detail." Journal of Structural Engineering, ASCE, Vol. 133, No. 9, pp. 1307-1315.
• Gutkowski, R. M., K. Brown, A. Shigidi, and J. Natterer, 2007. Laboratory Tests of Composite Wood-Concrete Beams, Construction and Building MATERIALS, Elsevier Ltd., Edinburgh, Scotland.
• Balogh, J., Fragiacomo, M., Gutkowski, R. M. and R. S. Fast, R. S. 2007, "Influences of Repeated and Sustained Loading on the Performance of Layered Wood-Concrete Composite Beams", Journal of Structural Engineering. ASCE.
• M. LeBorgne and R. Gutkowski. 2008. Load Testing of Wood-Concrete Beams Incorporating Recycled Utility Poles. MPC Report No. 08-197. Mountain-Plains Consortium, North Dakota State University, Fargo. ND.
• LeBorgne M. and Gutkowski, Richard, M., Accepted for Publication. "Effects of various admixtures and shear keys in wood-concrete composite beams". Construction and Building Materials, Elsevier Publications, Edinburgh, Scotland.