style="text-align: left;">This paperpresents the results of an experimental and analytical study of the flexural response of concrete box beams prestressed with carbon fiber reinforced polymer (CFRP) tendons Diversified Composites Inc. (DCI) for three highway bridge models. Each bridge model comprises two precast concrete box beams pretensioned using DCI tendons. In one of the bridge models, the box beams were also prestressed using 12 unbonded, DCI post-tensioning tendons. in the second bridge model, the box beams were not provided with post-tensioning tendons. The third bridge model comprised box beams provided with 12 unbonded tendons without any force. This study consisted of predicting parameters such as transfer lengths of DCI tendons, ultimate loads, deflections, post-tensioning forces, strains, and energy ratios. This paperaisopresents a comparison of experimental and analytical results. It was observed that the measured transfer lengths of DCI tendons ranged from 25 to 32 times the nominal tendon diameter. The bridge model comprising box beams prestressed using both pretensioning and unbonded post-tensioning tendons resulted in higher load capacity and lower ductility compared with the other two bridge models. The close agreement between experimental and analytical values signifies the accuracy of a strain-controlled approach in analyzing CFRP box beam bridge models. >References style="text-align: left;">1. ACT Committee 440, 1996, State-of-the-Art Report on Fiber Reinforced Plastic (FRP) Reinforcement for Concrete Structures (ACT 440R-96), American Concrete Institute, Farmington Hills, MI, 65 pp. style="text-align: left;">2. Hindi, A., MacGregor, R., Kreger, M. E., and Breen, J. E., 1995, target="_blank" title="a€?Enhancing Strength and Ductility of Post-tensioned Segmental Box Girder Bridges,a€?" href="http://dx.doi.org/10.14359/1472 ">a€?Enhancing Strength and Ductility of Post-tensioned Segmental Box Girder Bridges,a€? ACI Structural Journal, V. 92, No. 1, January-February, pp. 33-44. style="text-align: left;">3. Taly, N., 1998, Design of Modern Highway Bridges, McGraw Hill Companies Inc., New York, NY, pp. 382-487. style="text-align: left;">4. Kato, T. and Hayashida, N., 1993, Flexural Characteristics of Prestressed Concrete Beams with CFRP Tendons, (ACI SP-138), American Concrete Institute, Farmington Hills, MI, pp. 41-440. 5. Mutsuyoshi, H. and Machida, A., 1993, Behavior of Prestressed Concrete Beams Using FRP as External Cable (ACI SP-138), American Concrete Institute, Farmington Hills, MI, 1993, pp. 401-418. style="text-align: left;">6. Grace, N. F. and Sayed, G. A., 1997, a€?Behavior of Externally/Internally Prestressed Composite Bridge System,a€? Third International Symposium on Non-Metallic (FRP) Reinforcement for Concrete Structures, V. 2, Sapporo, Japan, pp. 671-678. style="text-align: left;">7. Grace, N. F., Enomoto, T., Abdel-Sayed, G., Yagi, K., and Collavino, L., 2003, target="_blank" title="a€?Experimental Study and Analysis of a Full-Scale CFRP/CFCC Double-Tee Bridge Beam,a€? " href="http://dx.doi.org/10.15554/pcij.07012003.120.139 ">a€?Experimental Study and Analysis of a Full-Scale CFRP/CFCC Double-Tee Bridge Beam,a€? PCI Journal, V. 48, No. 4, July-August, pp. 120-139. style="text-align: left;">8. Maissen, A. and De Semet, C. A. M., August 1995, a€?Comparison of Concrete Beams Prestressed with Carbon Fiber- Reinforced Plastic and Steel Strands,a€? Non-Metallic (FRP) Reinforcement for Concrete Structures, Second International RILEM Symposium (FRPRCS), Ghent, Belgium, pp. 430-439. style="text-align: left;">9. Naaman,A. E. and Jeong, S. M., August 1995, a€?Structural Ductility of Concrete Beams Prestressed with FRP Tendons,a€? Non-Metallic (FRP) Reinforcement for Concrete Structures, Second International RILEM Symposium (FRPRCS), Ghent, Belgium, pp. 379-386.
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