Cheng Tzu Thomas HsuWonsiri PunuraiYongxin JiaHaitao BianNew Jersey Institute of TechnologyMahidol University2018-08-202018-08-202006-05-01Journal of Testing and Evaluation. Vol.34, No.3 (2006), 158-166009039732-s2.0-33845254323https://repository.li.mahidol.ac.th/handle/123456789/23386This paper explores the direct shear behavior between carbon fiber-reinforced polymer (CFRP) laminates and concrete. To study the push-off strength and slip relationship of externally bonded strengthening system, a new test setup is proposed herein. In this research, a total of 27 specimens are tested. The test variables include the maximum compressive strength of concrete, from 4000 to 12000 psi. With this test setup, it has been found to be able to investigate the direct shear condition between the CFRP laminates and concrete. Based on the present test results, empirical formulas to account for the push-off strength and slip relationship of various concrete compressive strengths are developed. This relationship enables further understanding of the transfer mechanism between the CFRP laminates and concrete. Also, the effect of salt water on the ultimate direct shear strength of the CFRP strengthening system is discussed. Copyright © 2006 by ASTM International.Mahidol UniversityMaterials ScienceArticleSCOPUS