ENG  Vol.7 No.7 , July 2015
Connection between Concrete Layers with Different Strengths
Abstract: As part of a research intending to develop steel-concrete hybrid girder using ultra high performance concrete with compressive strength of 80 MPa, this study conducts loading test on this girder to investigate the methods for its composition with a slab using 30 MPa-concrete and the corresponding interfacial behavior. Prior to the loading test, the design formula of the Eurocode for the shear resistance developed in concrete-to-concrete interface is examined for the interface between concrete layers of different strengths. The effect of the surface roughness on the shear resistance is examined using this formula and finite element analysis to verify the applicability of the formula. Based upon the results, loading test is conducted on girder specimens to evaluate the actual behavior with respect to the interfacial surface condition. The test results reveal that the specimen with rough interface could not develop perfectly composite behavior and experienced adhesive failure. In case of simultaneous action of flexure and shear, it appears that conservative design should be applied without consideration of the interfacial condition when determining the arrangement of shear reinforcement.
Cite this paper: Kang, J. , Park, J. , Jung, W. and Keum, M. (2015) Connection between Concrete Layers with Different Strengths. Engineering, 7, 365-372. doi: 10.4236/eng.2015.77032.

[1]   Hanson, N.W. (1960) Precast-Prestressed Concrete Bridges 2. Horizontal Shear Connections. Journal of the PCA Research and Development Laboratories, 2, 38-58.

[2]   Birkeland, H.W. and Birkeland, P.W. (1996) Connections in Precast Concrete Construction. Journal of the ACI, 63, 345-368.

[3]   Mattock, A.H. and Hawkins, N.M. (1972) Shear Transfer in Reinforced Concrete—Recent Research. PCI Journal, 17, 55-75.

[4]   Walraven, J.C. and Reinhardt, H.W. (1981) Theory and Experiments on the Mechanical Behaviour of Cracks in Plain and Reinforced Concrete Subjected to Shear Loading. Heron, 26.

[5]   Loov, R.E. and Patnaik, A.K. (1994) Horizontal Shear Strength of Composite Concrete Beams with Rough Interface. PCI Journal, 39, 48-69.

[6]   Júlio, E., Branco, F. and Silva, V. (2004) Concrete-to-Concrete Bond Strength. Influence of the Roughness of the Substrate Surface. Construction and Building Materials, 18, 675-681.

[7]   Júlio, E. and Santos, P. (2010) Comparison of Methods for Texture Assessment of Concrete Surfaces. ACI Materials Journal, 107, 433-440.

[8]   European Committee for Standardization (2002) EN 1992-1-1 Eurocode 2: Design of Concrete Structures—Part I: General Rules and Rules for Buildings.

[9]   CEB-FIP (2010) Fib Model Code for Concrete Structures.