Title:
Concrete Q&A: Tensile Bond Strength of Concrete
Author(s):
Scott Tarr
Publication:
Concrete International
Volume:
40
Issue:
7
Appears on pages(s):
71-72
Keywords:
DOI:
10.14359/51710847
Date:
7/1/2018
Abstract:
My company installed a bonded topping on an existing slab. The project specifications required a compressive strength of 4000 psi (27.6 MPa) for the topping concrete. Although our concrete met that requirement, we were directed to remove and replace the topping. The owner’s explanation: The concrete topping was inadequate because pull-off tests failed to achieve 400 psi (2.8 MPa), which is 10% of the compressive strength. Does ACI provide any recommendation on acceptable bond strength for toppings/overlays?
Related References:
1. Harrington, D., and Fick, G., “Guide to Concrete Overlays: Sustainable Solutions for Resurfacing and Rehabilitating Existing Pavements,” Third Edition, ACPA Publication TB021.03P, American Concrete Pavement Association, Washington, DC, 2014, p. 106.
2. Felt, E.J., “Resurfacing and Patching Concrete Pavement with Bonded Concrete,” Proceedings of the Thirty-Fifth Annual Meeting of the Highway Research Board, V. 35, 1956, pp. 444-469.
3. ACI Committee 503, “Use of Epoxy Compounds with Concrete (ACI 503R-93, Reapproved 2008),” American Concrete Institute, Farmington Hills, MI, 1993, 28 pp.
4. Silfwerbrand, J., “Shear Bond Strength in Repaired Concrete Structures,” Materials and Structures, V. 36, No. 6, July 2003, pp. 419-424.
5. ACI Committee 503, “Standard Specification for Repairing Concrete with Epoxy Mortars (ACI 503.4-92, Reapproved 2003)” American Concrete Institute, Farmington Hills, MI, 1992, 5 pp.