Title:
Bi-Surface Shear Test for Evaluating Bond between Existing and New Concrete
Author(s):
A. Momayez, A. A. Ramezanianpour, H. Rajaie, and M. R. Ehsani
Publication:
Materials Journal
Volume:
101
Issue:
2
Appears on pages(s):
99-106
Keywords:
bond strength; concrete; repair; shear strength; silica fume; test
DOI:
10.14359/13045
Date:
3/1/2004
Abstract:
While bond tests have been developed for several specific applications, there is no consensus among practitioners for evaluating the bond strength under a shear state of stress that is commonly encountered in structures. This investigation was aimed at presenting a new shear test method for evaluating the bond between repair materials and concrete substrate. This method uses a 150 mm cube where the repair material constitutes 1/3 of the specimen volume. Three point loads are applied such that they produce a state of shear stress on the repaired interface. The test variables included specimen size, maximum aggregate size of repair materials, type of repair material, interface roughness, and age at loading. This test method is easy to carry out on both laboratory and field samples. The bond strength was improved with surface roughness, silica fume content, and age at testing. Larger specimens resulted in lower bond strength. Bi-surface shear is a reliable test for determining bond between existing concrete and repair materials.