Measuring of bond: a comparative experimental research

In the framework of European test methods for masonry a simple test method for bond has to be established. The described research, carried out at Eindhoven University of Technology, tried to contribute to the development of such a test method. In this perspective, the research was focused on bond wrench testing. To investigate the outcome of the bond wrench test a comparative research was carried out using five different test methods in combination with two types of masonry. In total 407 bond tests were performed, using the five different test methods. It was concluded that the bond wrench can be used as a means to predict bond. Under labo-ratory conditions it gave the same or a lower CV as with wallette testing. Taking into account statistical considerations concerning the number of joints tested in flexure, the bond wrench is able to predict the flexural strength parallel to the bed joint as reliable as the flexural test on wallettes.