An Experimental and Statistical Analysis of the Flexural Bond Strength of Masonry Walls

Abstract

This paper describes an experimental program where full sized clay brick unreinforced masonry walls were constructed by masons with different levels of skills. The flexural bond strength of each joint in each wall was obtained using the bond wrench test. This provided extensive data for a statistical analysis to assess the degree of spatial correlation of that property. The analysis also included a comparison between the flexural bond strength of joints within the walls and prisms. The study recommended that flexural bond strengths between joints are statistically independent and that the commonly used prisms may not represent adequately the wall.

Key Words:

• Masonry
• flexural bond strength
• statistics
• correlation
• prisms

Additional information

Notes on contributors

M R S Corrêa

Márcio Corrêa is associate professor in the Department of Structural Engineering, Engineering School of São Carlos, University of São Paulo (USP), Brazil, where he started to lecture and do research in 1980. Graduated in 1979, he obtained his Master degree in 1983, Doctorate degree in 1991 and his Habilitation in 2003. His research subjects are tall buildings, masonry, reinforced concrete, and numerical and experimental analysis. He has supervised 18 MSc and 6 PhD projects on civil and structural engineering. He has stayed as a visiting academic in the University of Edinburgh, Scotland, in 1997 and in the University of Newcastle, Australia, in 2001. Márcio is author or co-author of 145 papers (journals and proceedings), one book (Design of structural masonry buildings) and two chapters of books. He has participated in the joint committees to revise the Concrete and Masonry Brazilian Standards, being the coordinator of the Brazilian Clay Masonry Code — Design. He has also worked was a consultant engineer developing the structural design of a number of concrete and masonry buildings. Márcio is also editor in chief of the Brazilian Structural Journal CEE.

M J Masia

Mark Masia is a Senior Lecturer in the School of Engineering at the University of Newcastle. He graduated with his Bachelor Degree in Civil Engineering from the same university in 1994. After working as a consulting structural engineer for two years he returned to the University of Newcastle to undertake postgraduate studies. He received his PhD in Structural Engineering in 2000. He then worked as a Postdoctoral Research Fellow at the University of Calgary, Canada, during 2000 and 2001, before returning to the University of Newcastle in September 2001. Mark’s primary research interests lie in the area of the structural behaviour of masonry structures. The research includes both unreinforced and fibre-reinforced polymer retrofitted masonry.

M G Stewart

Prof Mark G. Stewart is an ARC Australian Professorial Fellow and Director of the Centre for Infrastructure Performance and Reliability at the University of Newcastle in Australia. He is co-author of Terror, Security, and Money: Balancing the Risks, Benefits, and Costs of Homeland Security (Oxford University Press, 2011), Probabilistic Risk Assessment of Engineering Systems (Chapman & Hall, 1997), as well as more than 300 technical papers and reports. He has more than 25 years of experience in probabilistic risk and vulnerability assessment of infrastructure and security systems that are subject to manmade and natural hazards. Mark has significant expertise in time and spatial dependent reliability analysis of new and existing deteriorating structures, such as bridges and buildings. This has utility for assessing the safety and service-life prediction of new and existing structures. Since 2004, Mark has received extensive ARC support to develop probabilistic risk-modelling techniques for infrastructure subject to military and terrorist explosive blasts and cost-benefit assessments of counter-terrorism protective measures for critical infrastructure. In collaboration with the CSIRO, Mark is also assessing the impact of climate change on damage and safety risks to infrastructure, and assessing the cost-effectiveness of engineering adaptation strategies. He is also a leading investigator with the reliability-based calibration of the Australian Masonry and Concrete Codes.

L M Heffler

Leesa Heffler (BE (Civil), MPhil) completed her Masters by research at the University of Newcastle in 2009. Her thesis was titled Variability of Unit Flexural Bond Strength and its Effect on Strength in Clay Brick Unreinforced Masonry Walls Subject to Vertical Bending.