Patrick B. Dillon and Gerald A. Dalrymple
Patrick B. Dillon, Project Engineer II, WDP & Associates Consulting Engineers, Inc., Charlottesville, VA, United States, pdillon@wdpa.com
Gerald A. Dalrymple, Principal, WDP & Associates Consulting Engineers, Inc., Manassas, VA, United States, adalrymple@wdpa.com
ABSTRACT
Adhered Masonry Veneer (AMV) has increased in popularity in recent years and is becoming commonplace both in residential and commercial construction as an alternative to more conventional stone veneer systems. However, unlike stone veneer, AMV material characteristics and installation methods can vary considerably based on aesthetic considerations, manufacturer’s installation requirements, and local installer means and methods. The variability of this application, coupled with detailing and integration challenges on the part of designers and specifiers, has led to an increase in AMV adhesion failures and durability problems. Loss of adhesion has been observed to be one of the principal causes of failure of adhered masonry veneers. For over two decades, the TMS 402 prescriptive provisions have included requirements for the bond between the units and backing to develop a minimum shear strength of 345 kPa (50 psi). However, until recently there was no standardized test method that could be used for verifying the shear bond strength of installed AMV units in the field. This paper presents a case study from an investigation in which in-field shear bond strength testing of AMV was performed for both investigation of an AMV failure and pre-construction quality control. The investigation employed a test methodology similar to that recently published in ASTM C1823. The field testing identified several insights regarding AMV installation and performance and highlights the importance of performing shear bond testing of AMV installations.
KEYWORDS: adhered masonry veneer, adhered masonry stone veneer, ASTM C1823, field testing, shear bond testing, thin brick
