Degradation of Sealed Joints Installed on Panels of an ALC-Clad Building

Outline of Investigation

An outline of the investigation of sealed joints installed on panels of an ALC- clad building is shown in Table 1. The ALC panels on the building consist of two basic types that may be classified according to the depth of the panel, specifi­cally: (i) The deep ALC panel, for which the depth of the ALC panel cladding is 100 mm, and (ii) the thin ALC panel where the ALC panel depth may be 35, 37, or 50 mm deep. The deep ALC cladding panels are typically used for homes, commercial buildings, or factories having steel frame construction whereas the thin ALC panels are normally used for homes or on low-rise buildings having wood frame construction. In this study, the buildings for which the investiga­tions were completed, all of which were constructed over ten years ago, were inspected in respect to the type of sealants used in the joints, the degree of deg­radation of the sealants, and their respective strength characteristics were sub­sequently determined from laboratory testing. The joint types that had been used for the deep ALC panels or the thin ALC panels are shown in Table 2. As may be seen in Table 2, the deep ALC cladding panels used two-sided working joints whereas the thin ALC panels used three-sided non-working joints. Given that the short side of the joint length along the deep ALC panel deforms to a greater extent than that of a joint on the long side of the panel, it was deter­mined that the representative panel joint would be a two-sided adhesion joint having a width of 10 mm. On the contrary, the joint for the thin ACL panel was considered a three-sided adhesion joint of 7 mm width.