Adhesive Applied Roofing System Resistance Evaluation and its Quantification

Adhesive Applied Roofing System (AARS) is a new generation of built-up roof, gaining popularity in the North American low-slope roofing market. All components of AARS are integrated using adhesives. Wind flow creates suction over a low-slope roof, which exerts uplift forces on the roof system. The components of AARS are subjected to the combined action of tensile and shearing forces due to the dynamic wind uplift action. As part of a research project, to quantify the wind performance of AARS, three different test methods, namely, pullout (to simulate the tensile force), peel (to simulate the shear force), and wind uplift tests were developed by Current (2009), Wu (2008) and Murty (2010), respectively. Three test methods have been submitted to standard development organizations for industrial applications.;To help the industrial partners, a portable tester was designed such that it can be used for pullout and peel tests in the field. The design specifications of the portable tester were extracted from the requirements of the pullout and peel test methods based on the laboratory tests. The tester was manufactured by SAI Design Inc. First, the functionality of the portable tester was verified by testing the resistance of roofing fasteners. To further validate the portable tester, more than two hundred AARS specimens of different configurations were constructed and tested by using both the portable tester and Instron machine. The test results and observed failure modes were compared. The data confirmed that the portable tester is a useful and valid equipment in performing both the pullout and peel tests. The device can be used in the field for the evaluation of system response under wind action. Thus it will be useful in quantifying the impact of environmental conditions on the AARS specimens and to examine the effects of component substitutions.;The present study proposes a correlation among these three different test methods, namely, "Higher resistance in both peel and pullout tests will result in the same or higher wind uplift resistance". The present proposal is being verified through experimental study. For four different scenarios, two set of samples were constructed by varying only one component between the samples. For each sample, more than eight specimens were tested in all three test methods. Data from peel, pullout and wind uplift test methods were compared and it successfully verified the present hypothesis. It is concluded that the test results obtained from the small-scale pullout and peel experiments can be used to predict the effectiveness of full-scale system behaviour. This finding is very useful to assess the wind uplift performance of AARS that are already in service. It is also applicable to the situation where the component substitution for AARS is needed at the construction site.