Selection of the most effective pavement surfacing strategy for the Glenwood cross laminated timber parking garage

Abstract

The use of cross-laminated timber (CLT) is becoming increasingly common in large scale construction projects as a sustainable alternative. This study assesses the effectiveness of several overlay surfaces which are to be installed on top of floor slabs in a proposed CLT parking garage structure. Overlay surfaces are necessary to protect the CLT from moisture and vehicle loadings within the parking garage. First, finite element modeling was performed to determine stress, strain, and deformation distributions and factors for use in the laboratory tests. Then, three overlay systems were evaluated using laboratory tests (at the stress-strain levels identified by FE modeling) where cracking resistance, interlayer bond strength and rutting (flow number) were the main parameters used to quantify the performance of each overlay strategy. One of the three overlay systems evaluated consisted of a flexible polyurethane membrane applied directly to a CLT panel. The other two overlay systems consisted of dual-layered sheet membranes applied to a CLT panel and then paved over with a modified asphalt pavement. Based on the laboratory test results, a strategy with the asphalt and sheet membrane layers on top of the CLT layer was selected to be the best option due to significant reduction in stress-strain distribution achieved when compared to the other strategies.