Project Title: Development and Testing of Crashworthy Ipe Bridge Rails

Bridge and guard rails are extraordinarily common along roads and highways around the world (Ritter et al. 1999, Wacker and Smith 2001). Even the most low-traveled rural bridge likely has rails installed for safety, and of course interstate highway systems have rails that can vary from concrete along bridges to cable lines across medians and metal railings at shoulders. Various types of railing have been studied for decades, and excellent design guidelines exist for nearly every class of railing. Typical types of railing can include formed steel in the shape of convex shell structures, simple solid wood timbers spliced with lap joints, hollow steel or other metal tubing that can be arrayed in either its strong or weak direction to adjust the stiffness at impact, glu-lam beams attached to solid wood posts, and cable “rails”. Representative configurations for these types of railings are shown below in Figure 1. Clearly, there are massive differences in cost and effectiveness between various barriers, and there are only limited numbers of studies that have attempted to compare the various types of railing (Shankar et al. 2000, Plaxico et al. 2000). In this study, we will complete a thorough review of all previously published studies of guardrails (including both performance and cost) throughout the United States along with collecting data on guard rail events in Colorado. But th