1 Copyright © 2017 by ASME Proceedings of the ASME 2017 International Mechanical Engineering Congress and Exposition IMECE2017 November 3-9, 2017, Tampa, Florida, USA IMECE2017-71588 POLE PLACEMENT NEAR THE MIDWEST GUARDRAIL SYSTEM Mojdeh A. Pajouh Midwest Roadside Safety Facility University of Nebraska-Lincoln Lincoln, NE, USA John D. Reid Mechanical & Materials Engineering University of Nebraska-Lincoln Lincoln, NE, USA Robert W. Bielenberg Midwest Roadside Safety Facility University of Nebraska-Lincoln Lincoln, NE, USA Jennifer D. Schmidt Midwest Roadside Safety Facility University of Nebraska-Lincoln Lincoln, NE, USA Ronald K. Faller Midwest Roadside Safety Facility University of Nebraska-Lincoln Lincoln, NE, USA ABSTRACT Poles are regularly placed along highways and are used to support signs, lights and electrical lines. The Midwest Guardrail System (MGS) is a standard W-beam guardrail system used throughout the United States to redirect vehicles that leave the roadway away from dangerous roadside obstacles, like ravines, water hazards, and bridge piers. Placing poles near a guardrail may affect its ability to safely contain and redirect vehicles. The compatibility of poles placed in the proximity of the MGS is studied using nonlinear finite element analysis. Computer simulations were conducted with vehicles impacting the MGS with varying lateral pole offsets between the back of the system and the front face of the pole, and varying longitudinal pole location from being placed directly behind a post to directly behind the unsupported rail half-way between posts. Results show that poles placed within 16 inches behind the MGS may cause concern in regard to acceptable crash test performance for guardrail systems. Additional simulations and full-scale crash testing is required before guidelines can be recommended. INTRODUCTION Poles are regularly placed along highways and are used to support signs, lights and electrical lines [1]. The Midwest Guardrail System (MGS) is a standard W-beam guardrail system used throughout the United States to redirect vehicles that leave the roadway away from dangerous roadside obstacles, like ravines, water hazards, and bridge piers [2]. Placing poles near a guardrail may affect its ability to safely contain and redirect vehicles. The compatibility of poles placed in the proximity of the MGS is studied using the nonlinear finite element analysis software LS-DYNA® [3]. An example of an Illinois Tollway luminaire pole next to an MGS is shown in Figure 1. Figure 1. Illinois Tollway Luminaire Pole Behind an MGS An MGS placed along the roadway is depicted in Figure 2. In the majority of installations there is no curb. For the standard MGS, current Illinois Tollway practice specifies a 28” minimum barrier clearance distance.