Development of Iowa Dot Combination Bridge Separation Barrier with Bicycle Railing

Authors

Chaz M. Ginger, University of Nebraska-LincolnFollow

First Advisor

John D. Reid

Date of this Version

8-2018

Citation

Ginger, C.G., Development of Iowa DOT Combination Bridge Separation Barrier with Bicycle Railing, Thesis to University of Nebraska-Lincoln Graduate Studies, July 23, 2018.

Comments

A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Mechanical Engineering and Applied Mechanics, Under the Supervision of Professor John D. Reid. Lincoln, Nebraska : August, 2018.

Copyright (c) 2018 Chaz M. Ginger

Abstract

The Iowa Department of Transportation typically builds separation barriers between vehicle and pedestrian/bicycle facilities when sidewalks or trails are present on vehicular bridges. Currently, Iowa DOT employs a combination bridge rail that utilizes a concrete parapet that previously had been successfully evaluated to National Cooperative Highway Research Program (NCHRP) Report 350 Test Level 4 (TL-4) criteria for these situations. While the parapet had been successfully evaluated, the combination bridge rail system as a whole had not been evaluated to any crash test standards. Iowa DOT desired that researchers at Midwest Roadside Safety Facility (MwRSF) design and test a combination bridge separation barrier to current Manual for Assessing Safety Hardware (MASH) TL-2 standards to use in place of their current, untested system.

During this effort, previous combination rails, low-height vertical parapets, and zone of intrusion (ZOI) studies were reviewed to provide guidance on system design. A simulation effort was also performed to aid in height selection of the parapet, as well as placement of the attached bicycle rail to reduce the amount of negative vehicle-to-rail interaction with the system. Using the information gathered during the review of previous systems and simulation effort, a full system design was produced. It was then recommended that the proposed system be evaluated to MASH test designation 2-11 in order to assess the system’s performance during a vehicle impact scenario.

Advisor: John D. Reid