详情

Crashworthy Foundations for Soil-Embedded Roadside Safety Hardware

项目名称：	Crashworthy Foundations for Soil-Embedded Roadside Safety Hardware
摘要：	Run-off-road crashes with soil-embedded safety hardware, such as luminaire poles and guardrail posts, are not well-understood for soil conditions other than MASH strong soil. The selection of an appropriate foundation depends on several factors including support structure type, structural stiffness, transmitted loads, soil properties, soil-structure interaction, groundwater conditions, and depth to bedrock. This project will primarily focus on the specific application of luminaire pole foundations. Current luminaire pole foundation designs commonly implemented by state DOTs rely on guidance from the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications and AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals. These AASHTO guidelines are based on Broms’ method (1964) which relies on static analysis. Designs typically follow static load-based methods (i.e., Brom’s method), which has led to overdesigned foundations. Furthermore, there are no guidelines for design of crashworthy foundations embedded in soils other than medium to dense, dry soil. AASHTO guidelines do not address crashworthy foundation design for sites with “weak” soil (i.e., silts, soft clay, peat, organic soil) and/or soil with high moisture content. Geographic soil variability as well as seasonal variations in groundwater conditions across the country call for research to enable cost-effective and safe soil-embedded safety hardware for an extended array of specific site conditions (i.e., weak, and/or saturated soil) considering more realistic and accurate dynamic loads rather than static loads. The objectives of this research project are to (1) evaluate adequacy of state DOTs’ existing practices, (2) enhance existing modeling methods for soil behavior during vehicle impact events, and (3) develop preliminary guidelines for luminaire foundation depth accounting for soft and/or saturated soil. This project will complement a current project at Midwest Roadside Safety Facility (MwRSF) which aims to develop design guidance for crashworthy luminaire pole foundations in the state of Alaska, satisfying Manual for Assessing Safety Hardware (MASH) safety criteria.
状态：	Active
资金：	351788
资助组织：	Office of the Assistant Secretary for Research and Technology
执行机构：	University of Nebraska, Lincoln
开始时间：	20200901
预计完成日期：	20220228
主题领域：	Design；Geotechnology；Highways；Safety and Human Factors；Terminals and Facilities