Non-Destructive Evaluation and Numerical Modeling of Unrated Installed Crash Barriers

US Transportation Collection2022PDFTech ReportPokhrel, AsheshSorensen, Andrew D.Utah State University. Department of Civil and Environmental EngineeringUtah. Department of Transportation. Research and Innovation DivisionUnited States. Department of Transportation. Federal Highway AdministrationUtah. Dept. of Transportation. Division of ResearchUnited StatesBarriers (Roads)Nondestructive testsNumerical analysisTest proceduresValidationMidwest Guardrail System (MGS)UDOT 42 in (1067 mm) Constant Slope BarrierUDOT 54 in (1372 mm) Constant Slope BarrierManual for Assessing Safety Hardware (MASH)Finite element models (FEM)LS-DYNAUT-21.3020-8397Final Report Oct 2019 to June 2022Finite element models (FEM) for Midwest Guardrail System (MGS) and constant UDOT slope 42-in and 54-in cast-in-place (CIP) fixed barriers are created in LS-DYNA. The FEM of a Chevrolet Silverado pickup truck is used to perform a Test Level 3 (TL-3) crash simulation for the MGS. FEMs of a Ford 800 single unit truck (SUT) and a tractor-trailer are used, respectively, to perform TL-4 and TL-5 crash simulations for the 42-in and 54-in barriers. In the first phase of this report, these three barrier types are examined for their ability to contain and redirect the vehicles successfully using the commercial FEM software package LS-DYNA. The simulation results gave satisfactory results for the MGS in terms of structural adequacy (ability to contain and redirect) and for the 42-in and 54-in (1067 mm and 1372 mm) barriers in terms of structural adequacy and occupant risk factors. The flexible MGS barrier is able to reduce the speed of the crashing vehicle and redirect it while sustaining large deflection in the barrier section. In the case of rigid TL-4 and TL-5 barriers the vehicle is diverted into the same lane without overriding the barrier although permanent damage to the barrier and vehicles is observed. It is concluded that all three barrier types are safe and fulfill their functionality according to the Federal Highway Administration (FHWA) Manual for Assessing Safety Hardware (MASH) standards when analyzed using LS-DYNA.140