A Compact Sled System for Linear Impact, Pole Impact, and Side Impact Testing

Author(s):  
P. Michael Miller ◽  
Todd Nowak ◽  
Walter Macklem
Author(s):  
Shaun Eshraghi ◽  
Michael Carolan ◽  
Benjamin Perlman ◽  
Francisco González

Abstract The U.S. Department of Transportation’s Federal Railroad Administration (FRA) has sponsored a series of full-scale dynamic shell impact tests on railroad tank cars. For each shell impact test a pre-test finite element (FE) model is created to predict the overall force-time or force-displacement histories of the impactor, puncture/non-puncture outcomes of the impacted tank shell, global motions of the tank car, internal pressures within the tank, and the energy absorbed by the tank during the impact. While qualitative comparisons (e.g. the shapes of the indentation) and quantitative comparisons (e.g. peak impact forces) have been made between tests and simulations, there are currently no standards or guidelines on how to compare the simulation results with the test results, or what measurable level of agreement would be an acceptable demonstration of model validation. It is desirable that a framework for model validation, including well-defined criteria for comparison, be developed or adopted if FE analysis is to be used without companion full-scale shell impact testing for future tank car development. One of the challenges to developing model validation criteria and procedures for tank car shell puncture is the number of complex behaviors encountered in this problem, and the variety of approaches that could be used in simulating these behaviors. The FE models used to simulate tank car shell impacts include several complex behaviors, which increase the level of uncertainty in simulation results, including dynamic impacts, non-linear steel material behavior, two-phase (water and air) fluid-structure interaction, and contact between rigid and deformable bodies. Approaches to model validation employed in other areas of transportation where validation procedures have been documented are applied to railroad tank car dynamic shell impact FE simulation results. This work compares and contrasts two model validation programs: Roadside Safety Verification and Validation Program (RSVVP) and Correlation and Analysis Plus (CORA). RSVVP and CORA are used to apply validation metrics and ratings specified by the National Cooperative Highway Research Program Project 22-24 (NCHRP 22-24) and ISO/TS 18571:2014 respectively. The validation methods are applied to recently-completed shell impact tests on two different types of railroad tank cars sponsored by the FRA. Additionally, this paper includes discussion on model validation difficulties unique to dynamic impacts involving puncture.


2004 ◽  
Author(s):  
Suzanne Tylko ◽  
Dainius Dalmotas
Keyword(s):  

2014 ◽  
Author(s):  
Sheryl Janca ◽  
Kurt Shanks ◽  
Janet Brelin-Fornari ◽  
Ravi Tangirala ◽  
Massoud Tavakoli
Keyword(s):  

Author(s):  
Mohammad Atarod

The present study examined trends in occupant dynamics during side impact testing in vehicle models over the past decade. “Moderate-to-high” speed side impacts (delta-V ≥15 km/h) were analyzed. The Insurance Institute for Highway Safety (IIHS) side impact crash data was examined ( N = 126). The test procedure involved a moving deformable barrier (MDB) impacting the sides of stationary vehicles at 50.0 km/h. Instrumented 5th-percentile female SID IIs dummies were positioned in the driver and left rear passenger seats. Occupant head, neck, shoulder, torso, spine, and pelvis/femur responses (times histories, peaks, and time-to-peak values) were evaluated and compared to injury assessment reference values (IARVs). The effects of delta-V, vehicle model year, vehicle body type, and occupant seating position on dynamic responses were examined. The vehicle lateral delta-Vs ranged from 15.9 to 34.5 km/h. The MY2018-2020 demonstrated lower peak dynamics than MY2010-2013, for the driver head acceleration (53.7 ± 11.3 g vs 46.4 ± 11.6 g), shoulder lateral forces (1.7 ± 0.7 kN vs 1.5 ± 0.2 kN), average rib deflection (29.8 ± 8.3 mm vs 28.4 ± 6.2 mm), spine accelerations at T4 (51.4 ± 23.4 g vs 39.6 ± 5.9 g) and T12 (56.3 ± 18.5 g vs 45.2 ± 9.6 g), iliac forces (1.9 ± 1.0 kN vs 1.2 ± 0.9 kN), and acetabular forces (1.9 ± 0.8 kN vs 1.3 ± 0.5 kN). The driver indicated statistically higher dynamic responses than the left rear passenger. Higher wheelbase vehicles generally showed lower occupant loading than the smaller vehicles. In conclusion, a reduction in occupant loading and risks for injury was observed in vehicle models over the past decade. This provides further insight into injury mechanisms, occupant dynamics simulations, and seat/restraint design.


2006 ◽  
Vol 11 (3) ◽  
pp. 273-280 ◽  
Author(s):  
B Fildes ◽  
O Bostrom ◽  
L Sparke ◽  
F Pintar ◽  
N Yoganandan

Author(s):  
Steven W. Kirkpatrick ◽  
Robert A. MacNeill ◽  
Francisco Gonzalez ◽  
Przemyslaw Rakoczy

There has been significant research in recent years to analyze and improve the impact behavior and puncture resistance of railroad tank cars. Ultimately, the results of this work will be used by the Government regulatory agencies in the United States and Canada to establish performance-based testing requirements and to develop methods to evaluate the crashworthiness and structural integrity of different tank car designs. This paper describes results of recent side impact testing and corresponding analyses using detailed finite element analyses (FEA). The test and analyses were performed to evaluate the side impact puncture performance of DOT-111 tank cars. The tank car was filled with water to approximately 97 percent of the volume. The tank was then sealed but not pressurized. The tank car was impacted at the Transportation Technology Center, Inc. by a 297,125-pound ram car with 12-by 12-inch ram head fitted to the ram car impacted the tank center. The analyses were on overall good agreement with the measured impact response. The lading was found to play a more significant role in the impact response than in previous testing and analyses of pressure tank cars. This is not surprising considering the reduced structural stiffness of the tanks compared to thicker pressure tank cars and the reduced effective stiffness from the initially unpressurized tank at impact. The smaller outage volume also contributes to a dramatic increase in the tank pressure as the dent formation reduces the tank volume and compresses the contents of the tank.


1979 ◽  
Author(s):  
R. W. Lowne ◽  
S. P. F. Petty ◽  
J. Harris ◽  
C. A. Hobbs
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document