Passenger Train Crashworthiness—Secondary Collisions

1996 ◽  
Vol 1531 (1) ◽  
pp. 13-19
Author(s):  
Subhasish Chatterjee ◽  
John F. Carney
Keyword(s):  
Companion Paper ◽  
Impact Response ◽  
Constitutive Relationship ◽  
Peak Acceleration ◽  
Passenger Train ◽  
Hybrid Iii ◽  
Occupant Injuries ◽  
The Impact

Secondary collisions in passenger train crashes are considered and a companion paper dealing with primary collisions is followed up. The effects of crash pulse magnitude and duration, occupant flail distance, and the nature of the impacted surface are considered. The constitutive relationship for a Hybrid III dummy head satisfying the peak acceleration requirements of FMVSS208 is developed and used with the crash victim simulator MADYMO to investigate the impact response of train passengers seated in a unidirectional layout. It is shown that the design of the coach shell and the interior have to be integrated to obtain train designs that will minimize occupant injuries in the event of train collisions.

scholarly journals Preliminary Reconstruction of the November 30, 2007, Chicago, IL Rail Collision

2011 ◽  
Author(s):  
Patricia Llana ◽  
David Tyrell
Keyword(s):  
Field Study ◽  
Preliminary Data ◽  
Structural Damage ◽  
Passenger Train ◽  
Occupant Protection ◽  
Causal Mechanisms ◽  
Occupant Injuries ◽  
The Impact

The Volpe Center is supporting the Federal Railroad Administration in performing rail passenger equipment crashworthiness research. The overall objective of this research is to develop strategies for improving structural crashworthiness and occupant protection. A field study of passenger train accidents is being conducted to investigate the causal mechanisms of the injuries incurred by train occupants. The investigation of the November 30, 2007 collision in Chicago, IL has provided preliminary data on the structural damage as well as occupant injuries resulting from the impact. This data will be used in simulations to guide the development of crashworthiness strategies.

A Comparison Between Head Impact Response of Hybrid III and THOR-NT Dummy Heads in FMVSS201 Tests

2006 ◽  
Author(s):  
Waseem Jaradat ◽  
Joseph Hassan ◽  
Guy Nusholtz ◽  
Khalil Taraman ◽  
Sanaa Taraman
Keyword(s):  
Block Design ◽  
Head Impact ◽  
Impact Response ◽  
Free Motion ◽  
Acceleration Response ◽  
Melt Temperature ◽  
Response Data ◽  
Operational Variables ◽  
Hybrid Iii ◽  
The Impact

The impact response of the forehead of both the Hybrid III dummy and THOR dummy was designed to the same human surrogate data. Therefore, when the forehead of either dummy is impacted with the same initial conditions, the acceleration response and consequently the head impact criterion HIC should be similar. If the THOR dummy is used in the FMVSS 201 free motion headform tests, then when it strikes the interior trim of the vehicle, as prescribed by the FMVSS 201 procedure, the acceleration response should be similar to that of the Hybrid III, as long as only the forehead engages the vehicle interior. To compare and contrast the response of the two dummy heads under FMVSS 201 testing, a design of experiments (DOE), that is a function of seven variables, is utilized to develop a mathematical model of the Head Impact Response. These independent parameters include five trim manufacturing process variables that relate to the interior that the dummy head hits in 201 testing: mold temperature, melt temperature, packing pressure, hold pressure, and injection speed. Two operational variables were also considered: free motion Headform approach angle and the dummy head drop calibration. An incomplete block design approach is utilized in order to significantly reduce the number of experiments. The DOE approach determines the response in the form of the Head Impact Criterion (HIC) with respect to the seven variables at 99% confidence level. The results describe the response data of both dummy heads. The response data of the dummy heads is described. Results indicate that the Hybrid III dummy head and the THOR dummy head have significantly different response characteristics in terms of magnitude of response, variation to different input conditions, repeatability, HIC values, and acceleration time history.

Comparative Evaluation of the THOR-NT and Hybrid-III in Sled and Vehicle Tests

2006 ◽  
Author(s):  
Ke Ding ◽  
Joseph Hassan ◽  
Guy Nusholtz
Keyword(s):  
Comparative Evaluation ◽  
Impact Response ◽  
Test Series ◽  
Limited Data ◽  
Hybrid Iii ◽  
The Impact

This paper compares the current THOR-NT and the Hybrid III in two different test series: The first series (series A) consisted of sled tests at 56 km per hour and a second series (series B) consisted of vehicle offset deformable barrier tests at 56 km per hour. Series A focused on comparing the repeatability of the impact response of the two dummies, in both full frontal and angled sled tests, for the head accelerations, thorax deflection and accelerations, pelvic accelerations, and neck loads. Series B focused on comparing the two dummies in a vehicle environment. The THOR dummy is considerably more complex than the Hybrid III and requires an increased workload in terms of handling and positioning, especially in a vehicle environment. With the limited data in this study, it was apparent that the THOR and Hybrid III have nominally the same level of repeatability. However, because of the increased instrumentation in the THOR, insights, in terms of impact response, can be obtained that cannot be obtained with the Hybrid III.

Identification of the Best Possible Configuration of the Shoulder Strap of a Three-Point Restraint for Motor Coach Occupant Rollover Protection

2011 ◽  
Author(s):  
Chandrashekhar K. Thorbole ◽  
David A. Renfroe ◽  
Hamid M. Lankarani
Keyword(s):  
Seat Belt ◽  
Essential Element ◽  
The United States ◽  
Computational Technique ◽  
Hybrid Iii ◽  
Roll Rate ◽  
Occupant Injury ◽  
Occupant Injuries ◽  
Serious Injuries ◽  
The Impact

The motor coach is an essential element of the mass transportation system in the United States and all around the globe. Rollover accidents associated with any motor coach without an adequate occupant protection system may result in serious or fatal occupant injuries. The seat belt is an essential safety device in protecting an occupant in a rollover accident. It has been observed that just a quarter roll of a bus results in fatal injuries to an unbelted occupant. This severe nature of occupant injury in a less severe bus roll is attributable to the large flying distance within the unpadded interior and the impact with other fellow occupants. In this situation the presence of a seat belt is mandatory to protect the occupants from serious injuries by preventing their ejection from their seats. The three-point restraint is the best possible solution for the motor coach seat belt requirement. The understanding of shoulder strap placement with respect to the occupant is important information. This information facilitates the best possible seat belt configuration for all occupants which will minimize the slippage of the shoulder strap during a rollover accident. The slipping of the shoulder strap is a function of rollover type, rollover direction, roll rate and the occupant location in a vehicle with respect to roll direction. A Finite Element bus model is used to conduct a trip rollover simulation at two different trip velocities. The motion file, as obtained from this simulation, is used to prescribe motion to a MADYMO facet bus model. The standard Hybrid III 50th percentile ATD (Anthropomorphic Test Device) is used to model all the belted occupants. The FE belt model is used to facilitate the simulation of slippage on the shoulder. This study demonstrates the best possible configuration of the three-point restraints for motor coach occupants in a rollover accident using the computational technique. Knowledge of this kind will help the industry to identify and implement seat belts with the best configuration for occupant rollover protection.

Influence of Ply Stacking Sequences on the Impact Response of Carbon Fibre Reinforced Polymer Composite Laminates

2019 ◽  
Author(s):  
Kristian Gjerrestad Andersen ◽  
Gbanaibolou Jombo ◽  
Sikiru Oluwarotimi Ismail ◽  
Segun Adeyemi ◽  
Rajini N ◽  
...  
Keyword(s):  
Carbon Fibre ◽  
Polymer Composite ◽  
Composite Laminates ◽  
Impact Response ◽  
Reinforced Polymer ◽  
Carbon Fibre Reinforced Polymer ◽  
Fibre Reinforced Polymer ◽  
The Impact

scholarly journals Viscous-like forces control the impact response of shear-thickening dense suspensions

2021 ◽  
Vol 923 ◽  
Author(s):  
Marc-Andre Brassard ◽  
Neil Causley ◽  
Nasser Krizou ◽  
Joshua A. Dijksman ◽  
Abram. H. Clark
Keyword(s):  
Shear Thickening ◽  
Impact Response ◽  
Dense Suspensions ◽  
The Impact

Abstract

Effect of long-term moisture exposure on impact response of glass-reinforced vinylester

2021 ◽  
pp. 147509022199616
Author(s):  
Fatemeh Alizadeh ◽  
Navid Kharghani ◽  
Carlos Guedes Soares
Keyword(s):  
Water Uptake ◽  
Failure Modes ◽  
Sea Water ◽  
Composite Plates ◽  
Impact Response ◽  
Low Velocity Impact ◽  
Water Type ◽  
Interfacial Damage ◽  
Impact Properties ◽  
The Impact

Glass/Vinylester composite laminates are comprehensively characterised to assess its impact response behaviour under moisture exposure in marine structures. An instrumented drop weight impact machine is utilised to determine the impact responses of dry and immersed specimens in normal, salted and sea water. The specimens, which had three different thicknesses, were subjected to water exposure for a very long period of over 20 months before tested in a low-velocity impact experiment. Water uptake was measured primarily to study the degradation profiles of GRP laminates after being permeated by water. Matrix dissolution and interfacial damage observed on the laminates after prolonged moisture exposure while the absorption behaviour was found typically non-Fickian. The weight of the composite plates firstly increased because of water diffusion up to month 15 and then decreased due to matrix degradation. The specimens with 3, 6 and 9 mm thickness exhibited maximum water absorption corresponding to 2.6%, 0.7% and 0.5% weight gain, respectively. In general, the results indicated that water uptake and impact properties were affected by thickness and less by water type. Impact properties of prolonged immersed specimens reduced remarkably, and intense failure modes detected almost in all cases. The least sensitive to impact damage were wet specimens with 9 mm thickness as they indicated similar maximum load and absorbed energy for different impact energies.

Response and failure modes of biaxial warp-knitted flexible composite subject to low-velocity impact

2021 ◽  
pp. 152808372110154
Author(s):  
Ziyu Zhao ◽  
Tianming Liu ◽  
Pibo Ma
Keyword(s):  
Impact Energy ◽  
Linear Density ◽  
Failure Modes ◽  
Impact Response ◽  
Low Velocity Impact ◽  
Minor Effect ◽  
Low Velocity ◽  
Velocity Impact ◽  
Flexible Composites ◽  
The Impact

In this paper, biaxial warp-knitted fabrics were produced with different high tenacity polyester linear density and inserted yarns density. The low-velocity impact property of flexible composites made of polyurethane as matrix and biaxial warp-knitted fabric as reinforcement has been investigated. The effect of impactor shape and initial impact energy on the impact response of flexible composite is tested. The results show that the initial impact energy have minor effect on the impact response of the biaxial warp-knitted flexible composites. The impact resistance of flexible composite specimen increases with the increase of high tenacity polyester linear density and inserted yarns density. The damage morphology of flexible composite materials is completely different under different impactor shapes. The findings have theoretical and practical significance for the applications of biaxial warp-knitted flexible composite.

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