Development and Fabrication of State-of-the-Art End Structures for Budd M1 Cars

2009 Joint Rail Conference

Tyrell

2009

To support the development of a proposed rule [1], a fullscale dynamic test and two full-scale quasi-static tests have been performed on the posts of a state-of-the-art (SOA) end frame. These tests were designed to evaluate the dynamic and quasi-static methods for demonstrating energy absorption of the collision and corner posts. The tests focused on the collision and corner posts individually because of their critical positions in protecting the operator and passengers in a collision where only the superstructure, not the underframe, is loaded. There are many examples of collisions where only the superstructure is loaded.For the dynamic test, a 14,000-lb cart impacted a standing cab car at a speed of 18.7 mph. The cart had a rigid striking surface in the shape of a coil mounted on the leading end that concentrated the impact load on the collision post. During the dynamic test the collision post deformed approximately 7.5 inches, and absorbed approximately 137,000 ft-lbs of energy. The SOA collision post was successful in preserving space for the operators and the passengers.For the quasi-static test of the collision post, the collision post was loaded in the same location and with the same fixture as the dynamic test. The post absorbed approximately 110,000 ft-lb of energy in 10 inches of permanent, longitudinal deformation. For the quasi-static test of the corner post, the post was loaded at the same height as the collision post, with the same fixture. The corner post absorbed 136,000 ft-lb of energy in 10 inches of permanent, longitudinal deformation.The series of tests was designed to compare the dynamic and quasi-static methods for measuring collision energy absorption during structural deformation as a measure of crashworthiness. When properly implemented, either a dynamic or quasi-static test can demonstrate the crashworthiness of an end frame. INTRODUCTIONThree tests were designed to demonstrate test methods and to measure the crashworthiness of the Federal Railroad Administration (FRA) prototype end frame design. The prototype design, referred to as the state-of-the-art (SOA) design, has enhanced loading capabilities. A proposed rule allows for either quasi-static or dynamic evaluation scenarios for the two major end frame components: the collision and corner posts. By requiring energy absorption capabilities for new end frames, the rule aims to improve survivability for operators and passengers at higher collision speeds. This paper covers work done to support a proposed rule: a dynamic test of a collision post, a quasi-static test of a collision post, and a quasi-static test of a corner post. The work is used both to support the development of the rule and to assist the government and industry in building and evaluating structures built to the standards of the proposed rule.

Section: Previous Testsmentioning

confidence: 99%

Dynamic and Quasi-Static Grade Crossing Collision Tests

̈hlanger

2009 Joint Rail Conference

Tyrell

2009

“…Shelves and bulkhead sheets connect the collision and corner posts, allowing some load to be shared between the two posts. The end frame is better supported by a continuous side sill and robust roof rails [4,5]. Table 1 shows the full-scale tests that have been performed as part of the grade-crossing scenario research.…”

Section: Passenger Crashworthiness Programmentioning

confidence: 99%

“…The stresses in the rest of the cart are well below their 39-ksi yield strength. A final FEA was conducted with the cab car and the cart [5]. In this analysis, the cart was modeled as rigid and impacted the collision post of the cab car at 21 mph.…”

Section: Figure 5: Finished Proxy Object Cartmentioning

confidence: 99%

“…Finite element analyses (FEA) were conducted in ABAQUS 6.7-1 to determine the mode of deformation of the cart, to confirm that the cart could withstand an impact with the cab car, without permanent deformation [5]. Analyses were also conducted to determine the gross motions of the cart and the cab car as a result of the impact, and particularly to ensure that the impact with the cart would not cause the cab car to derail.…”

Section: Figure 5: Finished Proxy Object Cartmentioning

confidence: 99%

See 1 more Smart Citation

A Dynamic Test of a Collision Post of a State-of-the-Art End Frame Design

Priante

ASME 2008 Rail Transportation Division Fall Technical Conference

Jacobsen

et al. 2008

In support of the Federal Railroad Administration's (FRA) Railroad Equipment Safety Program, a full-scale dynamic test of a collision post of a state-of-the-art (SOA) end frame was conducted on April 16, 2008. The purpose of the test was to evaluate the dynamic method for demonstrating energy absorption and graceful deformation of a collision post.The post aims to protect the operators and passengers in the event of a collision where only the superstructure, not the underframe, is loaded. Methods for improving the performance of collision and corner posts were prompted by accidents such as the fatal collision in Portage, Indiana in 1998, where a coil of steel sheet metal penetrated the cab car through the collision post.The improvements made for the SOA end frame structure include more substantial corner and collision posts, robust post connections to the buffer beam and anti-telescoping (AT) beam, and corner and collision posts integrated with a shelf and bulkhead sheet. Full length side sills improved support for the end frame. This test focused on one collision post because of its critical position in protecting the operator and passengers in an impact with an object at a grade-crossing.For the test, a 14,000-lb cart impacted a standing cab car at a speed of 18.7 mph. The cart had a rigid coil shape mounted on the leading end that concentrated the impact load on the collision post. The requirements for protecting the operator's space state that there will be no more than 10 inches of longitudinal crush and none of the attachments of any of the structural members separate.During the test, the collision post deformed approximately 7.4 inches and absorbed approximately 138,000 ft-lb of energy. The attachment between the post and the AT beam remained intact. The connection between the post and the buffer beam did not completely separate, however the forward flange and both side webs fractured. The post itself did not completely fail. There was material failure in the back and the sides of the post at the impact location. Overall, the end frame was successful in absorbing energy and preserving space for the operators and the passengers. INTRODUCTIONAs a result of consideration of both a notice of proposed rulemaking (NPRM) for improved cab car multiple unit (MU) locomotive equipment and the accepted industry standard, a series of tests were planned to demonstrate examples of conducting such tests to shows equivalence between testing protocols. Three test scenarios are taken from the FRA's proposed rule [1]. This paper covers the dynamic test of a collision post. There are two quasi-static tests also being planned. The quasi-statics tests are on the collision post and the corner post.Both the proposed rule and the industry standard improve crashworthiness performance due to increased static load requirements, as well as minimum energy absorption and maximum allowable intrusion into the cab. By encouraging improved energy absorption capabilities for the end frames, the rule aims to improve survivability for ...

“…The passenger car used in the tests conducted in support of the new FRA standard was a Budd M1 passenger car retrofitted with an SOA end frame structure. The SOA end frame, shown in Figure 2 retrofitted to a Budd M1 car, includes more substantial collision and corner posts, more robust post connections to the buffer beam and anti-telescoping (AT) beam, shelves and bulkhead sheets that are integrated with the collision and corner posts, and stronger end frame support with full-length side sills [5] [6]. …”

Section: Fra-compliant End Frame Designmentioning

confidence: 99%

Structural Crashworthiness Standards Comparison: Grade-Crossing Collision Scenarios

ASME 2009 Rail Transportation Division Fall Technical Conference

2009

In support of the Federal Railroad Administration's (FRA) Railroad Equipment Safety Program, American and European grade-crossing collision scenarios were evaluated and compared. Finite element analyses (FEA) were employed to subject an FRA-compliant passenger car to grade-crossing collision scenarios defined in both the proposed FRA Code of Federal Regulations (CFR) and European Standard (EN) 15227. The proposed FRA collision scenario involved a single car impacted by a cart. The cart had a punch mounted to it to hit a specific post of the end frame of the car. The EN 15227 collision scenario involved a complete train consist impacting a large deformable obstacle that approximates a lorry. The analyses show that these collision scenarios, while both gradecrossing scenarios, are very different not only in terms of the impact object and the amount of initial kinetic energy involved, but also in terms of how the car is loaded and deformed during impact. The FRA scenario is shown to be easier to analyze as well as easier to test than the EN 15227 scenario. Additionally, the FRA scenario is safer to test because of the levels of initial energy involved. The FRA scenario also provides clearer metrics of success. The FRA-compliant car utilized in the analyses and test conducted for this paper passed both FRA and EN 15227 grade-crossing collision scenarios according to the requirements for each respective standard. However, the analyses show that despite both scenarios providing for energy absorption in a grade-crossing collision, because the manner in which the car is loaded and deformed (concentrated vs. distributed) is different, the FRA performance standard and EN 15227 grade-crossing collision scenarios are not equivalent and mutual compliance is not guaranteed.