Development and Testing of Structurally Independent Foundations for High-Speed Containment Concrete Barrier

2021 ◽  
pp. 036119812098032
Author(s):  
James Kovar ◽  
Nauman Sheikh ◽  
Roger Bligh ◽  
Sofokli Cakalli ◽  
Taya Retterer ◽  
...  
Keyword(s):  
Finite Element ◽  
High Speed ◽  
Full Scale ◽  
Drilled Shaft ◽  
Site Conditions ◽  
Critical Systems ◽  
Crash Testing ◽  
Wide Range ◽  
Slab Foundation ◽  
Test Level

This paper presents the development and testing of single slope barriers with independent foundations that can be installed at a wide range of site conditions. The researchers developed designs of barriers with foundation systems by conducting a series of finite element simulations and performing full-scale vehicle impact tests under the American Association of State Highway and Transportation Officials’ (AASHTO) Manual for Assessing Safety Hardware ( MASH) Test Level 5 (TL-5) and Test Level 4 (TL-4) conditions. In this process, foundation designs were developed for site conditions that may require shallow foundations, or foundations that have a smaller footprint. Depending on the site conditions and the presence of underground structures, designers could select the most fitting option from these designs. Impact performance of the developed barrier and foundation systems was evaluated using full-scale finite element impact simulations under MASH TL-5 and TL-4 impact conditions. Two critical systems were selected for full-scale crash testing: a 54 in. tall single slope barrier with drilled shaft foundations, and a 36 in. tall single slope barrier with moment slab foundation. The barrier with the drilled shaft foundation system was tested to MASH Test 5-12 conditions, and the barrier with the moment slab foundation system was tested to MASH Test 4-12 conditions. Both systems performed acceptably with respect to the MASH criteria. This paper presents the various barrier and foundation designs that were developed, key results from the simulation analyses, and details of the crash testing performed on the two selected systems.

Finite Element Simulation of a Strong-Post W-Beam Guardrail System

SIMULATION ◽  
2002 ◽  
Vol 78 (10) ◽  
pp. 587-599 ◽  
Author(s):  
Ali O. Atahan
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Full Scale ◽  
Nonlinear Finite Element ◽  
Crash Test ◽  
Original Design ◽  
Dynamic Interactions ◽  
Crash Testing ◽  
Element Simulation ◽  
Test Requirements

Computer simulation of vehicle collisions has improved significantly over the past decade. With advances in computer technology, nonlinear finite element codes, and material models, full-scale simulation of such complex dynamic interactions is becoming ever more possible. In this study, an explicit three-dimensional nonlinear finite element code, LS-DYNA, is used to demonstrate the capabilities of computer simulations to supplement full-scale crash testing. After a failed crash test on a strong-post guardrail system, LS-DYNA is used to simulate the system, determine the potential problems with the design, and develop an improved system that has the potential to satisfy current crash test requirements. After accurately simulating the response behavior of the full-scale crash test, a second simulation study is performed on the system with improved details. Simulation results indicate that the system performs much better compared to the original design.

scholarly journals Running Performance and Hormonal, Maturity and Physical Variables in Starting and Non-Starting Elite U14 Soccer Players During a Congested Match Schedule

2021 ◽  
Vol 80 (1) ◽  
pp. 287-295
Author(s):  
Vinicius Zanetti ◽  
Marcelo Saldanha Aoki ◽  
Paul Bradley ◽  
Christopher Carling ◽  
Thomas Kisil Marino ◽  
...  
Keyword(s):  
High Speed ◽  
Soccer Players ◽  
Running Performance ◽  
Salivary Testosterone ◽  
Youth Soccer ◽  
Wide Range ◽  
Significant Difference ◽  
The Difference ◽  
Biological Maturity ◽  
Test Level

Abstract This study examined changes in match running performance (MRP) in Under-14 soccer players (13.5 ± 0.7 yrs) during a congested match schedule (CMS) (4 matches played within a 5-day period). It also examined the difference in salivary testosterone (sT) concentration, somatic maturation, jumping tests, and Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1) between the players selected to play (SLG; group who participated in all matches) and players non-selected to play (NSG). A significant difference was observed for the frequency of decelerations (DEC) across matches (match 4 vs. matches 1, 2 and 3; p = 0.05; partial ƞ2 = 0.20). No difference between matches was observed for total running distance (TRD), high-speed running distance (HSRD), and frequency of accelerations (ACC) (p > 0.05). A wide range for within-player coefficient of variation (CV) values was observed for all MRP variables (range: 10.5 = TRD to 30.6 = HSRD). No difference between SLG and NSG for any of the assessed variables was observed (p > 0.05). The findings suggest that DEC was the most pertinent variable for monitoring changes in MRP during the CMS. In addition, at an elite youth soccer level, the biological maturity and fitness might not influence selection to play.

Interaction Between Single Unit Trucks and Concrete Barriers in High Speed Impacts

2007 ◽  
Author(s):  
John D. Reid ◽  
Ronald K. Faller
Keyword(s):  
Single Unit ◽  
High Speed ◽  
High Volume ◽  
Full Scale ◽  
Single Units ◽  
Next Generation ◽  
Crash Testing ◽  
Concrete Barriers ◽  
Recommended Practices

Single Units Trucks (SUT’s) are commonly used for hauling many things and typically have a loaded mass between 8,000 to 10,000 kg (18,000 and 23,000 lbs). Concrete barriers are commonly used on high volume traffic highways that have very little median space between opposing traffic lanes. The interaction between SUT’s and concrete barriers during impacts at speeds between 80–90 km/h (50–56 mph) at angles up to 15 degrees is of importance not only to the driver, but also to the surrounding traffic. Of particular concern is the vehicle rolling-over the barrier. This study investigates some recent full-scale crash testing and simulation of SUT’s into concrete barriers. Information gained from this study is being used to help determine the next generation of recommended practices and procedures for designing and testing concrete barriers, as well as other types of barriers, like bridge-rails.

NCHRP Report 350 Testing of W-Beam Slotted-Rail Terminal

1997 ◽  
Vol 1599 (1) ◽  
pp. 22-31 ◽  
Author(s):  
King K. Mak ◽  
Hayes E. Ross ◽  
Roger P. Bligh ◽  
Wanda L. Menges
Keyword(s):  
High Speed ◽  
Safety Performance ◽  
The Other ◽  
Federal Aid ◽  
Speed Limits ◽  
Crash Testing ◽  
National Highway ◽  
Level 3 ◽  
Test Level ◽  
Highway System

Two slotted-rail terminal (SRT) designs, one for use on roadways with speed limits of 72.4 km/hr (45 mi/hr) or less and the other for high-speed facilities, were previously developed and successfully crash-tested in accordance with guidelines set forth in NCHRP Report 230. Those SRT designs have been approved by FHWA for use on federal-aid projects. However, FHWA has since adopted NCHRP Report 350 as the official guidelines for safety performance evaluation of roadside features and required that all roadside features to be used on the National Highway System be crash-tested in accordance with the NCHRP Report 350 guidelines by 1998. It is therefore necessary to modify and retest the SRT designs in accordance with NCHRP Report 350 guidelines. The modified SRT design has successfully met the guidelines set forth in NCHRP Report 350 for Test Level 3 conditions, that is, 100-km/hr (62.2 mi/hr) and the results of the crash testing. The modified SRT design has been approved by FHWA for use on the national highway system.

Development of a New Manual for Assessing Safety Hardware TL-3 Low-Profile Portable Concrete Barrier for High-Speed Applications

2019 ◽  
Vol 2673 (7) ◽  
pp. 630-640
Author(s):  
Chiara Silvestri Dobrovolny ◽  
Shengyi Shi ◽  
James Kovar ◽  
Roger P. Bligh ◽  
Stefan Hurlebaus
Keyword(s):  
High Speed ◽  
Evaluation Criteria ◽  
Full Scale ◽  
Crash Testing ◽  
Sight Distance ◽  
Low Profile ◽  
Rail Systems ◽  
Distance Problem ◽  
Crash Tests ◽  
Concrete Barrier

A sight-distance problem is associated with use of 32-in. tall concrete longitudinal barriers, specifically in certain work zone locations and at nighttime. These 32-in. tall barriers can obstruct drivers’ eyesight, making it difficult for drivers to detect oncoming vehicles on the other side of these barriers. To address this sight-distance problem while protecting the errant vehicles, researchers at the Texas Transportation Institute (TTI) developed a 20-in. tall low-profile portable concrete barrier (PCB) for use in low-speed work zones in the early 1990s. To address the problem for high-speed application, TTI researchers applied modifications to the 20-in. tall low-profile PCB. Researchers designed two retrofit metal rail systems to be added on top of the existing 20-in. tall low-profile PCB to address roadside and median applications. The systems successfully performed in full-scale crash testing according to NCHRP Report 350 Test Level (TL) 3 evaluation criteria. This paper describes the efforts to develop and evaluate the crashworthiness of a new low-profile PCB design for high-speed applications. The crash tests were performed following Manual for Assessing Safety Hardware (MASH) guidelines and evaluation criteria. Based on results from finite element computer simulations performed to aid design, MASH full-scale crash tests were conducted on a low-profile PCB system comprised of 26-in. tall, 30-ft long barrier segments, with a T-shaped profile. Based on constructability feedback, the sides of the barrier were formed with a negative 1:18 slope, which allows for ease of construction forming. The new low-profile PCB performed acceptably as a MASH TL-3 longitudinal barrier.

scholarly journals Development of a Test Level 3 Transition Between Guardrail and Portable Concrete Barriers

2017 ◽  
Vol 2638 (1) ◽  
pp. 77-87 ◽  
Author(s):  
Robert W. Bielenberg ◽  
David Gutierrez ◽  
Ronald K. Faller ◽  
John D. Reid ◽  
Phil Tenhulzen
Keyword(s):  
Systems Design ◽  
Road Construction ◽  
Full Scale ◽  
Performance Criteria ◽  
Work Zones ◽  
Design Concepts ◽  
Crash Testing ◽  
Concrete Barriers ◽  
Level 3 ◽  
Test Level

Road construction often requires that work zones be created and shielded by portable concrete barriers (PCBs) to protect workers and equipment from errant vehicles as well as to prevent motorists from striking other roadside hazards. For an existing W-beam guardrail system installed adjacent to the roadway and near the work zone, guardrail sections are removed so a PCB system can be placed. A study was done to develop a crashworthy transition between W-beam guardrail and PCB systems. Design concepts were developed and refined through computer simulation with LS-DYNA. Additionally, a study of critical impact points was conducted to determine impact locations for full-scale crash testing. The design effort resulted in a new system consisting of a Midwest Guardrail System that overlapped a series of F-shape PCB segments placed at a 15:1 flare. In the overlapped region of the barrier systems, uniquely designed blockout supports and a specialized W-beam end shoe mounting bracket were used to connect the systems. Three full-scale vehicle crash tests were successfully conducted according to the Manual for Assessing Safety Hardware Test Level 3 safety performance criteria. Because of the successful test results, a Test Level 3 crashworthy guardrail-to-PCB transition system is now available for protecting motorists, workers, and equipment in work zones.

scholarly journals Analysis methods of the dynamic structural stress in a full-scale welded carbody for high-speed trains

2018 ◽  
Vol 10 (10) ◽  
pp. 168781401880591 ◽  
Author(s):  
Yaohui Lu ◽  
Heyan Zheng ◽  
Chuan Lu ◽  
Tianli Chen ◽  
Jing Zeng ◽  
...  
Keyword(s):  
Finite Element ◽  
High Speed ◽  
Large Scale ◽  
Dynamic Stress ◽  
Full Scale ◽  
Structural Stress ◽  
Random Load ◽  
Analysis Methods ◽  
Welded Structure ◽  
High Speed Trains

The calculation of the dynamic stress of a large and complex welded carbody is the key to the fatigue design and the durability evaluation of the carbody. Adopting the advanced structural stress based on the finite element method, a new finite element transformation method between random loads and dynamic stresses is proposed to be applied in carbody for high-speed trains. The multi-axial random dynamic load spectrums of full-scale carbody are obtained by the vehicle system dynamics method, and the shell finite element model of a full-scale carbody is established. Adopting the concept of a surrogate model, the finite element transformation relationship between the random load and the dynamic structural stress at concerned points is constructed by using multidisciplinary methods to compute the dynamic stress spectrums of concerned points at the welding seam, and dynamic structural stresses are compared and validated through carbody rig-test. The analysis methods of dynamic structural stress are performed systematically for a full-scale welded structure, which provides reference methods for the fatigue durability evaluation of large-scale welded structures.

Long-Span Guardrail System for Culvert Applications

2000 ◽  
Vol 1720 (1) ◽  
pp. 19-29 ◽  
Author(s):  
Ronald K. Faller ◽  
Dean L. Sicking ◽  
Karla A. Polivka ◽  
John R. Rohde ◽  
Bob W. Bielenberg
Keyword(s):  
Simulation Modeling ◽  
Research Study ◽  
Full Scale ◽  
Wood Block ◽  
Long Span ◽  
Crash Testing ◽  
Vehicle Crash ◽  
Level 3 ◽  
Crash Tests ◽  
Test Level

A long-span guardrail for use over low-fill culverts was developed and successfully crash tested. The guardrail system was configured with 30.48 m of nested, 12-gauge W-beam rail and centered around a 7.62-m-long unsupported span. The nested W-beam rail was supported by 16 W152×13.4 steel posts and 6 standard CRT posts, each with two 150-mm×200×360 mm wood block-outs. Each post was 1830 mm long. Post spacings were 1905 mm on center, except for the 7.62-m spacing between the two CRT posts surrounding the long span. The research study included computer simulation modeling with Barrier VII and full-scale vehicle crash testing, using 3/4-ton (680-kg) pickup trucks in accordance with the Test Level 3 (TL-3) requirements specified in NCHRP Report 350. Three full-scale vehicle crash tests were performed. The first test was unsuccessful because of severe vehicle penetration into the guardrail system. This penetration resulted from a loss of rail tensile capacity during vehicle redirection when the swagged fitting on the cable anchor assembly failed. A second test was performed on the same design, which contained a new cable anchor assembly. During vehicle redirection, the pickup truck rolled over and the test was considered a failure. The long-span system was subsequently redesigned to incorporate double block-outs on the CRT posts and crash tested again. Following the successful third test, the long-span guardrail system was determined to meet TL-3 criteria.

Full-Scale Crash Testing Facilities for a Railway Vehicle

2012 ◽  
Author(s):  
Jin Sung Kim ◽  
Hyun Seung Jung ◽  
Tae Soo Kwon ◽  
Won Mok Choi ◽  
Seung Wan Son
Keyword(s):  
High Speed ◽  
Impact Test ◽  
Full Scale ◽  
Displacement Sensor ◽  
Crash Test ◽  
Railway Vehicle ◽  
Single Item ◽  
Railway Vehicles ◽  
Crash Testing ◽  
The Impact

KRRI (Korea Railroad Research Institute) has successfully performed several tens of impact tests of crash parts for a railway vehicles. Full-scale crash testing facilities were newly established including a crash barrier, dynamic load cell, high speed DAS (Data Acquisition System), a laser displacement sensor, dummies, a motor car and etc. This paper introduces series of impact test results using full-scale crash testing facilities. The impact test for railway vehicles consists of three categories, i.e. single item tests, module tests and crash structure tests. For single item tests, expansion tubes, composite tubes, collapsible tubes and etc. were tested. For module tests, a crash test of a light collision safety device with an expansion tube and triggering mechanism was performed. For crash structure tests, several full-scale crash tests were performed including front-end and cab structures with or without dummies. The crash testing equipment developed will be able to evaluate the occupant safety as well as the structural crashworthiness of a train.

An Extrema Approach to Probabilistic Creep Modeling in Finite Element Analysis

2021 ◽  
Author(s):  
Md Abir Hossain ◽  
Jacqueline R Cottingham ◽  
Calvin M. Stewart
Keyword(s):  
Finite Element ◽  
Goodness Of Fit ◽  
Full Scale ◽  
Spatial Uncertainty ◽  
304 Stainless Steel ◽  
Computational Time ◽  
Extremum Condition ◽  
Wide Range ◽  
Extremum Conditions ◽  
2D Model

Abstract This paper introduces a computationally efficient extremum condition-based Reduced Order Modeling (ROM) approach for the probabilistic predictions of creep in finite element (FE). Component-level probabilistic simulations are needed to assess the reliability and safety of high-temperature components. Full-scale probabilistic creep models in FE are computationally expensive, requiring many hundreds of simulations to replicate the uncertainty of component failure. In this study, an extremum condition-based ROM approach is proposed. In the extremum approach, full-scale probabilistic simulations are completed in 1D across a wide range of stresses, the data is processed and extremum conditions extracted, and those conditions alone are applied in 2D/3D FE to predict the mean and range of creep-failure. The probabilistic Sinh model, calibrated for alloy 304 stainless steel, is selected . The uncertainty sources (i.e. test condition, pre-existing damage, and model constants) are evaluated and pdfs sampling are performed via Monte carlo method. The extremum conditions are chosen from numerous 1D model simulations. These conditions include extremum cases of creep ductility, rupture, and area under creep curves. Only the extremum cases are simulated for 2D model saving significant computational time and memory. The goodness-of-fit of the predicted creep response for 1D and 2D model shows satisfactory agreement with the experimental data. The accuracy of the extremum condition-based ROM will reduce significant computational burden of simulating complex engineering systems. Introduction of multi-stage Sinh, stochasticity, and spatial uncertainty will further improve the prediction.

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