Development of an Approach Guardrail Transition Attached to a Thrie Beam and Channel Bridge Railing
Author :
Publisher :
Page : 168 pages
File Size : 42,94 MB
Release : 2000
Category : Bridge railings
ISBN :
Crash Testing and Evaluation of the HDOT's Thrie-beam Approach Guardrail Transition Attached to 42-in. Tall, Solid Concrete Bridge Rail with Aesthetic Recessed, Rounded Panels and 6-ft. Wide Sidewalk
Author : Tewodros Y. Yosef
Publisher :
Page : 0 pages
File Size : 33,66 MB
Release : 2022
Category : Bridge railings
ISBN :
Book Description
Two Approach Guardrail Transitions for Concrete Safety Shape Barriers
Author :
Publisher :
Page : 172 pages
File Size : 15,87 MB
Release : 1998
Category : Impact
ISBN :
Book Description
Two approach guardrail transitions for use with concrete safety shape barriers were developed and crash tested. For this study, the transition systems were attached to the New Jersey safety shape concrete barrier; however, it is believed that these transition systems could be easily adapted to the F-shape barrier with no need for further crash testing. Both transition designs were constructed with two nested thrie beam rails measuring 2.66-mm thick. The first transition design was supported by nine W150x13.5 steel posts measuring, 1,981-mm long, while the second transition design was supported by nine 152-mm x 203-mm wood posts measuring 2,134-mm long. For both systems, post spacings consisted on one at 292 mm, five at 476 mm, and three at 952 mm. A triangular-shape concrete curb was constructed below the thrie beam rail on each approach guardrail transition system. The two transition systems successfully met the Test Level 3 requirements specified in NCHRP Report 350, "Recommended Procedures for the Safety Performance Evaluation of Highway Features."
Development of a MASH TL-3 Approach Guardrail Transition to a MASH TL-4 Steel Bridge Rail
Author : Jennifer D. Rasmussen
Publisher :
Page : 321 pages
File Size : 34,92 MB
Release : 2020
Category : Bridges
ISBN :
Book Description
A Manual for Assessing Safety Hardware (MASH) Test Level 3 (TL-3) approach guardrail transition (AGT) was designed to connect the Midwest Guardrail System (MGS) to a MASH TL-4 steel-post, steel-tube, bridge rail, Type IL-OH. Two connection concepts were evaluated using the LS-DYNA finite element analysis computer software. The second concept was selected for further evaluation with full-scale crash testing, which included a previously-developed, thrie-beam, approach guardrail transition, modified HSS8x6x1/4 transition tube rails that aligned with the lower and middle bridge rail tubes, and new connection hardware designed to prevent vehicle snag during reverse-direction impacts. The critical impact points were selected using LS-DYNA for MASH test designation nos. 3-20 and 3-21 in the impact direction from the thrie-beam to the bridge rail. MASH test designation nos. 3-20 and 3-21 in the impact direction from the bridge rail to the thrie-beam AGT were determined to be non-critical. In test no. STBRT-1, the 2,404-lb small car impacted the AGT at a speed of 64.6 mph, an angle of 25.2 degrees, and at a location 21.3 in. upstream from post no. 19, thus resulting in an impact severity of 60.9 kip-ft. The small car was contained and redirected and resulted in a successful test according to MASH test designation no. 3-20 safety performance criteria. In test no. STBRT-2, the 5,007-lb quad cab pickup truck impacted the AGT at a speed of 62.7 mph, an angle of 24.9 degrees, and at a location 15.9 in. upstream from post no. 19, thus resulting in an impact severity of 116 kip-ft. The pickup truck was contained and redirected and resulted in a successful test according to MASH test designation no. 3-21 safety performance criteria.
Development of Guardrail to Bridge Rail Transition
Author : Roger P. Bligh
Publisher :
Page : 152 pages
File Size : 40,46 MB
Release : 1988
Category : Bridge railings
ISBN :
Book Description
This report describes the development and testing of a guardfence-to-rigid bridge rail transition. The transition consists of a tubular W-beam supported on 7 inch diameter round wood posts. It is designed to transition to a vertical wall or to the concrete safety shaped barrier. It can be used on new construction or as a retrofit for existing installations. Based on a full-scale vehicular crash test program, the design was judged to be in compliance with recommended impact performance criteria as presented in NCHRP Report 230. Also described is a tentative design for approach guardfence at bridge ends near an abutting roadway. The design consists of short radius, curved guardrail supported on weakened round wood posts.
Evaluation of Roadside Features to Accommodate Vans, Minivans, Pickup Trucks, and 4-wheel Drive Vehicles
Author : Hayes E. Ross
Publisher : Transportation Research Board
Page : 103 pages
File Size : 26,20 MB
Release : 2002
Category : Four-wheel drive vehicles
ISBN : 0309067502
Book Description
Guardrail-bridge Rail Transition Designs
Author :
Publisher :
Page : 192 pages
File Size : 29,80 MB
Release : 1988
Category : Bridge railings
ISBN :
Book Description
MASH TL-3 Evaluation of Guardrail to Rigid Barrier Transition Attached to Bridge Or Culvert Structure
Author : William F. Williams (Transportation engineer)
Publisher :
Page : 0 pages
File Size : 33,67 MB
Release : 2020
Category : Automobiles
ISBN :
Book Description
Texas Transportation Institute (TTI) researchers performed an extensive literature review of bridge railing transitions crash tested to Manual for Assessing Safety Hardware (MASH) TL-3, and incorporated the information obtained from this review into the design and details for the new transition testing developed for this project. TTI researchers developed concepts for the new transition anchored to a concrete wing wall. TTI researchers developed a full-scale, three-dimensional finite element model of the guardrail transition. The modeling effort included developing and validating a subcomponent level model of the post installed on concrete. Upon completion of the simulations, TTI researchers processed the results and assessed the likelihood of the transition system passing the required MASH crash tests. TTI researchers noted the design deficiencies and recommended design modifications to the system to mitigate those deficiencies. TTI researchers developed full-scale test installation drawings of the design after the finite element model simulations were completed and all the results were reviewed with favorable results. After approval of the test installation drawings by Texas Department of Transportation (TxDOT), construction of a full-scale test installation for crash testing commenced, and crash tests were performed on the full-scale test installation. The Guardrail to Rigid Barrier Transition Attached to Bridge or Culvert Structure, used on the upstream and downstream ends, performed acceptably for MASH TL-3 transitions.
Thrie Beam Retrofit Bridge Rail and Transition
Author : Joseph B. Mayer
Publisher :
Page : 117 pages
File Size : 40,45 MB
Release : 1990
Category : Bridge railings
ISBN :
Book Description
This report presents the results of four vehicle crash tests on guardrail systems.
Evaluation of Bridge Approach Rails
Author : Roger P. Bligh
Publisher :
Page : 200 pages
File Size : 39,67 MB
Release : 1992
Category : Bridge railings
ISBN :
Book Description
A recent study on the performance of guardrail-to-bridge rail transitions revealed that many widely used designs do not meet current safety standards. As a result, the Federal Highway Administration (FHWA) requested that the Arizona Department of Transportation verify the safety performance of its standard transition designs. Three transition designs currently being used by ADOT were evaluated through a combined program of computer simulation and full-scale crash testing. The standard ADOT wood post transition, incorporating a channel rubrail and two different sizes of timber posts at a reduced post spacing near the bridge rail end, was found to be in compliance with National Cooperative Highway Research Program (NCHRP) Report 230 performance criteria. The standard ADOT steel post transition with channel rubrail was also found to be in compliance with NCHRP Report 230 requirements when impacted near the end of the bridge rail. However, the upstream end of the steel post transition required modification to eliminate deficiencies identified during testing. The modified design, which terminated the channel rubrail behind a W6x9 guardrail post, was successfully crash tested. A recent study on the performance of guardrail-to-bridge rail transitions revealed that many widely used designs do not meet current safety standards. As a result, the Federal Highway Administration (FHWA) requested that the Arizona Department of Transportation verify the safety performance of its standard transition designs. Three transition designs currently being used by ADOT were evaluated through a combined program of computer simulation and full-scale crash testing. The standard ADOT wood post transition, incorporating a channel rubrail and two different sizes of timber posts at a reduced post spacing near the bridge rail end, was found to be in compliance with National Cooperative Highway Research Program (NCHRP) Report 230 performance criteria. The standard ADOT steel post transition with channel rubrail was also found to be in compliance with NCHRP Report 230 requirements when impacted near the end of the bridge rail. However, the upstream end of the steel post transition required modification to eliminate deficiencies identified during testing. The modified design, which terminated the channel rubrail behind a W6x9 guardrail post, was successfully crash tested.
