IMPACT RESPONSE OF OVERHEAD SIGN BRIDGES MOUNTED ON BREAKAWAY SUPPORTS
MOST MODERN ROADWAYS EMPLOY OVERHEAD SIGN BRIDGES TO RELAY INFORMATION TO THE MOTORING PUBLIC EFFICIENTLY. COLLISIONS WITH THESE MASSIVE STRUCTURES HAVE CAUSED SERIOUS INJURIES AND FATALITIES AS CURRENT INSTALLATIONS DO NOT EMPLOY SAFETY FEATURES THAT LIMIT IMPACT FORCES INCURRED DURING A COLLISION. THE GENERAL DESIGN CONSIDERATIONS AND THE RESULTS OF THE MATHEMATICAL SIMULATION OF VEHICLE COLLISION WITH OVERHEAD SIGN BRIDGES MOUNTED ON BREAKAWAY SUPPORTS ARE PRESENTED. THE RESULTS WERE OBTAINED THROUGH THE USE OF A MATHEMATICAL MODEL VERIFIED BY SEVEN FULL- SCALE CRASH TESTS. A COMPARISON OF MODEL AND TEST RESULTS IS SHOWN AND INDICATES GOOD AGREEMENT. THE STUDY WAS PERFORMED ON A HIGH-SPEED ELECTRONIC COMPUTER. THE FINDINGS AND THE RESULTS OF THE CRASH TESTS ARE: (1) THE APPLICATION OF THE BREAKAWAY CONCEPT TO THE SUPPORTS OF AN OVERHEAD SIGN BRIDGE IS FEASIBLE. (2) THE PROTOTYPE TRUSS POSSESSED THE ABILITY TO WITHSTAND THE TORSIONAL LOADS IMPARTED TO IT BY THE ROTATING SUPPORT, AND THE STRUCTURE AS A WHOLE REMAINED STABLE UNDER THE IMPACT FORCES. (3) VEHICLE-VELOCITY CHANGES AND DECELERATION RATES INCREASE AS BREAKAWAY BASE AND UPPE-SHEAR CONNECTION RESISTANCE INCREASE. (4) OCCUPANTS OF SMALL TO MEDIUM-SIZE VEHICLES COULD POSSIBLY SUFFER INJURY IN A COLLISION WITH THE PROTOTYPE SUPPORT. (5) LARGER VEHICLES WERE NOT SEVERELY DAMAGED IN COLLISIONS WITH THE PROTOTYPE SUPPORT. /AUTHOR/
- Record URL:
-
Availability:
- Find a library where document is available. Order URL: http://worldcat.org/isbn/0309019575
-
Supplemental Notes:
- Sponsored by Committee on Traffic Safety Barriers and Sign, Signal and Lighting Supports and presented at the 50th Annual Meeting. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
-
Authors:
- MARTINEZ, J E
- Olson, R M
- Post, E R
-
Conference:
- 50th Annual Meeting of the Highway Research Board
- Location: Washington District of Columbia, United States
- Date: 1971-1-18 to 1971-1-22
- Publication Date: 1971
Media Info
- Media Type: Print
- Features: Figures; References; Tables;
- Pagination: pp 23-34
- Monograph Title: Design of Sign Supports and Structures
-
Serial:
- Highway Research Record
- Issue Number: 346
- Publisher: Highway Research Board
Subject/Index Terms
- TRT Terms: Breakaway supports; Bridges; Crash tests; Crashes; Design; Information processing; Injuries; Mathematical models; Overhead traffic signs; Prototypes; Simulation; Structural supports; Testing; Traffic signs
- Old TRIS Terms: Supports
- Subject Areas: Bridges and other structures; Design; Highways; Research; Safety and Human Factors;
Filing Info
- Accession Number: 00203580
- Record Type: Publication
- ISBN: 0309019575
- Files: TRIS, TRB
- Created Date: Sep 13 1971 12:00AM