Performance Problems and Structural Retrofit Analysis of Existing BCTs
Publication: Journal of Performance of Constructed Facilities
Volume 14, Issue 3
Abstract
Automobile accident reports and full-scale crash tests of existing breakaway cable terminals (BCTs) indicated their poor performance during end-on impacts. This paper presents results of a feasibility study, which was conducted to identify problems with existing BCTs. The nonlinear, explicit, dynamic finite-element code LS-DYNA was used in the investigation of BCT design problems. Several problems were identified in the past during the full-scale crash tests. These problems became clearly visible when computational mechanics analyses were used. In addition to severe vehicle damage, vehicular impact induced dangerous, large deceleration peaks and uncontrolled vehicle trajectories. Analysis of actual crash tests and LS-DYNA data led to the conclusion that the terminal is too stiff along its longitudinal direction and fails to smoothly control dissipation of the vehicle kinetic energy. Therefore, the major objective of the research was to soften the existing system by weakening the rail in strategically located areas. The paper describes the design retrofit process, which was continuously guided by computational mechanics analyses. Specific retrofit recommendations emerged at the end of this process and they are described in the paper. Full-scale crash tests are recommended to confirm expected benefits of the proposed retrofit.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Florida Department of Transportation (FDOT). ( 1994). “Roadway and traffic design standards.” Topic No. 625-010-003-c, Tallahassee, Fla.
2.
Gilbert, C., Kreja, I., and Wekezer, J. W. (1998). “Computer impact simulation in retrofit analysis of concrete bridge barriers.” Proc., 12th ASCE Engrg. Mech. Div. Conf., Reston, Va., 150–153.
3.
A guide to standardized highway barrier rail hardware. (1979). AASHTO-AARTBA-AGC Joint Cooperative Committee, Subcommittee in New Highway Materials, Task Force 13, Washington, D.C.
4.
Kimball, Jr., C. E., Bronstad, M. E., and Meczkowski, L. (1982). “Evaluation of guardrail breakaway cable terminals.” Rep. No. FHWA-RD-82-057, Federal Highway Administration, Washington, D.C.
5.
LS-DYNA keyword user's manual. Nonlinear dynamic analysis of structures in three dimensions. (1999). Livermore Software Technology Corp., Livermore, Calif.
6.
“Public finite element model archive, vehicle models, C-1500/2500 truck models, C-2500 model reduced version 7.” (1997). FHWA/NHTSA National Crash Analysis Center, Washington, D.C., 〈www.ncac.gwu.edu〉.
7.
Ray, M. H. (1995). “The use of finite element analysis in roadside hardware design.” Workshop on Important Issues for Improving Roadside Safety, Federal Highway Administration, Washington, D.C.
8.
Ray, M. H., and Patzner, G. S. (1997). “A finite element model of the modified eccentric loader breakaway cable terminal (MELT).” FHWA Vehicle Crash Anal., Conf. Proc. Publ. No. FHWA-RD-96-212, Federal Highway Administration, Washington, D.C., 33–53.
9.
Reid, J. D., Sicking, D. L., and Paulsen, G. W. (1996). “Design and analysis of approach terminal sections using simulation.”J. Transp. Engrg., ASCE, 122(5), 399–405.
10.
Ross, H. E., Sicking, D. L., Zimmer, R. A., and Michie, J. D. (1993). “Recommended procedures for the safety performance evaluation of highway features.” Rep. 350, Nat. Cooperative Hwy. Res. Program, National Research Council, Washington, D.C.
11.
Sicking, D. L. ( 1995). “Applications of simulation in design and analysis of roadside safety features. Roadside safety issues.” Transp. Res. Circular No., 435, Transportation Research Board, Washington, D.C., 63–70.
12.
“Strategies for improving roadside safety.” (1997). Res. Results Digest 220, Nat. Cooperative Hwy. Res. Program, National Research Council, Washington, D.C.
13.
“VHS video of WBCT-2.” (1982). VRTC-2b10.1, FHWA/NHTSA National Crash Analysis Center, George Washington University, Washington, D.C.
14.
Wekezer, J. W., Gilbert, C., and Kreja, I. (1996). “Conceptual analysis of an aesthetic bridge barrier.” Proj. No. WPI-0510750, Florida Department of Transportation, Tallahassee, Fla.
15.
Wekezer, J. W., Oskard, M. S., Logan, R. W., and Zywicz, E. (1993). “Vehicle impact simulation.”J. Transp. Engrg., ASCE, 119(4), 598–617.
16.
Wekezer, J. W., Ramaley, M., and Wuttrich, R. (1999). “Structural modifications of existing BCT Guardrail terminals.” Proj. No. WPI-0510652, Final Rep., Florida Department of Transportation, Tallahassee, Fla.
17.
Wekezer, J. W., Wuttrich, R., Ramaley, M., and Ray, M. (1998). “Design flaws and structural retrofit analysis of existing BCT terminals.” Proc., IJCrash '98, Int. J. Crashworthiness Conf., Dearborn, Mich., 531–542.
Information & Authors
Information
Published In
Journal of Performance of Constructed Facilities
Volume 14 • Issue 3 • August 2000
Pages: 118 - 125
History
Received: Nov 30, 1999
Published online: Aug 1, 2000
Published in print: Aug 2000
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.