OPTIMUM DESIGN METHODOLOGY FOR ELEVATED TRANSIT STRUCTURES. FINAL REPORT
The need to design efficient supporting structures with minimal vibration response for use in modern transit vehicle systems generated this study. The methodologies presented herein purport to aid the designer in producing advanced-concept, minimum cost, urban transit structures with high strength to weight ratios, which also have aesthetic appeal and afford a high degree of ride comfort. This report is organized into 4 sections. In Chapter 1, optimal pier spacings for uniform spans are predicted; span inertia effects are included. Calculated optimal span responses to constant loads at constant speed, verified experimentally, show a peak stress reduction of up to 30 percent, compared to simple spans end-to-end. In Chapter 2, similar results are found for uniform, continuous, inertialess spans, where the transit mass is much larger than the span mass. In Chapter 3, the effects on span efficiency of the nonuniform stiffness and unit mass parameters are investigated; extensive use is made of computer graphics to illustrate the design methodology. In Chapter 4, the Duke University transit system is the reference case used for alternative design studies, where up to 40 percent reductions in concrete weight are possible. The author concludes that the most efficient designs are continuous span configurations with a minimum number of pier supports, properly spaced so that balanced stresses are achieved. This report contains conclusions, a list of references, and numerous charts depicting various span and guideway configurations.
- See also Executive Summary, PB82-126988.
Duke UniversityDepartment of Civil Engineering
Durham, NC United States 27706
Urban Mass Transportation Administration400 7th Street, SW
Washington, DC United States 20590
- Wilson, J F
- Publication Date: 1981-10
- Pagination: 146 p.
- TRT Terms: Alternatives analysis; Bending moments; Computer graphics; Computer programming; Dynamic loads; Dynamic structural analysis; Elevated guideways; Methodology; Railroad bridges; Rapid transit; Structural design
- Uncontrolled Terms: Dynamic response; Forced vibration
- Old TRIS Terms: Rapid transit railways
- Subject Areas: Construction; Operations and Traffic Management; Public Transportation; I70: Traffic and Transport;
- Accession Number: 00346706
- Record Type: Publication
- Source Agency: National Technical Information Service
- Report/Paper Numbers: UMTA-NC-11-0010-81-2Final Rpt.
- Files: NTIS, TRIS, USDOT
- Created Date: Jan 29 1982 12:00AM