THE STRUCTURAL DESIGN OF STEEL CASING PIPES BORED BENEATH RAILROADS AND HIGHWAYS

A METHOD IS PRESENTED FOR THE STRUCTURAL DESIGN OF SMOOTH STEEL CASING PIPES WHICH ARE INSTALLED BY BORING BENEATH RAILROADS AND HIGHWAYS. THE INSTALLATION AND OBSERVATION OF 5 EXPERIMENTAL CASING PIPES UNDER 3 MAINLINE RAILROADS AT SEVERAL LOCATIONS WERE CONDUCTED. SOME MEASUREMENTS OF STRAINS IN THE PIPE WALLS UNDER PASSING TRAINS AND SETTLEMENTS OF THE PIPE INVERTS WERE MADE. DATA WERE COLLECTED FROM PIPELINE OPERATING COMPANIES RELATIVE TO DIAMETER MEASUREMENTS AND THE GENERAL TERMINAL CONDITION OF SOME CASING PIPES WHICH HAD BEEN IN SERVICE FOR A NUMBER OF YEARS. SUMMARIES ARE PRESENTED OF DIAMETER CHANGE MEASUREMENTS OF THE EXPERIMENTAL CASING PIPES, AND OF THE DIAMETER MEASUREMENTS OF ABANDONED CASINGS WHICH WERE INSTALLED BY BORING. RESEARCH INDICATED THAT BORED-IN-PLACE SMOOTH STEEL CASING PIPES ACT AS FLEXIBLE UNDERGROUND CONDUITS. FLEXIBLE PIPES FAIL BY EXCESSIVE DEFLECTION RATHER THAN BY RUPTURE OF THE PIPE WALL, AS IN THE CASE OF RIGID PIPES. A DEFLECTION FORMULA IS DERIVED INDICATING THE INFLUENCE ON DEFLECTION OF THE TRANSVERSE DISTRIBUTION OF THE UPWARD REACTION ON THE BOTTOM OF A BURIED PIPE. DESIGN OF FLEXIBLE PIPES ON THE BASIS OF A MAXIMUM DEFLECTION OF 3% OF THE DIAMETER IS SUGGESTED. CASING PIPES UNDER HIGHWAYS MAY BE DESIGNED IN THE SAME MANNER AS OUTLINED FOR RAILROADS.

• Supplemental Notes:
  • Special RepT, 33 PP, 9 FIG, 5 TAB
• Corporate Authors:

  Iowa State University, Ames

  2711 South Loop Drive
  Suite 4700
  Ames, IA  United States  50010-8664
• Authors:
  • Spangler, M G
• Publication Date: 1967-10

Subject/Index Terms

• TRT Terms: Boring; Building; Conduits; Data collection; Deflection; Diameter; Facilities; Flexible structures; Highways; Installation; Railroads; Smoothness; Steel pipe; Strain measurement; Structural design
• Old TRIS Terms: Casing /process/; Flexible conduits
• Subject Areas: Construction; Highways; Maintenance and Preservation; Operations and Traffic Management; Railroads;

Filing Info

• Accession Number: 00216172
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 30 1994 12:00AM