FIELD PERFORMANCE OF FLEXIBLE CULVERT PIPES

A total of 19 culverts were studied to evaluate their field performance. Measurements were made of the stiffness of the backfill soil, culvert deflection and culvert stress. A soil modulus measuring device was built and used to measure the Young's modulus of the soil. The results indicate that Young's modulus varies over a wide range from one site to another and also from one point to another at the same site. The range in measured Young's modulus is from 90 to 3280 psi. Culvert deflections were measured with a dial on a rotating arm which in turn is anchored to a cross brace. The cross brace is positioned inside culverts at sections where deflection measurements are to be made. About 40% of the culvert sections has deflections exceeding the design criterion of 5%. The maximum measured value is about 8% which is well below the value of 20% usually associated with bending failure. Culvert stresses measured by use of a stress-relief technique, indicate that stresses are close to the yield point at deflections of 5% or larger. However, the accuracy of the technique is poor due to large fluctuations in the measured residual stresses. The Iowa formula, widely used for calculation of culvert deflection, was used to calculate the modulus of passive soil resistance, from the measured deflections. Values of the modulus of passive soil resistance range from 300 to 3700 psi. The correlation between the modulus of passive soil resistance and Young's modulus is poor and is strongly infleunced by the stiffness of the culvert relative to the soil stiffness. /FHWA/

  • Supplemental Notes:
    • Sponsored by Ohio Department of Transportation. Prepared in cooperation with the Federal Highway Administration.
  • Corporate Authors:

    Ohio State University, Columbus

    Transplex, 2070 Neil Avenue
    Columbus, OH  USA  43210
  • Authors:
    • Wu, T H
  • Publication Date: 1977-12

Media Info

  • Pagination: 136 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00196057
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-RD-S0858 Final Rpt., FCP 45I2-132
  • Contract Numbers: State Job 14261(0)
  • Files: TRIS, USDOT
  • Created Date: Sep 15 1979 12:00AM