Citation

McEnroe BM. Transp. Res. Rec. 1994; 1471: 18-23.

Copyright

(Copyright © 1994, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

On highway reconstruction projects the Kansas Department of Transportation now fits pipe culverts with end sections designed specifically for collision safety. These safety end sections are long and narrow with steel bars over the top openings. Scale models of 10 safety end sections were tested in a large water flume in the hydraulics laboratory at the University of Kansas. The objectives were to determine the relationship between headwater depth and discharge (the rating curve) under inlet control, the entrance-loss coefficient for full flow, and the susceptibility to blockage by debris for each design. The hydraulic characteristics of the safety end sections compare favorably with those of standard end sections. The inlet-control rating curves are described by a simple dimensionless relationship. Entrance-loss coefficients for full flow range from 0.65 to 0.85. At headwater depths greater than 1.4 times the pipe diameter, a concrete culvert with safety end sections will always flow full. At headwater depths greater than 2.0 times the pipe diameter, a corrugated steel culvert with safety end sections will always flow full. Most safety end sections are not particularly susceptible to blockage by floating debris. Debris seldom obstructs more than about one-fourth of the area of the top opening at high flows.

Record URL:
http://onlinepubs.trb.org/Onlinepubs/trr/1994/1471/1471-003.pdf

Language: en

Keywords

Embankments; Pipe; Performance; Drainage; Highway systems; Discharge (fluid mechanics); Culverts; Hydraulics; Model structures; Pipe fittings; Pipe flow; Reconstruction (structural)