MODEL STUDIES OF TAPERED INLETS FOR BOX CULVERTS, WITH DISCUSSIONS
THE OBJECTIVES OF THE EXPERIMENTS WERE: (1) CLARIFICATION OF THE THEORY OF OPERATION OF BOX CULVERTS, AND (2) MODIFICATION OF THE DESIGN OF THE OREGON STATE HIGHWAY STANDARD INLET IN ORDER TO INCREASE THE OVERALL EFFECTIVENESS OF THE CULVERT AS A DRAINAGE STRUCTURE. TEST DATA WERE TAKEN FROM A 1:12 SCALE MODEL OF A 4' X 4' BOX CULVERT 82 FT. LONG. THIS MODEL WAS PROVIDED WITH A TRAPEZOIDAL APPROACH CHANNEL AND A SECTION OF EMBANKMENT SLOPE WITH MEANS FOR INSTALLING DIFFERENT TYPES OF INLETS WITHOUT MAJOR CHANGES IN THE MODEL. THREE BASIC TYPES OF INLETS WERE TESTED: THE OREGON STATE HIGHWAY COMMISSION STANDARD INLET WITH NO FLARE OR TAPER, AN INLET WITH A TAPER IN THE SIDES AND TOP OF 1 TO 10, AND AN INLET DESIGNED PRIMARILY FOR OPERATION UNDER ENTRANCE CONTROL. THE INITIAL TESTING CONSISTED OF THREE GENERAL TYPES OF COMPARISONS: (1) ANALYSIS OF THE OPERATION OF ALL THREE INLETS IN NONSUBMERGED STATES, (2) OPERATION OF THE STANDARD INLET AS A SLUICE GATE, AND (3) FULL-FLOW OPERATION OF THE STANDARD AND TAPERED INLETS. TEST RESULTS INDICATE THAT THE STANDARD INLET FLOWING AS A SLUICE CAN BE TREATED WITH EXISTING ORIFICE THEORY AND THAT EXISTING THEORY REGARDING PIPE FLOW CAN BE USED FOR THE FULL-FLOW CONDITIONS OF THE TAPERED INLET. THE CONCLUSIONS WERE: (1) A SIGNIFICANT SAVING OF MATERIALS COULD RESULT FROM DESIGNING CULVERTS ON STEEP GRADES TO FLOW FULL, (2) THE FORMATION OF A TAPERED INLET BY THE EXTENSION OF THE TOP SLAB AND WING WALLS WOULD BE A PRACTICAL SOLUTION TO THE PROBLEM OF ASSURING FULL FLOW, AND (3) BY PROPER APPLICATION EXISTING THEORY IS ADEQUATE FOR THE DESIGN OF CULVERTS ON STEEP GRADES. /AUTHOR/
- Record URL:
-
Supplemental Notes:
- Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
-
Corporate Authors:
Highway Research Board (HRB)
Washington, DC -
Authors:
- Shoemaker Jr, Roy H
- Clayton, Leslie A
-
Discussers:
- Ree, W O
- Izzard, Carl F
-
Conference:
- 32nd Annual Conference of the Highway Research Board
- Location: Washington District of Columbia, United States
- Date: 1953-1-13 to 1953-1-16
- Publication Date: 1953
Media Info
- Media Type: Digital/other
- Features: Figures;
- Pagination: 52p
- Monograph Title: Culvert hydraulics
-
Serial:
- Highway Research Board Research Reports
- Issue Number: 15B
- Publisher: Highway Research Board
Subject/Index Terms
- TRT Terms: Box culverts; Culvert inlets; Design; Drainage; Drainage structures; Mathematical models; Slopes; Sluices; Tapered traffic lanes
- Uncontrolled Terms: Inlets; Models
- Old TRIS Terms: Drainage rate; Taper
- Subject Areas: Design; Highways; Hydraulics and Hydrology;
Filing Info
- Accession Number: 00204415
- Record Type: Publication
- Files: TRIS, TRB
- Created Date: May 22 1972 12:00AM