Masters Theses


"Of all hydraulic structures, culverts are by far the most numerous. Lack of understanding of the functioning of culverts has resulted in many of them being implaced improperly and as a result, they function with less efficiency and at reduced capacity. Much has been written regarding the flow of water in open channels, culverts included, but little has been done regarding inlet conditions. It is necessary in the design of culverts, as with any other structure, that conditions which govern the operation of the structure be established. This paper is a study of the inlet conditions of a circular cross sectioned culvert with a sharp edged, flush mounted inlet.

The concept of critical flow was used to establish a control or critical section within the culvert model used. This concept of flow establishes the characteristics and location of the critical section. If certain conditions are met the critical section forms at the inlet, in this case measurement of entrance head loss and other inlet characteristics can be computed from this point.

It was established that outlet conditions control the flow rate of culverts placed at mild slopes, and the inlet controls the flow of culverts placed at critical or super critical slopes. An increase of slope past critical will not result in an increased flow rate. Only an increase in velocity within the barrel will result with a corresponding reduction in depth of flow.

Entrance losses are generally considered to have a value of one half of the velocity head within the barrel. Tests which were conducted resulted in computed head losses which proved this to be a reasonable value for inlets such as the one employed in the model.

An efficiency rating was established, which can be applied to any inlet configuration. The model tested had an efficiency rating of approximately .88 and is probably one of the least efficient designs employed in practice. Further studies should be made which would establish the most efficient inlet configuration for standard culvert sections employed in practice"--Abstract, pages 5-6.


Muir, Clifford D.

Committee Member(s)

Kerr, Richard H., 1907-1980
Gevecker, Vernon A. C., 1909-1992
Carlton, E. W.


Civil, Architectural and Environmental Engineering

Degree Name

M.S. in Civil Engineering


Missouri School of Mines and Metallurgy

Publication Date



47 pages

Note about bibliography

Includes bibliographical references (page 46).


© 1960 Luke Lea Callaway, Jr., All rights reserved.

Document Type

Thesis - Open Access

File Type




Subject Headings

Hydraulic structures
Slopes (Soil mechanics)

Thesis Number

T 1262

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