UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 852 
Contribution from the Bureau of Public Roads 
Thos. H. MacDonald, Chief 
Washington, D. C. 
PROFESSIONAL PAPER 
October 28, 1920 
THE FLOW OF WATER IN CONCRETE PIPE. 
By Feed C. Sgobey, Senior Irrigation Engineer, with discussion by Kenneth Allen, 
Arthur S. Bent, F. C. Finkle, Allen Hazen, J. B. Lippincott, and H. D. 
Newell. 
CONTENTS. 
Introduction 1 
Nomenclature- 2 
T ypes of pipe 3 
Part 1. Flow of water in pressure pipes 5 
Formulas for flow of water in concrete pres- 
sure pipes 5 
Opinions of engineers regarding the carrying 
capacity of concrete pipe 9 
Necessary field data for deter mini ng the re- 
tardation elements of various formulas. . . 12 
Scope of the experiments 13 
Equipment and methods employed for col- 
lecting and interpreting field data 13 
Elements of experiments for the determina- 
tion of the friction losses in concrete pipes . 20 
Page. 
Description of pipes 25 
Analysis of experimental data 45 
Effect of age upon carrying capacity 49 
Capacity of concrete pipes 51 
Estimate diagrams and tables; solution of typical 
pipe problems 54 
Comparison of various formulas 62 
Capacity of concrete pipe compared with that of 
wood-stave, cast-iron, or riveted-steel pipe. . . 65 
Part 2. Flow of water in grade line pipes 66 
Descriptions of pipes 71 
Conclusions 74 
Acknowledgments. . „ 76 
Appendix = .....„ 77 
Discussion 92 
INTRODUCTION. 
Consequent to the general increase in use of concrete during the past 15 
years, it has been but natural that this material should be tried for 
pipe lines; and, although there are localities where poor construction 
has brought concrete pipe into disfavor, where properly made it is 
undoubtedly a success. For a long tim.3 concrete was thought 
adaptable to low heads only. Now it is used extensively in this 
country for heads exceeding even 100 feet, and in Europe lines have 
been constructed to withstand pressure heads of several hundred feet. 
Where the heads exceed more than 15 or 20 feet the pipe is, as a 
rule, reinforced with steel. 
The fact that it may be made at or near the place of use recom- 
mends this type of construction for irrigation or other pipes far 
removed from railway lines. In many cases the forms and cement 
Note. — This bulletin treats of the subject of flowing water in concrete pipes. It 
is based on field tests made on pipes in commercial operation. This publication is 
offered for use of engineers designing and measuring concrete pipes for irrigation, 
power, municipal, mining, or other purposes and for courts and attorneys at law 
interested in cases involving the carrying capacities of concrete pipes. 
164725°— 20— Bull. 852 1 
