Page 338 - Buried Pipe Design
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Steel and Ductile Iron Flexible Pipe Products 309
Figure 6.19 Vertical deflection for the three tests in silty-sand soil at various densities.
Tests on low stiffness ribbed steel pipe
Introduction. Tests were performed on a ribbed steel pipe which has
been designed for use in the small diameter drainage pipe market.
The pipe is a smooth bore, helically ribbed pipe with essentially closed
ribs. Pipes tested are 18-, 24-, and 30-in diameters. A total of 10 tests
were conducted. The tests were run at Utah State University in the
small soil load cell (see Figs. 6.20 and 6.21). The pipe properties are
as follows:
The Steel Sheet
Measured Modulus, Yield, lb/in 2 Tensile strength, lb/in 2
Gage thickness, in lb/in 2 Minimum Actual Minimum Actual
26 0.023 29.5 10 6 33,000 48,700 45,000 56,100
Description of pipes tested
1. The pipe is ribbed and is formed by helical winding with a lock-
seam.
2. The closed rib is 0.375 in tall for the 18- and 24-in pipes and 0.50-in
tall for the 30-in pipe. Three ribs are spaced over 5.43 in.
