Page 264 - Buried Pipe Design
P. 264
Pressure, lb/in 2
Cover
Backfill 400 300 200 100 50 depth, Remarks Rerounding coefficient R ft 0.25 0.47 0.98 1.04 12.8 Loose 0.16 0.45 0.89 0.90 dry sand 1961 0.18 0.29 0.44 0.67 0.87 8.0 Native 1963 0.23 0.38 0.60 0.90 0.96 soil 90% Proctor (initial) 0.43 @ 350 lb/in
Pipe mat. FRP Ductile iron FRP
Rerounding Coefficient Pipe stiffness, lb/in 2 D 30.5 48 247.0 36 97.3 35
TABLE 4.12 /D Ref. 3.17 8 2.0 19 2.2 7
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