Page 117 - Buried Pipe Design

High, 95% Proctor, 70% relative density 0 1000 2000 3000 3000 ±0.5

for degree of compaction of bedding, lb/in 2 Moderate, 85–95% Proctor, 40–70% relative density No data available. Consult a competent soils engineer; otherwise, use E′ 400 1000 2000 3000 ±1

(for Initial Flexible Pipe Deflection) E′ Slight,
85% Proctor,
40% relative density 200 400 1000 3000 ±2 NOTE: Values applicable only for fills less than 50 ft (15 m). Table does not include any safety factor. For use in predicting initial deflections only, appro- priate deflection lag factor mu

Average Values of Modulus of Soil Reaction E′
Dumped 50 100 200 1000 ±2 ‡ Or any borderline soil beginning with one of these symbols (i.e., GM-GC, GC-SC). § For ±1 percent accuracy and predicted deflection of 3 percent, actual deflection would be between 2 and 4 percent. January 1977, pp. 33–43. Reprinted with permission

Soil type-pipe bedding material (Unified Soil Classification System ∗ ) 50) † Soils with medium to high plasticity 50)
Soils with medium to no plasticity with less than 25% coarse-grained particles 50)
Soils with medium to no plasticity with more than 25% coarse-grained particles Co

TABLE 3.4 Fine-grained soils (LL CH, MH, CH-MH Fine-grained soils (LL CL, ML, ML-CL Fine-grained soils (LL CL, ML, ML-CL GW, GP, SW, SP ‡ Crushed rock † LL E′ SOURCE: Div.,

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