Research Article

Influence of Backfill Compaction on Mechanical Characteristics of High-Density Polyethylene Double-Wall Corrugated Pipelines

Figure 17

(a) Location of loose backfill; the circumference strain nephogram of the (b) interior wall and (c) exterior wall when the left sides of Lay 01 and Lay 02 were loose.
(a)
(b)
(c)