BEHAVIOR OF LINER APPLIED TO AGRICULTURAL PIPELINES UNDER INTERNAL WATER PRESSURE AND EFFECT OF FILLING THE ANNULAR SPACE

Abstract

Numerous liners applied to agricultural pipelines are subjected to internal water pressure. Previous studies on liners focus on their behavior when subjected to external pressure, and the detailed behavior of liners subjected to internal water pressure has not been clarified. Thus, experiments were conducted by applying internal water pressure on a liner (φ1,000 mm) to investigate the influence of a bend, which is a feature of agricultural pipelines, the presence or absence of filling material in a gap between the liner and existing pipe, and deteriorated pipe on the behavior of a liner under internal water pressure. The results reveal that the longitudinal strain of a bend is much greater than that of a straight pipe.Moreover, filling the space decreases the circumferential strain in a straight pipe and longitudinal strains at a bend, and only the liner sustains the internal water pressure when the existing pipe has no strength.