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Diagnosing the safety of fiberglass reinforced plastic mortal pipe by measuring the strain

Updated:July 13, 2017 (Thursday)

Prevent leakage of agricultural water pipelines in advance

An efficient method for diagnosing the safety of fiberglass reinforced plastic mortar pipe (FRPM pipe), which is widely used for pipeline of agricultural water, has been developed by measuring the strain on the pipe. This method allows quantitative diagnosis of the safety against leakage of agricultural water pipelines due to extensive damage. In addition, it also facilitates identification of locally deformed sections of the pipe that have been missed out even before the occurrence of cracking and water leakage.

Overview

  1. The NARO Institute for Rural Engineering, in collaboration with Ibaraki University, Kurimoto, Ltd. and Sekisui Chemical Co., Ltd., has successfully developed a method to determine the safety of FRPM pipes embedded in the ground as pipeline for agricultural water by measuring the strain on the pipes.
  2. The FRPM pipe embedded in the ground is normally deformed under pressure (earth pressure) from the soil surrounding the pipe. Until now, safety diagnosis is performed by measuring the degree of deformation of the whole pipe (deflection ratio). However, when the load is concentrated on a section of the pipe, it is impossible to accurately diagnose the safety with only the deflection ratio since it may be deformed locally and lead to cracks.
  3. A method to measure the local deformation and diagnose the safety of FRPM pipes have been developed. The radius of curvature of the FRPM pipe is used to calculate the strain of the pipe. Safety can be quantitatively diagnosed from the magnitude of distortion using a diagnostic chart. This method also allows the discovery of locally deformed dangerous sections of the pipe well before the water leakage.
  4. Manuals on this diagnostic method can be downloaded from the NARO website (in Japanese only). http://www.naro.affrc.go.jp/publicity_report/pub2016_or_later/pamphlet/tech-pamph/076137.html

Reference Information









For Inquiries

Dr. Tokuji YAMAMOTO
Director-General, Institute for Rural Engineering, NARO

Dr. Mitsuru ARIYOSHI
Principal Researcher, Soil Mechanics Unit
Division of Facilities and Geotechnical Engineering

Dr. Kazuko ENDO
Communications Planner, Institute for Rural Engineering, NARO

Contact: http://www.naro.affrc.go.jp/english/inquiry/index.html

Corporate Number 7050005005207