Microwave Time-Domain Analysis for Non-Destructive Inspection of FRPM Pipelines Using Electro-Optic Sensor

We have proposed a new non-destructive inspection method for buried FRPM (Fiberglass Reinforced Plastic Mortar) pipelines using microwave guided-modes, which can propagate along FRPM pipe walls with relatively low loss. In addition, the microwave guided-mode signal can be reflected by foreign objects on the outer surface of the buried FRPM pipeline or cracks in the pipe wall, which brings us to have a powerful technique for pipeline non-destructive inspection. In this paper, we report microwave time-domain analysis for easy-to-use non-destructive inspection of FRPM pipelines using EO (Electro-Optic) sensors. We believe that it can be used for non-destructive inspection of buried FRPM pipelines.

I. Introduction

As Fiberglass Reinforced Plastic Mortar (FRPM) pipes are mechanically and chemically stable, FRPM pipelines are widely used for the applications to many infrastructures. For example, the total length of underground FRPM pipelines for agriculture water supply is about 50,000 kilometers in Japan [1] . However, at present, there is no practiced method for non-destructive inspection of the FRPM buried pipelines under-ground. Therefore, there is a need for a method to perform inspection and diagnosis of the buried pipeline non-destructively.