DAMAGE ANALYSIS OF RIGID PVC PIPE AND STEEL PIPE FOR COMMUNICATION

Abstract

 Telecommunication conduits may suffer from earthquake and damage cables. Old type conduits were relatively likely to be damaged in past large earthquakes, and they still remains. There are two types of the old type conduits, rigid polyvinyl chloride pipes and steel pipes, which can have different characteristic of damage. In this paper, the damage rate was statistically analyzed from past earthquakes. As a result, there were a difference in seismic motion, span length, and ground tendency when comparing steel pipes and rigid polyvinyl chloride pipes. Also, when the damage location of each type was confirmed in the Kumamoto earthquake, both conduits were damaged in areas where liquefaction or fault displacement were occurred. Strain in the direction of the pipe axis was confirmed at locations where damage was concentrated only on steel conduits, and deformation at right angles to the pipe axis was confirmed at locations where damage was only on vinyl pipes. These do not contradict the statistical results.