Crunkhorn, Smith, Whiter, Mulheron
Rehabilitation # 2001 Munich
Cast iron pipes have been loaded to failure using a four point bending geometry under displacement-controlled loading. Specimens were tested with various liner configurations : unlined, epoxy resin lined or lined with one of two interactive (semi-structural) liners. Some of the pipes also had a circumferential notch machined into the surface, in order to simulate the effect of corrosion. The results indicate that the interactive liners are able to survive catastrophic circumferential (ring) failures of the type caused by such loading. Simple bending theory enabled the stress/strain response of the cast iron to be determined using strain gauges, and the failure strengths of the pipes to be found. The failure strengths showed variability, not unexpectedly for a nominally brittle material. There was no apparent effect of the liners on the strength values for either the un-notched pipes or the notched pipes. There was a weak correlation between increasing notch depth and decreasing failure stress.
