Retrospective Evaluation of Cured-in-Place Pipe - (NEPIS)(EPA ...

Figure 5-10. Profile Plotting with LVDT Rotating on the Inner Circumference:
Close Up (Left) and Complete View (Right)
Profiling was performed before and after the buckling test. The profile plotter was not used during the
test due to the risk of water leakage and/or sudden failure that might damage the LVDT.
Figure 5-11 compares the pre-buckling and post-buckling profile plots. From the pre-buckling profile
plot, it can be seen that the liner did not follow a perfect circular shape. The liner had several
irregularities that probably matched irregularities in the original host pipe with the largest excursion
(nearly a quarter inch outwards) from a circular shape occurring at the invert of the liner. The ovality of
the liner calculated in accordance with ASTM F1216 was 7.4%. It should be noted that for the buckling
test (described in Section 5.1.15), the liner was inserted and sealed within a circular steel pipe.
Figure 5-11. Profile Plot of Steel Host Pipe and Liner Before and After the Buckling
Test (Columbus 8-in. Liner)
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