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

Figure 5-8. Average Thickness at Different Locations (Columbus 8-in. Liner)
5.2.10 Specific Gravity and Porosity. Measurements of density and porosity of a sample from this
liner specimen were made by TTC and by Micrometrics Analytical Services. The TTC result for specific
gravity (based on testing of 7 samples) was 1.11 ± 0.94. In the Micrometrics testing (using mercury
penetration for the porosity determination), the bulk density (at 0.54 psia) was 1.1739 g/mL, the apparent
(skeletal) density was 1.2782 g/mL, and the porosity was 8.163%. The full test report is provided in
Appendix C and the specific gravity results across all samples are compared and discussed in Section 6.
5.2.11 Ovality. A profile plotter (Figure 5-9) developed at TTC was used to obtain a profile of the
interior of the liner to be tested for buckling under external pressure. This profiling system is equipped
with an LVDT rotating a full circle in one and one-half minutes. The voltage reading changes as the tip
of the LVDT moves axially and those readings were collected using an HP 34970A DAQ. Later, the data
was processed to obtain the actual profile of the liner’s inside circumference. Before profiling, the pipe
and profile plotter were positioned horizontally (Figure 5-10) and aligned. Figure 5-11 shows the plotted
circumferential profile of the liner.
Figure 5-9. Electronic Level Used to Position Horizontally the Pipe (Left) and the
Profile Plotter (Right)
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