PSI - Issue 20

A.A. Antonov et al. / Procedia Structural Integrity 20 (2019) 270–277

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A.A. Antonov et al. / Structural Integrity Procedia 00 (2019) 000–000

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The actual depth of the pipeline axis was measured with a probe at 2-3 arbitrary control points in the inspected area to check the accuracy of the measurements performed by the line locator. The complex instrumental examination of the state of the underwater crossing of TGPL across the Lena River with the help of the OKO-2 GPR and the Hydra-500E SSS allows detecting denuded sections of the inverted siphon and determining its sagging height. An example of the information obtained is shown in Figure 3a, b.

Fig. 3. Radarograms obtained by the OKO-2M GPR (a); Bottom fragment, arrows indicate the denuded section of the pipeline (b).

The planned-high-altitude position of the underwater gas pipeline in the floodplain part is determined with the help of the RD-8000 locator and the tacheometer, and its change over time is monitored. For example, figure 4 demonstrates the depth of the section of the line-I of the underwater crossing of TGPL on Uluu Aryy island.

Fig. 4. Section of the line-I of the underwater gas pipeline on Uluu Aryy island of Hatassy village.