# Investigation of Earthquake-Induced Pipe Damage in Liquefiable Soils
## 6 Conclusions  
In the article, the behavior of buried pipes during the 6 February 2023, Kahramanmaras Pazarcik earthquake was investigated through numerical analyses using the records of accelerometer stations 3115 and 3116 in Iskenderun, considering geological profiles in two areas with liquefaction potential. The effects of soil conditions and seismic acceleration on pipe behavior at the recorded station were determined. Liquefaction occurred in the coastal area, and the excess pore water pressure ratio (Ru value) reached 1. In the studied area, a vertical displacement of maximum 0.56 m was calculated when bedrock was shallow, whereas in areas where the bedrock lay at a considerable depth, the calculated displacements range from 0.56 m to 1.7 m. The field observations and damage records confirm the amounts of settlement calculated. Field observations revealed liquefaction-induced settlements ranging from 0.30 m to 1.50 m along the coastline. Figure 24: Total vertical displacements after earthquake motion. In Study Area 1, the effects of shallow and deep rock layers, pipe diameter, burial depths, and boundary conditions were investigated using records from accelerometer stations 3115 and 3116. A small amount of pipe uplift was calculated when there was a shallow rock layer. In shallow rock conditions, different burial depths (1D, 1.2D, and 1.5D) were tried, and increasing the burial depth reduced the amount of uplift. The absence of significant damage in the transmission line of the treatment plant under station 3116 supports the analysis results. When the rock layer was deep (station 3115 records), greater pipe uplift was calculated, indicating that boundary conditions influence the model to a greater extent. When the model boundaries were expanded, settlements around the pipe were reduced, and the obstructive effect of this behavior on pipe uplift diminished. It is concluded that in seismic analyses where significant displacements occur, increasing the model width is essential to reduce the misleading effect of boundary conditions on pipe behavior. Additionally, the increase in pipe diameter resulted in increased pipe uplift in the analyses. The analysis results and the observed damage at pipe joints due to liquefaction in coastal sections of the Sariseki spring water transmission line are consistent. The main cause of the significant pipe damage in this area was slope failures following the earthquake. In Study Area 2, the effect of pipe uplift in a thick alluvial layer was investigated using seismic records obtained from the soil layers at station 3115 (where the bedrock was deep). In the analyses, significant settlements occurred at a distance from the pipe. In the section where the pipe was located, however, the settlement amount decreased due to the uplift effect of the pipe. The flooding on Ataturk Boulevard due to damage inflicted on sewer and stormwater pipelines, caused by the occurrence of post-earthquake settlements governed by the thickness of the liquefied layer, validates the analysis results. The uplift observed in the caisson foundations of the stormwater and sewage pumping station on the coast supports the calculated uplift behavior in the region. The results of this study lead to the conclusion that the dynamic modeling of critical pipes in liquefaction-prone areas can support measures to prevent damage during earthquakes, by predicting seismic effects. This study covers the results obtained from numerical analyses performed utilizing actual specific ground and seismic data. Solution proposals can be generated by conducting numerical analyses for different ground conditions. Conceptualization, M.D. and H.K. ; methodology, M.D. and H.K. ; software, M.D. ; validation, M.D. and H.K. ; investigation, M.D. ; writing--original draft preparation, M.D. ; writing--review and editing, M.D. and H.K. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Not applicable based on AE's suggestion and this text does not include the ethics issues.