# Investigation of Earthquake-Induced Pipe Damage in Liquefiable Soils
## 4 Evaluation of Pipeline Damage Caused by Earthquake in the Iskenderun Region  
After the earthquakes on 6 February, damage in the infrastructure facilities and pipelines in the region due to liquefaction were detected. Figure 7 illustrates the layout of the sewage and stormwater pipelines, as well as pumping stations in Iskenderun, Hatay. The sewage and stormwater pipes have diameters ranging from \(\mathcal{O}\) 300 mm to \(\mathcal{O}\) 1200 mm. The stormwater pipelines on Ataturk Boulevard start from \(\mathcal{O}\) 600 mm and reach up to \(\mathcal{O}\) 800 mm, finally discharging at a diameter of \(\mathcal{O}\) 1200 mm. After the earthquakes, the State Hydraulic Works planned to repair these damaged pipelines and pumping stations. In Figure 8a, a manhole cover and manhole shaft on Ataturk Boulevard that were damaged due to the earthquake are shown. In Figure 8b,c, the area affected by the damage in the stormwater and sewage pipes on the same boulevard is seen. As can be seen in Figure 8c, the pipes in this area were broken due to the occurrence of settlements caused by liquefaction after the earthquake, and as the existing inclination was insufficient, obstructed water flow caused blockages and ponding. The U-shaped French stormwater channel shown in Figure 7 and its associated pumping station, Shelter Sewer pumping station no.1, and Maternity House stormwater pumping station 2 were subjected to uplift reaching 30-40 cm in the caisson foundations of the structures (Figure 9a,b). Damage occurred in the pipes inside these structures (Figure 9c). In Figure 10a, a photograph taken after the earthquake in the Iskenderun port area shows settlement reaching 1 m, resulting from liquefaction. Figure 10b shows the approximately 0.70 m uplift of the shallow buried pipe in Cay District, covering the rear part of Ataturk Boulevard. Figure 6: Comparison of pipe displacements at the pipe edge with test results [22; 23]. Figure 8: **(a)** Collapsed manhole (36.55086\({}^{\circ}\) N, 36.17325\({}^{\circ}\) E); **(b)** pipe damage (36.59055\({}^{\circ}\) N, 36.17375\({}^{\circ}\) E); **(c)** flooded street after liquefaction (36.590715\({}^{\circ}\) N, 36.174906\({}^{\circ}\) E), Atatürk Boulevard/Iskenderun/Hatay, one year after the earthquake. Figure 7: Concrete pipe damage caused by seismic soil liquefaction around Atatürk Boulevard in Yenisehir District, Savas District, and Cay District, Iskenderun [57]. After the earthquake, it was stated in the Post-Earthquake Activity Report prepared by the Ministry of Agriculture and Forestry--State Hydraulic Works (DSI) (dated 6 February-28 February 2023) that water was supplied to the city center of Hatay province from Harbiye Springs and Buyuk Karacay Dam. For this purpose, two steel flanges of \(\mathcal{O}\) 1100 mm, 102 m of DN 800 cast concrete pipe, and three pieces of DN800 sliding sleeves were used to repair the transmission line. In order to rebuild and reroute a 750-m transmission line supplying water to Iskenderun city center, \(\mathcal{O}\) 1500 cast iron pipes were used [59]. The damaged water supply line was observed at three different locations in Ataturk Boulevard (Work Area 2), where ductile steel pipes were located, as indicated in Figure 11a-c. Pipes \(\mathcal{O}\) 100 mm to \(\mathcal{O}\) 1000 mm in diameter suffered broken joints due to uplift caused by liquefaction. Figure 10: Settlements and pipe damage caused by seismic soil liquefaction (**a**) Iskenderun Ports Region/Hatay (36.59991\({}^{\circ}\) N, 36.19274\({}^{\circ}\) E) [58]; (**b**) Cay district, Iskenderun, Hatay (36.59038\({}^{\circ}\) N, 36.17893\({}^{\circ}\) E) [58]. Figure 9: (**a**) French Channel stormwater pumping station (36.590769\({}^{\circ}\)N, 36.175932\({}^{\circ}\)E) [57]; (**b**) Barmak sewer booster station no. 1 (36.590769\({}^{\circ}\) N, 36.175932\({}^{\circ}\) E) [57]; (**c**) Dogum evi rainwater booster station no. 2 (36.594583\({}^{\circ}\) N, 36.163268\({}^{\circ}\) E) [57].