PSI - Issue 78

Fabio Micozzi et al. / Procedia Structural Integrity 78 (2026) 1205–1212

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house closest to the wall (Building 1, see in Fig. 8d) was directly on the fault trace. This structure experienced a clear counterclockwise rotation, highlighted by the opening of a big gap on the back right side (Fig. 8e and f). In this location a new opening on the back retaining wall of 160 cm was created by the fault strike. However, the structure experienced only the collapse of the detached lightweight steel roof extension (probably added to the original construction, see Building 2 in Fig. 8c) and only few damages to the external walls. From Fig. 8 it is possible to see that despite the opening of the huge gap on the foundation level, no damages are visible on the external infill walls. It is possible to deduce that also in this case the shallow foundation floated on the fault strike resulting simply in a rigid rotation of the structure.

(a)

(b)

(c)

2.5m

wall

Building 2

Building 1

(d)

(e)

(f)

Fig. 8. Two floor concrete house (POI_9, 37.493744, 37.072907, 0 km from the fault, 2.5 m measured directly on the site)

The last case of is the Tektu ğ Erkenek hes hydraulic power plant. According to the local workers met during the survey the structure was designed to withstand an earthquake of 9 Mw of magnitude. Unlike the previous cases, this structure was embedded in stiff soil. Consequently, the strike of the fault resulted in a direct shear deformation of the concrete box. The result is the complete shear failure at the base of the walls on the longer sides, maybe amplified by the soil pressure. These observations underscore the vulnerability of underground structures in fault-affected zones, where there is no possible engineering solution to sustain the force related to the fault strike in stiff soil.