The Role of Soil Behavior on Damage Caused by the Dinar Earthquake (Southwestern Turkey) of October 1, 1995

The Dinar earthquake (M_L = 6.0) took place in southwestern Turkey on October 1, 1995, and caused extensive damage to buildings in the city of Dinar. Soil liquefaction and lateral-spreading types of ground failure developed in the vicinity of Dinar. In order to investigate the possible contribution to the damage to buildings by site amplification, both the practical method of calculating the natural period of soils and site response analyses were performed. Geotechnical data from borehole records, and hypothetically assigned shear wave velocities to the soil layers were combined into the computer model SHAKE91 to compute the predominant period of the soil columns at four selected locations. The results of site response analyses indicate that the predominant periods of those locations are far beyond that of buildings in Dinar. Thus, it was concluded that the heavy damage to buildings associated with the recent earthquake is attributed largely to the use of improper material and poor design. The relatively long duration of earthquake shaking intensified the damage to the poorly constructed buildings.