A site survey of damaged RC buildings in İzmir after the Aegean sea earthquake on October 30, 2020

Abstract

An earthquake with a magnitude of Mw = 6.6 and a depth of approximately 16.5 km occurred on 30 October 2020 off the cost of Samos, a Greek island 35 km southwest of Seferihisar, a town in İzmir. The earthquake caused several collapses and severe structural damage in approximately 6,000 buildings, specifically in the Bayraklı District in İzmir Bay. This paper presents the observations and findings of a technical team that visited the earthquake-affected areas immediately after an earthquake. Eleven partially or fully collapsed buildings and several severely damaged reinforced concrete buildings were investigated. Based on the site observations, we observed that almost all of the collapsed or severely damaged reinforced concrete buildings in the region were built between 1975 and 2000. Site observations also confirmed that the construction of these collapsed or damaged buildings did not conform to the requirements outlined in the Turkish Earthquake Codes used at the time. The failures and severe damage to buildings in earthquake-affected areas are primarily related to inadequate reinforcement configuration, poor material quality, the absence of geotechnical studies, and framing problems related to their lateral load-carrying systems. Therefore, it is recommended that all the buildings located in and around İzmir Bay, particularly those built between 1975 and 2000, be structurally evaluated to prevent any further loss of life and property during future earthquakes.

Investigation of RC Buildings after 6 February 2023, Kahramanmaraş, Türkiye Earthquakes

“…The basic issues related to the extensive damage and collapse of RC buildings in the Kahramanmaraş earthquakes are explained in this section as shown in Figure 20. It should be noted that the issues listed above are common problems encountered during earthquake site investigations here, and elsewhere, in Türkiye [1,44,45]. The damage and failure of many RC buildings can be explained using these basic problems, among others.…”

“…Payments were also made to the pool and the inspecting company was paid from this pool. Therefore, it can be concluded that the inspection services of construction work in Türkiye became more reliable after 2019 [1,45].…”

“…Sufficient development lengths shall be provided for the beam longitudinal reinforcement at the beam-column connections to satisfy the integrity of the joints, especially external ones. Since the column width is limited to satisfy this development length at the outside joints, the ends of longitudinal reinforcement of beam shall be bent 90° to avoid It should be noted that the issues listed above are common problems encountered during earthquake site investigations here, and elsewhere, in Türkiye [1,44,45]. The damage and failure of many RC buildings can be explained using these basic problems, among others.…”

Periodic structure as seismic barriers

“…Earthquakes cause huge property damage and deprive many people of their lives, and approximately two earthquakes occur per minute on the earth [1]. The conventional seismic isolation methods include passive control, active control, and hybrid control techniques [2][3][4][5][6], and generally, these techniques often have little effect on large earthquakes [7]. A periodic structure made of phononic crystals and locally resonant metamaterials acts as seismic wave barriers to greatly attenuate the amplitude of seismic waves before they reach the protected target [8][9][10][11][12].…”