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This study investigates the seismic residual performance of reinforced concrete (RC) shear walls with different levels of earthquake damage through reversed cyclic loading tests. The test specimens include slightly damaged walls, moderately damaged walls, and repaired specimens after moderately damaged walls. From the test and analysis results, it is evident that the residual strength and deformation capacity of slightly and moderately damaged RC shear walls do not decrease compared with the undamaged wall. However, the residual stiffness and energy dissipation capacity of damaged walls significantly decrease. The test results are also compared with the reduction factors for residual stiffness, strength, deformation capacity, and energy dissipation capacity in the FEMA 306 and JBDPA post-earthquake assessment guidelines to assess their applicability. Additionally, this study proposes a simplified model to describe residual lateral capacity curves of damaged RC walls at different damage levels for nonlinear pushover analysis, allowing engineers to easily convert the capacity curves of undamaged walls to damaged ones.

This paper contains technical information related to the Dinar project for the rehabilitation of moderately damaged reinforced concrete buildings after the 1 October 1995 Dinar earthquake. The structural appraisal of the damaged buildings, analytical studies leading to decisions regarding structural rehabilitation or demolition, the supervision on site of the rehabilitation and the overall coordination of the project was entrusted to the Middle East Technical University Earthquake Engineering Research Center [METU-EERC] by the Turkish Ministry of Public Works and Settlement. The project involved the rehabilitation of 35 moderately damaged RC buildings with a total floor plan area of 22 000 square metres.

An earthquake of magnitude 6.2 (M_b) occurred in west-central part of Colombia on January 25, 1999. This earthquake is officially called Quindio Earthquake from the name of the most affected province. The earthquake caused disastrous damage to a large number of buildings resulting in significant casualties. In Armenia City and its neighbouring villages close to the epicentre over 1000 people were killed by the earthquake and the total monetary loss reached US$ 2 billion. Armenia City, which has an approximate population of 280 000 people, apparently suffered the worst in terms of casualties and damage to the buildings.

The present paper focuses on the causes of damage to houses and buildings in Armenia City. First, the evolution of the urban area of the city was investigated using historical features available maps from each era. Then a correlation between buildings damage and topographical features of the city was studied. The effects of geological features and amplification of ground motion were also investigated.

In 1995, a swarm of earthquakes affected the city of Dinar, Turkey, which is located in Southwest Anatolia and has a population of 35 000. The mainshock having a local magnitude of 5.9 occurred on 1 October 1995. It was preceded by foreshocks in the previous four days, the largest one with a magnitude of 4.7. These foreshocks initiated structural damage in many buildings, which was then severely aggravated by the mainshock and a strong aftershock two hours later, with a magnitude of 5.0. Numerous aftershocks were recorded throughout the following three months. Strong ground motions were recorded within the city. The mainshock produced peak horizontal accelerations of 0.28 g and 0.29 g. The Dinar earthquake caused a death toll of 92 and more than 200 injuries. The economic losses due to structural damage alone are estimated at 250 million USD.

A strong earthquake with a moment magnitude of $M_w=5$.9 according to the Disaster and Emergency Management Authority (AFAD) occurred at 04:08 local time on November 23, 2022, in Gölyaka district of Düzce province that is located in the Western Black Sea region of Turkey. The earthquake with a shallow focus is 0.82 km away from Kemeryani village of Gölyaka district, which is the nearest settlement. According to observation data, the highest acceleration value of the earthquake was measured as 407.76 gal (0.410 g) in the East-West component measured from the 8102 coded Düzce Central accelerometer station, which is one of the five accelerometer stations closest to the earthquake zone. There was no loss of life in the earthquake, in which 93 people were injured. However, damages occurred due to the earthquake in structures that were built before the year 2000 and did not receive good engineering and supervision services. It has been determined that the structures built after the year 2000 received good engineering and supervision services performed better. The purpose of this study is to ensure that the experience gained as a result of the investigations about the earthquake that occurred will be made permanent and usable. For this purpose, damage and collapses that occurred on the buildings due to earthquake are examined based on field investigation. The types and causes of damage that occurred on both reinforced concrete and masonry buildings are evaluated in detail with considering the conditions of the existing Turkey Building Earthquake Design Code. The seismological characteristics of the earthquake are also evaluated. In addition, the earthquake hazard of Düzce Province is evaluated together with the earthquakes experienced in the past years, which caused significant loss of life and property in the region.

Two catastrophic earthquakes occurred in the Eastern Anatolian Fault Zone on February 6, 2023, in the city Kahramanmaraş in Türkiye and directly affected the Eastern and South-Eastern Anatolia regions, where 15 million people live. These earthquakes are among the most destructive earthquakes in the history of Türkiye and destroyed both old and new structures. While many studies have been conducted to report the caused damage in the existing building stock, common damage is worth in-depth discussion since it was observed in the seismic code-compliant new buildings. This damage is the buckling of compression reinforcement (BCR) in reinforced concrete beams. In this study, the observed damage mechanism has been evaluated with the design requirement of the recent seismic codes of Türkiye. The principles of anti-buckling design requirements in literature were searched and a certain deficiency in the codes was revealed. The outcomes of the study have been applied to an existing newly constructed reinforced concrete building that experienced BCR damage in its beam. It has been demonstrated that beams designed according to Türkiye’s recent seismic codes may fail to reach the ductility level specified in the literature due to buckling of their compression bars under extreme loading.

Pounding of adjacent buildings or parts of buildings due to earthquake shaking is often implicated as a significant source of damage. The majority of theoretical studies of pounding have focused on determination of the minimum separation required to prevent pounding. While this is useful for design of new structures, a great many existing structures are not sufficiently separated to preclude pounding. For these existing structures it is clearly useful to have a measure of the expected level of damage that may occur in future earthquakes. This paper attempts to assess the effects of pounding from measured earthquake records. The concept of Maximum Impact Velocity Spectrum (MIV) is introduced. The MIV records the envelope of the maximum impact velocity obtained during the earthquake for all separation distances as a function of the structure's natural period. Several measured earthquake records are considered and some surprising results are obtained.