In northeast Pakistan, the Azad Jammu and Kashmir region is seismically active. A 7.8 MW-magnitude earthquake devastated the area in October 2005. Another earthquake struck the same region in September 2019. Following this event, field surveys were conducted to record the damage. While most of the structures in this region were low rise, some were medium rise. Researchers Muhammad Masood Rafi, Muhammad Ahmed, Sarosh Hashmat Lodi, Humberto Varum, and Muhammad Tausif Arshad analyzed the damage to study seismological aspects of the earthquake and seismic performance of damaged RC buildings.
Their paper, “Investigation of Damage to Reinforced Concrete Buildings Due to the 2019 Mirpur Earthquake, Azad Kashmir” in the Journal of Performance of Constructed Facilities presents observations about the performance of reinforced concrete buildings as a result of the 2019 earthquake. Their analysis also included ground acceleration recordings. Learn more about the conclusions drawn from their study in https://doi.org/10.1061/(ASCE)CF.1943-5509.0001749. The abstract is below.
Abstract
This paper presents the results of damage surveys in Mirpur, in the Azad Jammu and Kashmir region of Pakistan, which was affected by a moderate earthquake on September 24, 2019. The epicenter of this earthquake was near the city of Mirpur at a shallow depth of no more than 10 km. Rupture of ground surface was observed in the area close to the epicenter, which can be associated with the release of seismic energy at shallow depths. The ground acceleration recorded at the site close to the epicenter was influenced by the rupture directivity effects. A significantly high vertical component of ground acceleration was observed at a site in close vicinity of the epicenter. Ground-motion amplification was also indicated by the data analysis in the presence of soft soil. A few low- to medium-rise reinforced concrete buildings were severely damaged by the ground shaking. The columns in these buildings experienced compression or shear-compression mode of failure in the presence of high axial compression applied by the vertical seismic forces and/or overturning moment. The longitudinal bars in the columns also buckled due to high axial compression demands coupled with insufficient confinement in the plastic hinging regions.
Read the paper in full in the ASCE Library: https://doi.org/10.1061/(ASCE)CF.1943-5509.0001749.
