top of page
"Seismic Performance of Sub-standard Columns Subjected to High Axial Stresses and Long Term Loading."


Earthquakes are natural disasters that can cause significant damage to buildings, infrastructure, and human life. Unfortunately, many regions of the world that are prone to earthquakes have sub-standard building stocks, consisting of structures that are often constructed using low-strength concrete and poor reinforcement details. These sub-standard buildings are vulnerable to damage during earthquakes due to their limited deformation capacity and insufficient lateral stiffness and strength. These buildings fail to meet the requirements of modern seismic codes or even the design requirements of their time of construction. It is important to understand the challenges associated with sub-standard building stocks and work towards improving the seismic safety of buildings in earthquake-prone regions. In particular, the columns of these structures exhibit unsatisfactory and undesirable behavior under lateral loads, which can be attributed to low compressive strength of the concrete and inadequate reinforcement detailing. After the disastrous consequences of recent damaging earthquakes, the present state of seismic performance of the existing buildings has become alarming.


The scope of this study involved the production of full-scale RC column specimens, with a focus on investigating the seismic behavior of existing RC buildings' column inventory in the country. These columns are constructed using low-strength concrete and plain rebars with insufficient transverse reinforcement details. To simulate real-world conditions, the specimens were subjected to high axial load levels both before and during seismic tests. The main objective of the study was to investigate the effect of the ratio of axial load to the seismic behavior of the columns under lateral reversed cyclic loads. To achieve this, RC column specimens were axially loaded with constant axial load ratios ranging from 0.30 to 0.80, and exposed to seismic loads. In addition, other RC columns were continuously exposed to an axial load ratio of 0.70 for varying durations of 6, 12, 18, and 24 months, and monitored under sustained loading to determine axial deformations. This study is the first to investigate the combined effect of long-term axial load and lateral reversed cyclic loads on the seismic behavior of sub-standard RC columns.


Project Team

Alper İlki_edited.jpg

Prof. Dr.  Alper İlki


Principal Investigator


Assis. Prof. Dr.

Uğur Demir


WhatsApp Image 2023-03-10 at 18.02.26.jpeg

Assis. Prof. Dr.

Ö.Tuğrul Turan



Research Assis.

Safiye Gündoğan

PhD Student

bottom of page