Assessing the vulnerability of Kota Kinabalu buildings

A gradual increase in moderate and low seismic activity has occurred in Sabah over the course of several years due to the presence of certain moderately active fault lines in the region. Around 300 moderate earthquakes with magnitudes ranging from MW 4.0 to 7.0 have occurred in the last 120 years. The majority of existing buildings in Sabah are wind and gravity loaded. This study proposes a preliminary seismic vulnerability assessment methodology based on empirical and analytical vulnerability method for 250 existing buildings in Kota Kinabalu city. The empirical vulnerability assessment focuses on building evaluation utilizing a standard Rapid Visual Screening (RVS) method and the FEMA 154 guidebook's moderate seismicity assessment form. A field survey was conducted on the buildings ranging in height from low-rise to high-rise. As a result, when subjected to moderate-intensity earthquakes, 60% of the buildings are classed as susceptible and vulnerable to seismic hazard. The current study included the use of nonlinear static analysis to seven different building cases for further investigation. The findings of the analysis demonstrate that the majority of the buildings respond linearly elastical when subjected to peak ground acceleration (PGA) at 0.17g, which indicate that, buildings without seismic design accumulate damage early when subjected to moderate earthquake loadings

Seismic vulnerability assesment of selected buildings in Kota Kinabalu, Sabah

June 5th 2015 incident in Ranau, Sabah has brought the attention of both local and international researchers due to the 6.0 magnitude of earthquake that hit the district. It was the most powerful earthquake ever recorded in Borneo for the past 120 years since 1900. The records of loses demonstrate the significant needs for seismic vulnerability assessment on the existing buildings in the effected state. The objective of this study is to investigate the building vulnerabilities in the capital city of Sabah, Kota Kinabalu. Then, to establish a performance level of the existing buildings. Case buildings include major government buildings and facilities, educational and institutional buildings, residential buildings, commercial as well as public buildings. The empirical vulnerability assessment involves 250 number of buildings evaluations by Rapid Visual Screening according to FEMA 154 (2002). Local ground motion data indicates that Sabah is a region with moderate seismicity level. Case buildings ranging from low-rise to high-rise were screened with Level 1 assessment form and categorized into two groups; hazardous and non-hazardous, based on the determined final value “cut-off value”. 60.4% of the case buildings deem to be potentially seismically hazardous under local ground excitation. 38.54% of the building stock possesses limiting seismic performance criteria and put forward for further seismic vulnerability assessment. Second part of this study involves analytical vulnerability assessment by means of Nonlinear Static Analysis (Pushover Analysis) using Capacity Spectrum Method. 7 case buildings were modeled into engineering software and evaluated with the highest expected ground excitation magnitude at 0.17ag with 10% probability of exceedance (PE) and 50 years design time period with respect to 2,475 return periods. Considering elastic damping at β° = 5% , all case buildings are assumed to be Type B category. Analysis of building performance results show majority of the building stock give a linearly elastic response under the local seismic excitation. Structures without seismic code compliance were estimated to show early damage accumulation due to ground shaking

Assessing the vulnerability of Kota Kinabalu buildings

A gradual increase in moderate and low seismic activity has occurred in Sabah over the course of several years due to the presence of certain moderately active fault lines in the region. Around 300 moderate earthquakes with magnitudes ranging from MW 4.0 to 7.0 have occurred in the last 120 years. The majority of existing buildings in Sabah are wind and gravity loaded. This study proposes a preliminary seismic vulnerability assessment methodology based on empirical and analytical vulnerability method for 250 existing buildings in Kota Kinabalu city. The empirical vulnerability assessment focuses on building evaluation utilizing a standard Rapid Visual Screening (RVS) method and the FEMA 154 guidebook’s moderate seismicity assessment form. A field survey was conducted on the buildings ranging in height from low-rise to high-rise. As a result, when subjected to moderate-intensity earthquakes, 60% of the buildings are classed as susceptible and vulnerable to seismic hazard. The current study included the use of nonlinear static analysis to seven different building cases for further investigation. The findings of the analysis demonstrate that the majority of the buildings respond linearly elastical when subjected to peak ground acceleration (PGA) at 0.17g, which indicate that, buildings without seismic design accumulate damage early when subjected to moderate earthquake loadings