Key points are not available for this paper at this time.
The recent discovery of the Central Davao Fault System leads to assessing the buildings' seismic performance close to the area. DOST-PAGASA released the Earthquake Atlas, "Metro Davao Earthquake Model," that shows research data and valuable information that would be used in designing new structures and seismic evaluation. Using this Earthquake Atlas, a Four Storey Professional School Building in the University of Mindanao was assessed using ASCE/SEI 41. Structural Engineers and Practitioners widely use the code for Seismic Evaluation of Existing Buildings. As-built plans were acquired first for data collection and structural modelling, analyze using SAP 2000 software and perform a seismic evaluation using the results of the analysis in accordance with ASCE 41 standard; and for the output, provide an evaluation report of the structure’s performance. Using first (ATC 40), second (FEMA 356), and next-generation (FEMA 440 and ASCE 41-13) seismic design principles, the structure was evaluated according to the selection of performance objectives and seismic level. Linear and Nonlinear analyses were employed. Pushover curve was drawn from SAP 2000 for two actions of plastic hinge behavior, deformation-controlled and force-controlled actions. The target performance objective of the structure in this study is Life Safety Level at 10 % probability of exceedance in 50 years with 5% damped based on ASCE 41-13 standard. The assessment results show that the structure did not meet the criteria for life safety level requirements in ASCE/SEI 41 for columns, particularly on the first and last floor level for linear analysis procedure. A few numbers of beams also did not meet the standards, specifically on the roof beam level. The displaced ductility ratio was found to be 3.47 (moderately ductility demand). In nonlinear analysis, the structure also failed to meet the base shear requirements for both deformation and forced controlled actions in Pushover analysis. Performance base shear Vp of 3.233 exceeded the acceptable limit of less than 1.0. The first modal period 1.976 seconds was also notably higher than the building period of 0.647 seconds which indicates structure's low stiffness. These findings were evidence that the structure should undergo retrofitting procedures to meet seismic performance objectives and strengthen the structure's resilience to earthquake damages.
Cabotaje et al. (Mon,) studied this question.