REDUCING EARTHQUAKE VULNERABILITY OF NON-ENGINEERED BUILDINGS: CASE STUDY OF RETROFITTING OF SCHOOL BUILDING IN INDONESIA

摘要

Recent earthquakes in Indonesia caused major damage to buildings and infrastructures. Most of the damage occurred on non-engineered buildings, which were built traditionally with very little or no assistance from qualified engineers. About two thirds of the buildings in Indonesia are non-engineered, most of them are one-story and two-story structures. Studies show that problems for these buildings were caused by minimum reference to standards/codes, lack of detailing, wide variety of quality of materials and construction methods,and improper structural design. Therefore, non-engineered buildings tend to have low structural quality and to be susceptible to earthquake. However, experience also revealed that non-engineered buildings can survive earthquakes with little or no damage, provided that they were built properly using good quality of materials and good workmanship. Considering large number of non-engineered buildings, efforts should be made to make these buildings safer. Several applicable solutions include developing systems for dissemination of building standards/codes, producing field manuals/guidelines, developing seismic risk map for Indonesia, and developing appropriate building technology to reduce structural damage. These solutions should be accompanied by the evaluation of existing structures to improve their safety against future earthquake risk. If these buildings were found to be vulnerable to earthquake, retrofit strategies should be designed and conducted. A case study of retrofitting of a school building in Bandung was given as an example of efforts in reducing vulnerability for non engineered buildings. The retrofitting work was complemented with several activities to reduce the earthquake vulnerability of the school community.