การเพิ่มความสามารถต้านทานแผ่นดินไหวของอาคารเรียนคอนกรีตเสริมเหล็ก

• Main Author: ธานินทร์ เจียรักสุวรรณ
• Other Authors: ทศพล ปิ่นแก้ว
• Format: Theses and Dissertations
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 2001
• Subjects: อาคารคอนกรีตเสริมเหล็ก; แผ่นดินไหว; การออกแบบต้านทานแผ่นดินไหว; Buildings, Reinforced concrete; Earthquakes; Earthquake resistant design
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:46638
• Institution: Chulalongkorn University

Since 1997, the Ministerial Regulation No. 49 has been enforced on the new buildings in the northern and western part of Thailand for seismic resistant design. However, almost all of existing buildings were constructed before 1997. Their seismic resistances are in questions. Therefore, it is worth to investigate their behavior and performance under earthquakes, especially for the public buildings. This research studies the seismic resistance and seismic retrofit of 4-story and 2-story reinforced concrete school buildings. The buildings were designed to resist only gravity load. Both inelastic pushover and inelastic dynamic analysis under the earthquake records are conducted using the computer program IDARC with 2D building models. The obtained results show that these buildings exhibit weak column-strong beam behavior under the earthquakes. For the earthquakes with PGA of 0.10g, the 4-story building suffers minor damage, while the 2-story building suffers moderate to severe damage. A number of plastic hinges are developed in columns but are limited for some simply supported beams. For the earthquakes with PGA of 0.20g, these buildings suffer severe to collapse damage. The damage is found to be concentrated in the 1sl story columns. Consequently, the buildings trend to collapse due to mechanism of this floor. Under the earthquake with PGA of 0.15g that recommended for Thailand s seismicity, the 4-story building suffers severe damage. Three retrofitting techniques consisting of a column jacketing, a full-filling reinforced concrete shearwall inside the existing frame and an installation of viscous elastic damper are employed. Each technique is found to be able to reduce the building damage to minor and moderate damages for the earthquakes with PGA of 0.10g and 0.20g PGA, respectively. Strengthening by full-filling shearwall inside the existing frame is the most preferable solution for the 4-story building because the damage is lowest with uniformly spreaded and there are too many columns need to be strengthened if the column jacketing technique is adopted. Although this technique seems preferable for the 2-story building.