A Case Study on the Soil Liquefaction Monitoring at a High Potential of Soil Liquefaction Area in Taiwan

The Meinong earthquake that impacted southern Taiwan in 2016 resulted in over a thousand buildings in Tainan being damaged due to soil liquefaction. To aid future building foundation design considerations and reduce the possibility of building damage, the Taiwan government has established a medium precision 3D soil liquefaction susceptibility map by conducting extensive site investigations and laboratory tests. Preliminary assessments and past experience indicate a high liquefaction potential area near Dawan Elementary School in Tainan City. To verify the accuracy of the soil liquefaction susceptibility map and provide subsoil monitoring data for updates, this study establishes a soil liquefaction monitoring station at Dawan Elementary School. A steel mini suction bucket, installed using jacking and suction penetration methods, was employed as the monitoring platform. On April 3, 2024, a magnitude 7.3 earthquake occurred in Hualien, Taiwan, with an acceleration of about 30 gal recorded at the Tainan seismic station. The soil liquefaction monitoring station successfully detected an accumulation of excess pore water pressure responses, demonstrating that the system can reliably provide monitoring data for liquefiable soil layers, which serves as a reference for updating the 3D soil liquefaction susceptibility map.

Keywords: Soil liquefaction, Mini suction bucket, Monitoring system.