Assessment and mitigation of earthquake-induced landslides in Philippine infrastructure

A case study of an industrial facility located in Central Philippines is presented. A magnitude 6.5 earthquake hit Leyte province on 6 July 2017. The tremor was an extreme event such that even slopes with moderate landslide susceptibility ratings failed. Major facilities, such as power plants, pipelines, and access roads were heavily damaged. Hazard assessment was conducted in several facilities to determine post-earthquake conditions of the surrounding terrain (slopes, waterways, etc.) and of the structures. Among the areas inspected, nine (9) areas within the facility were tagged as "high" risk areas. Thus, detailed engineering was done to mitigate the recurrence of hazards. Structural measures such as soil nailed wall system, mechanically stabilized earth (MSE) walls, and micropiles as cut-off wall were proposed as landslide mitigating measures. Moreover, non-structural measures were also proposed in order to minimize the risk of further landslide.