Physical vulnerability assessment of damaged buildings to the Shenzhen catastrophic CSW landslide

An increasing number of dumpsites have been built to stockpile a large amount of construction solid waste (CSW) during urbanization. Physical vulnerability assessment to CSW landslides plays a critical role in evaluating the safety risk of the potentially affected buildings. A catastrophic CSW landslide occurred in Shenzhen, China, in December 2015, which directly destroyed 75 buildings along the travel path. In this study, based on the statistical fundamental information of the damaged buildings and the reproduced motion process of the landslide using numerical modeling, both simulation-based progressive destruction process characterization and statistical-based analyses of the relationships between intensity data and vulnerability indexes are comprehensively performed to quantify the physical vulnerability of the damaged buildings, identify the failure models, and determine critical factors for controlling the building damages subjected to the Shenzhen CSW landslide. A typical vertical continuous collapse model due to the bending failure of the bottom column and the upward extension of the plastic hinge area is observed in the established single-frame structure under a set of impact pressure data. The occurrence of building failures close to the time of peak impact pressures controlled by the dynamic pressure indicated by velocity, along with the recorded flow velocity and impact pressure data exceeding the corresponding threshold values for all affected buildings, both suggest that flow velocity and impact pressure indicators are more appropriate for quantifying the vulnerability of buildings exposed to high-mobility CSW landslides. The conclusions could help CSW dumpsite stakeholders to better perform risk assessment and mitigate hazard propagation.