Influence of Fines Content on the Stability of Volcanic Embankments under Rainfall and Earthquake

Abstract

This study aims to investigate the effects of fine content on the mechanical behavior of embankments constructed from volcanic soil subjected to rainfall and earthquake. To accomplish this purpose, a series of 1 g model experiments on slopes using Komaoka volcanic coarse-grained soils as materials was conducted with a spray nozzle and shaking table. In the experiments, shear strain, acceleration, pore water pressure, and saturation degree were monitored and measured to provide an understanding of the failure mechanism of the model embankment with different fine particle contents during post-rainfall earthquakes. The results show that the increase in the fines content of the volcanic soil reduces the permeability of the volcanic embankment but has no significant effect on rainfall-induced slope failure until the shear strain is less than 6%. Moreover, the seismic resistance of volcanic slopes subjected to previous rainfall increases when the fine particle content increases to a certain threshold of about 27%.

Rainfall-Induced Geological Disasters

“…Based on the different types of geological hazards studied, the 14 papers of this Special Issue can be classified into three parts: landslide or slope [1][2][3][4][5][6][7][8][9][10][11], debris flow [12,13] and other geological disasters [14]. Studies on landslides or slope mainly focus on triggering factors [1][2][3], deformation and failure process [4][5][6], slope stability [7,8], risk assessment [9] and prevention measures [10,11].…”

“…A case study of the Wenchuan earthquake-affected area was conducted by Yang et al [13] to investigate the characteristics of debris flow activities at different scales after the disturbance of strong earthquakes. In addition, using a series of 1 g model experiments, Nguyen et al [14] explored the effects of fines content on the mechanical behavior of embankments constructed from volcanic soil subjected to rainfall and earthquakes.…”