Rainfall-Induced Geological Disasters

The Special Issue “Rainfall-Induced Geological Disasters” focuses on the recent advances in disaster mechanisms, risk assessments and prevention measures for rainfall-induced geological disasters. Rainfall is a primary cause of geological disasters such as landslides and debris flows. Understanding the mechanism of these disasters and designing effective control and mitigation measures is of great importance for people, infrastructure, lifelines and economic activities. This Special Issue comprises 14 papers from China, Taiwan, Japan and other country and regions. All papers present new findings and meaningful insights through experiments, model tests, theoretical methods, or numerical simulation. We consider that the main goal has been successfully reached, and we hope the readers of the journal can gain some new knowledge or inspiration about rainfall-induced geological disasters from the published papers.

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]. The rainfall threshold for shallow landslides was analyzed by use of the physically based model for rainfall-induced landslides in Rasuwa District, Nepal [1]. Authors of [2] conducted a statistical analysis of the potential of landslides triggered by the combination between rainfall and earthquakes. The coupled effect of slope runoff and seepage on slope instability was numerically studied in [3]. The deformation and failure process of the rainfall-induced landslide was studied by Pan et al. [4] through large-scale physical model tests for the Zhaoshuling Landslide in the Three Gorges Reservoir Region; by Gu et al. [5] through field investigations and monitoring for the Fangshan landslide in Nanjing, China; and by Wei et al. [6] through a numerical simulation for the Shaziba Landslide in Enshi, China, respectively. Rainfall infiltration can change the infiltration line and seepage field of the slope body [7]; it can cause suction loss of the slope matrix [8], thereby affecting the stability of unsaturated soil slopes. Sun et al. [7] and Yang et al. [8] studied this issue using model tests and strength reduction FEM, respectively. A quantitative risk assessment is important for disaster prevention and reduction. Sui et al. [9] explored the risk assessment method for rainfall landslides, and some preventive measures and their effect were studied by Cheng et al. [10] and Wang et al. [11].

Besides landslides, debris flow is another major rainfall-induced geological disaster. Zhang et al. [12] presented the runout simulation and risk assessment of the Boshuigou debris flow under different rainfall conditions in Wudu district, Gansu Province, Northwest China. 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.