Bedrock topography is known to affect subsurface water flow and thus the spatial distribution of pore water pressure, which is a key factor for determining slope stability. Therefore, the aim of this study is to investigate the effect of bedrock topography on the timing and location of landslide initiation using 2D and 3D simulations with a hydromechanical model and the Local Factor of Safety (LFS) method. A set of synthetic modeling experiments was performed where water flow and slope stability were simulated for 2D and 3D slopes with layers of variable thickness and hydraulic parameters. In particular, the spatial and temporal development of water content, pore water pressure, and the resulting LFS were analyzed. The results showed that the consideration of variable bedrock topography can have a significant effect on slope stability and that this effect is highly dependent on the intensity of the event rainfall. In addition, it was found that the consideration of 3D water flow may either increase or decrease the predicted stability depending on how bedrock topography affected the redistribution of infiltrated water. pore water pressure [1,2,21] and reduce matric suction [23]. Accordingly, the suction stress and the effective stress, which is the sum of the total stress and the suction stress [24] are reduced. Such a reduction in the effective stress reduces the shear strength of the soil, which may cause failure in the hillslope [12,25]. Therefore, a dynamic assessment of coupled hydromechanical processes in variably saturated hillslope is valuable to assess slope stability.A wide range of studies has focused on developing models to predict the timing and distribution of rainfall-induced landslides [26][27][28]. Many studies have used simplified representations of water flow and determined slope stability using simple limit-equilibrium methods (e.g., infinite-slope stability method) despite well-known limitations [29] such as the required a priori knowledge of the shape of the failure plane and the overestimation of slope stability [30]. Most studies have also focused on 2D slope stability modeling even though some studies have shown that 2D and 3D slope stability assessments can differ considerably [31]. Recently, the local factor of the safety (LFS) concept was proposed to assess slope stability [30]. This Coulomb stress-field based method describes the stability status of cohesive variably saturated soils at each point within hillslopes and does not require a priori assumptions with respect to the location and shape of the failure plane. By taking full advantage of modern numerical solutions for variably saturated flow and stress distribution in hillslopes, the LFS method can be applied on unstructured meshes with high accuracy. Lu et al. [30] showed that the results of stability assessment using the LFS method are in agreement with results of conventional methods while, at the same time, providing further insights into the initiation and evolution of the potential failure surface. Therefore, the LFS method ...

This study investigated the effects of nano‐silicon dioxide (nano‐SiO2) (0%, 0.5%, 1%, and 1.5%) and the ratio of PVA/gelatin (1:1 and 2:1) on the physicochemical and structural properties of gelatin/polyvinyl alcohol composite films. The results showed that the highest value of tensile strength (18.05 MPa) was found for a PVA/gelatin ratio of 2:1 and 1% nano‐SiO2 (P2:G1‐1%). The films’ elongation at break value increased with increases in the nano‐SiO2 and PVA content, while their water solubility decreased with the addition of nano‐SiO2. Their water vapor permeability decreased with 1% nano‐SiO2, and the lowest value for water vapor permeability was with P2:G1‐1%. Fourier transform infrared and differential scanning calorimetry results showed that appropriate interaction between both polymers and nano‐SiO2 was found with P2:G1‐1%. Scanning electron microscopy illustrated a compact structure and good compatibility of nano‐SiO2 with gelatin in P1:G1‐1% film. X‐ray diffraction results showed that the crystallization peak intensity of P2:G1‐1% was higher than that of P1:G1‐1% nanocomposite films. Overall, the results indicated that the concentration of 1% of nano‐SiO2 in P2:G1 films significantly improved the films’ physicochemical and structural properties. These results suggest that they could be useful as food‐packaging materials to maintain food quality. Practical application Gelatin films possess properties that make them useful in packaging, such as water vapor resistance and low values for mechanical properties. PVA as a synthetic polymer, have good tensile strength asz and biodegradability along with high numbers of hydrophilic groups. PVA has also been used in many biomaterial applications. Some advantages of nanomaterials such as silica nanoparticle are high mechanical strength, biocompatibility, and biodegradability. In the present study, nano‐SiO2 was used in films blended from PVA and gelatin. The improved physicochemical and structural properties achieved through the use of nano‐SiO2 could make the films more effective as food packaging.

Rainfall-induced landslides are a disastrous natural hazard causing loss of life and significant damage to infrastructure, farmland and housing. Hydromechanical models are one way to assess the slope stability and to predict critical combinations of groundwater levels, soil water content and precipitation. However, hydromechanical models for slope stability evaluation require knowledge about mechanical and hydraulic parameters of the soils, lithostratigraphy and morphology. In this work, we present a multi-method approach of site characterization and investigation in combination with a hydromechanical model for a landslide-prone hillslope near Bonn, Germany. The field investigation was used to construct a three-dimensional slope model with major geological units derived from drilling and refraction seismic surveys. Mechanical and hydraulic soil parameters were obtained from previously published values for the study site based on laboratory analysis. Water dynamics were monitored through geoelectrical monitoring, a soil water content sensor network and groundwater stations. Historical data were used for calibration and validation of the hydromechanical model. The well-constrained model was then used to calculate potentially hazardous precipitation events to derive critical thresholds for monitored variables, such as soil water content and precipitation. This work introduces a potential workflow to improve numerical slope stability analysis through multiple data sources from field investigations and outlines the usage of such a system with respect to a site-specific early-warning system.

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