Hazard assessment of potential debris flow: A case study of Shaling Gully, Lingshou County, Hebei Province, China

Abstract

The debris flows in the Taihang Mountain region in North China are basically triggered by rainstorms. Firstly, the debris flow susceptibility of the Shaling Gully, Lingshou County, Hebei Province, China was analyzed in this paper to evaluate its hazard and effect on the downstream proposed structures. Secondly, the maximum flow depth and velocity of the potential debris flow in Shaling Gully were numerically simulated based on the FLO-2D model, and the simulation results indicate that the flow depths under the 50-year and 100-year rainstorms will have some effect on the downstream proposed structures. With debris flow intensity classification, the hazard of potential debris flow in Shaling Gully was classified. According to the flow depths and velocities simulated by FLO-2D model, the ARCGIS10.8 software was adopted to optimize the hazard zones, and therefore the hazard zonation map was established. With consideration of simulation results under natural conditions and other factors such as gully feature, a 4 m high and 40 m wide retaining dam was designed. The numerical simulation results show that the retaining dam may decrease the debris flow hazard to a negligible level, which offers some beneficial reference to the subsequent engineering design for Shaling Gully.

Quantification of red soil macropores affected by slope erosion and sediment using computed tomography

“…The soil cores were sampled at a collapsing gully at Huacheng Town (24°04′N, 115°38′E), north of Wuhua County, Guangdong Province, China (Figure 1b). Collapsing gullies are often close to residential and agricultural regions, and the often devastating soil erosion and mud sand flow events (Zhang & Liu, 2014) increase the risk for houses, roads, and farmlands (Figure 1c). Wuhua County is a representative subtropical monsoon region with a mean annual air temperature of 21.3°C, and a mean annual precipitation of 1507.2 mm (Zhang et al., 2020).…”

Hazard Assessment of Debris Flow: A Case Study of the Huiyazi Debris Flow

“…3 ⃝ various resistances can be simulated; 4 ⃝ the results include mud level, flow velocity, and intensity; and 5 ⃝ the results can be post-processed in GIS. The fundamental assumptions of simulating debris flow motion include the following: 1 ⃝ the motion process of the fluid is a shallow water wave motion mode; 2 ⃝ its motion equation satisfies the fixed-length flow equation; 3 ⃝ the distribution of fluid pressure is a hydrostatic pressure distribution; 4 ⃝ the elevation and Manning coefficient within each calculation grid are unique; and 5 ⃝ the flow pattern within the differential time interval is steady flow. The governing equations of the FLO-2D software are the constitutive fluid equations, including continuity equations and motion equations (dynamic wave momentum equations).…”

“…They often result in the destruction of buildings and other structures, posing serious threats to people's lives and property security. Due to their widespread distribution and significant hazards, research on debris flow disasters is of great importance for disaster prevention and mitigation [4][5][6].…”

Research on Spatial Distribution Pattern of Stability Inter-Controlled Factors of Fine-Grained Sediments in Debris Flow Gullies—A Case Study

“…Debris-flow-influencing factors and their relationships with the outflow, disaster chains, and principles of lateral erosion were studied, such as relationships between maximum runout amount and risk-assessment-influencing factors [19][20][21][22]. Based on these, models for danger sensing and prediction for debris flows were established, such as critical rainfall patterns [23], gully formation types [24], and hazard assessment and prevention models [25][26][27][28][29].…”