🏔️ Himalayan Surge Hydrodynamics Simulator China-Nepal Corridor Model

● TERRACE INTACT (STABLE)

SURGE TIME: T +0.0s

GORGE PRESETS

Catchment Slope 24°

Peak Discharge (Q) 2,650 m³/s

Sediment Volume Fraction 32% (Hyperconcentrated)

Structural Framing

REAL-TIME HYDRO-TELEMETRY

Surge Velocity (V)

0.0 m/s

Dynamic Impact (P)

0.0 kPa

Footing Scour Depth

0.0 m

Overturning Factor

0.00 FOS

Hydraulic Mechanism of the China-Nepal Gorge Collapse

"When flash floods hit the China-Nepal border late last month, surveillance footage captured the dramatic moment a five-story building was engulfed by a wall of water. CNN’s Simone McCarthy was among the first group of foreign media to visit the site..."

In steep Himalayan gorges (gorge bed slopes > 15°), torrential monsoon cloudbursts and glacial moraine failures create hyperconcentrated flood waves characterized by Froude numbers Fr > 1.2. The catastrophic failure of riverbank terraces results from a coupled hydrodynamic phenomenon: (1) Hydrodynamic Surcharge: sediment densities reaching 1,750 kg/m³ elevate dynamic frontal stagnation pressures past 150 kPa against first-floor columns. (2) Bed-Load Liquefaction & Toe Undercutting: intense basal shear stress (τ > 280 N/m²) strips non-cohesive alluvial terraces beneath foundation footings, eliminating passive lateral ground resistance and causing sudden structural toppling.