Experimental study on the benefits of nature-based solutions for debris-flow mitigation via synergistic eco-geotechnical measures

Research on nature-based solutions (NbSs) for mitigating debris-flow hazards has increased interest in eco-geotechnical systems. Most studies focused on the efficiency of isolated mitigation measures, while the benefits and mechanisms of coordinated approaches remain unclear. Consequently, this study proposed a novel approach to mitigating debris-flow velocity, sediment transport, and energy by utilizing tree-shrub mixed-vegetation filter strips (T-SMVFS) along S-shaped flow paths combined with dams. The optimal design determination involved four steps: 1) optimal T-SMVFS row and stem spacings were determined; 2) S-shaped flow path parameters were set based on width ratios; 3) effects of synergistic and individual measures on debris-flow reduction were compared; and 4) a flow velocity reduction equation was constructed, considering the influence of topographic features, vegetation planting patterns, and debris flow properties. Results revealed that a completely covered T-SMVFS with row ..., Simulated flume experiments were performed with different stem and row spacings with mixed shrub-tree vegetation to investigate the effects of coupling ecological and geotechnical measures on debris-flow sediment interception, flow discharge, velocity, and grain size. The experiment primarily consisted of three parts: In Part 1, this study explores the interception effect of full-cover vegetation arrangement on debris flow movement and obtains the optimal row and stem spacing. Part 2, it examines the influence mechanism of S-shaped flow path width variation on debris flow movement under optimal row and stem spacing. Part 3, it analyzes the mechanism and benefits of the integrated S-shape vegetation filter strip and geotechnical measures. To monitor sediment deposition, a grid was positioned on the glass retaining wall of the flume along the direction of water flow to track the sediment's height and morphology. Three laser mud level meters (Leuze, ODSL 30/V-30M-S12, 10 Hz) and two c..., , # Data from: Experimental study on the benefits of nature-based solutions for debris-flow mitigation via synergistic eco-geotechnical measures

[https://doi.org/10.5061/dryad.j0zpc86r7](https://doi.org/10.5061/dryad.j0zpc86r7)

## Description of the data and file structure

Through the flume experiment, the following data were collected: (1) Bulk density. Weight (*m*) and volume (*V*) were measured and used to calculate bulk density *ρ* using the formula *ρ* = *m*/*V*.

(2) Flow depth. The flow depth (*h*) was measured using lasers #I, #II, and #III.

(3) Velocity. Two cameras, labeled Camera #1 and #2, were placed above the baffles to capture the surface velocity of the debris flow. The recordings were captured before (Camera #1) and after (Camera #2) the shrub filter strip. A reference material, a table tennis ball, was used to measure the distance (*s,* unit: centimeter) traveled within a specific time (*t*, unit: second). Subsequently, the velocity of debris flow movement (*v*) was ...,