Hydro-Mechanical Interactions in Fractured Rock Masses

Hydro-mechanical interactions in fractured rock masses encompass the coupled processes by which fluid flow alters the mechanical behaviour of discontinuities and, conversely, mechanical deformation influences fluid pathways. Fractures and faults serve as preferential conduits for water, governing permeability, pore pressure distribution and stress redistribution at multiple scales. In partially saturated regimes, capillary forces and variable aperture sizes induce non-Darcean flow, while in fully saturated zones, pressure transients can trigger slip or dilation along fracture surfaces. Thermo-hydro-mechanical (THM) coupling further complicates this behaviour: changes in temperature modify rock stiffness and fluid viscosity, and reservoir impoundment can induce cooling or heating fronts that drive stress changes. Numerical approaches—ranging from continuum finite-element schemes with embedded discontinuities to discrete fracture network models—have elucidated how fracture geometry, roughness and connectivity control seepage evolution, deformation patterns and potential instability. The global significance of this field spans dam safety, geothermal energy extraction, waste disposal and groundwater management, where predictive capacity for long-term fluid-structure feedback is essential. Recent advances have sharpened understanding of infiltration dynamics, partitioning of flow at fracture intersections and the evolution of permeability under sustained hydraulic loading, highlighting both the challenges and opportunities in linking laboratory insights to field-scale applications.

Research from Nature Portfolio

Recent studies have advanced the understanding of reservoir-induced deformation through coupled THM analysis in fractured limestone aquifers. Detailed field observations downstream of a major arch dam revealed significant canyon contraction and uplift movements associated with reservoir impoundment. Finite-element THM simulations reproduced the observed deformation by accounting for temperature drops in the bedrock and increased pore pressures within underlying aquifers. The model demonstrated that cooling of the limestone layer leads to contraction, while elevated fluid pressures promote dilation, together driving large-scale canyon movements. This integrated approach has provided refined safety assessments for dam structures under varying impoundment scenarios and clarified the dominant processes behind unprecedented deformation phenomena.

Hydro-Mechanical Interactions in Fractured Rock Masses publication trend

The graph below shows the total number of articles in hydro-mechanical interactions in fractured rock masses across all publications each year (not limited to Nature Index journals).

Technical terms

Fracture network: An interconnected system of cracks and joints through which fluid preferentially flows.

Hydro-mechanical coupling: Mutual feedback between fluid pressures and mechanical stresses in a porous or fractured medium.

Thermo-hydro-mechanical (THM) coupling: Integrated process in which temperature changes, fluid flow and mechanical deformation interact.

Preferential pathways: High-conductivity channels within a rock mass that dominate fluid transport.

Dual-domain model: A representation separating flow and storage in fractures (mobile domain) and the surrounding rock matrix (immobile domain).

References

1. Mechanism for large-scale canyon deformations due to filling of large reservoir of hydropower project. Scientific Reports (2020).
2. Laboratory experiments and dual‐domain modeling of infiltration dynamics in partially saturated fractured porous media. Vadose Zone Journal (2022).
3. Numerical and Analytical Modeling of Flow Partitioning in Partially Saturated Fracture Networks. Water Resources Research (2021).
4. Seepage Evolution Model of the Fractured Rock Mass under High Seepage Pressure in Dam Foundation. Advances in Civil Engineering (2021).