Shear Behavior of Rock-Concrete Interfaces

The shear behaviour of rock-concrete interfaces underpins the stability of a wide range of civil and geotechnical structures, including tunnels, dams, retaining walls and foundations. At its core, interface resistance arises from a combination of frictional sliding, mechanical interlocking of surface irregularities and chemical or adhesive bonding. Surface morphology—from microscopic roughness to large-scale asperities—governs stress distribution and the mobilisation of shear strength under normal loading. Environmental factors such as temperature fluctuations and cyclic freeze–thaw action can alter pore structure, degrade adhesive bonds and promote microcracking, thereby reducing long-term interface performance. Experimental methods including direct shear tests, uniaxial compression trials and acoustic emission monitoring are complemented by numerical approaches such as distinct element modelling and finite element analysis. Together, these techniques reveal how material properties, interface geometry and external conditions interact to control shear resistance, energy dissipation and failure mechanisms. Improved understanding of these processes informs design guidelines for shotcrete linings, dam foundations and composite rock-concrete assemblies, with far-reaching implications for infrastructure resilience worldwide.

Research from Nature Portfolio

Recent studies have advanced knowledge of interface deterioration under environmental loading and coupled mechanical response. Laboratory investigations have characterised the evolution of pore structure and compressive strength in sandstone-concrete composites subjected to repeated freeze–thaw cycles. These experiments show that sandstone is more susceptible to pore enlargement and strength loss than concrete, that interface dip angle influences uniaxial compressive strength in a V-shaped pattern, and that porosity and strength follow a quadratic relationship under cyclic freezing. In parallel, combined uniaxial and triaxial compression tests, supported by numerical simulations, have demonstrated synergistic deformation in sandstone–concrete bodies. Peak stress and elastic modulus consistently lie between those of the individual materials, while interface geometry dictates local stress transitions from tension to compression. Energy analyses reveal storage before peak load and dissipation after failure, and damage variables correlate positively with confining pressure, illuminating plastic failure processes under multiaxial loading.

Shear Behavior of Rock-Concrete Interfaces publication trend

The graph below shows the total number of articles in shear behavior of rock-concrete interfaces across all publications each year (not limited to Nature Index journals).

Technical terms

Shear strength: The maximum tangential stress an interface can sustain before sliding failure occurs.

Asperity: A protrusion or irregular feature on a surface that contributes to mechanical interlocking.

Roughness: The texture of a surface, encompassing both micro-scale irregularities and macro-scale profile features that influence friction.

Freeze–thaw cycle: Repeated freezing and thawing of pore water within a material, leading to microstructural damage and strength degradation.

Uniaxial compressive strength (UCS): The maximum axial compressive stress a material can withstand under one-dimensional loading.

Cohesive frictional model: A constitutive framework that combines adhesive bonding and frictional resistance to describe interface shear behaviour.

References

1. Study on pore structure and the mechanical properties of sandstone-concrete binary under freeze–thaw environment. Scientific Reports (2023).
2. Experimental and numerical investigation of the mechanical properties and energy evolution of sandstone–concrete combined body. Scientific Reports (2024).
3. Influence of Concrete–Rock Bonds and Roughness on the Shear Behavior of Concrete–Rock Interfaces under Low Normal Loading, Experimental and Numerical Analysis. Applied Sciences (2022).
4. A 3DEC Numerical Analysis of the Interaction Between an Uneven Rock Surface and Shotcrete Lining. Rock Mechanics and Rock Engineering (2021).
5. Influence of large-scale asperities on the shear strength of concrete-rock interface of small buttress dams. Engineering Structures (2021).