Mechanical Behavior of Rock Under Chemical Corrosion

Rock formations subjected to chemical corrosion undergo a series of interrelated physico-chemical and mechanical changes that can profoundly affect their strength, deformability and permeability. Acidic or saline solutions induce mineral dissolution, salt crystallisation and ion exchange, leading to the gradual enlargement of microcracks and pores. As these defects coalesce under stress, the macroscopic response shifts from brittle failure to progressive softening, with reductions in Young’s modulus, cohesion and peak strength. Under triaxial or dynamic loading, chemically altered rocks display altered stress-strain paths, reduced dilatancy and changes in acoustic signatures. The coupling between fluid chemistry and mechanical loading governs damage evolution, permeability development and fracture propagation. These processes are critical to tunnel stability, underground storage integrity, hydrocarbon recovery and the conservation of cultural stone assets. Recent advances have improved our understanding of damage constitutive modelling, permeability-stress relationships and surface roughness evolution, offering predictive tools for safe design in chemically aggressive environments.

Research from Nature Portfolio

Recent studies have investigated the interplay between water-rock interactions and shear strength in sandstones under varied pH conditions. Using a custom meso-shear apparatus, three-dimensional scanning and electron microscopy, researchers demonstrated that both acidic and alkaline solutions reduce shear strength approximately linearly. Corrosion smooths fracture surfaces and diminishes surface irregularities, as quantified by parameters such as maximum height (Sh), root mean square deviation (Sq), area ratio (SA) and slope root mean square (S∆q). These findings establish a quantitative link between chemical aggressiveness and mechanical degradation, improving our capability to predict shear failure in chemically altered rock masses.

Mechanical Behavior of Rock Under Chemical Corrosion publication trend

The graph below shows the total number of articles in mechanical behavior of rock under chemical corrosion across all publications each year (not limited to Nature Index journals).

Technical terms

Chemical corrosion: Progressive alteration of rock minerals by reactive fluids, leading to dissolution or precipitation.

Porosity: Fraction of void space within a rock, governing fluid storage and transport.

Triaxial compression: Laboratory method applying confining and axial pressures to simulate subsurface stress.

Damage variable: Dimensionless parameter quantifying the extent of microstructural degradation.

Shear strength: Resistance of a rock to sliding failure along failure planes.

Fracture roughness parameters (Sh, Sq, SA, S∆q): Quantitative metrics describing morphology and irregularity of fracture surfaces.

References

1. The effect of chemical erosion on mechanical properties and fracture of sandstone under shear loading: an experimental study. Scientific Reports (2019).
2. Effect of Chemical Corrosion and Axial Compression on the Dynamic Strength Degradation Characteristics of White Sandstone under Cyclic Impact. Minerals (2022).
3. Study on Damage Statistical Constitutive Model of Triaxial Compression of Acid-Etched Rock under Coupling Effect of Temperature and Confining Pressure. Materials (2021).
4. Experimental Investigation of the Permeability and Mechanical Behaviours of Chemically Corroded Limestone Under Different Unloading Conditions. Rock Mechanics and Rock Engineering (2019).