Proportioning optimization of transparent rock-like specimens with different fracture structures

Area of Science:

• Geotechnical Engineering
• Materials Science

Background:

• Understanding internal fracture and seepage evolution in rock masses requires effective visualization techniques.
• Transparent rock-like specimens offer a promising medium for such studies, but their optimization is critical.

Purpose of the Study:

• To investigate the influence of composition (resin, hardener, accelerator ratios) and freezing duration on the mechanical properties and failure mechanisms of transparent rock-like specimens.
• To establish principles for proportioning optimization of these specimens, particularly those with varying fracture structures.

Main Methods:

• Orthogonal experimental design was employed to systematically vary the ratios of resin, hardener, and accelerator, as well as freezing duration.
• Mechanical properties (uniaxial compressive strength, tensile strength, elastic modulus) and failure modes under uniaxial compression were analyzed.
• A method for inducing controlled fractures was developed and applied.

Main Results:

• Increased accelerator ratio and freezing time generally decreased mechanical strength and elastic modulus.
• Hardener ratio showed a complex effect, initially increasing then decreasing mechanical properties.
• Failure modes shifted from bulging to bursting with higher hardener and accelerator content.
• Specimens with intact, embedded, and random 3D fractures were successfully prepared.

Conclusions:

• The study provides a framework for optimizing the composition of transparent rock-like materials for specific fracture characteristics.
• Findings offer theoretical guidance and technical support for visualizing fracture and seepage evolution in rock masses.
• This research enhances the application of transparent rock-like materials in geotechnical studies.