Experimental Study on the Mechanical Properties of Rock Fracture after Grouting Reinforcement

Abstract

Grouting reinforcement plays an important role in repairing fractures and improving the strength of the surrounding rock. To address practical engineering challenges such as caving and chip off-falling of surrounding rock in deep roadways, normal splitting was adopted to prefabricate fractures on rock samples gathered from underground coal mines. This was done to better match the rock fracture specimen with actual conditions. Based on the elementary unit of a fracture surface, systematic experiments were conducted on the tensile properties of rock fractures after grouting reinforcement, and the shear properties were studied after considering the presence of gas. As per the results, the tensile strength of rock fractures increased with the increase in viscosity of grout, but the overall tensile strength was relatively low. The overall tensile effect of surrounding rock was improved less by grouting approach. When the presence of fracture gas in grouting was considered, the peak shear strength of fractures after grouting was 8.34–29.9% less than that without considering the fracture gas. The cemented pore surface produced by unsaturated cementation in the grouting reinforcement was the main cause of reduction in cohesion and frictional angle of rock fractures. The conclusions of this study have great significance for guiding engineering grouting and evaluating the grouting effect.

Coal Mining Sustainable Development: Economics and Technological Outlook

“…Liu et al [7] explore the inverse problem of rock mechanics-improving the strength of the rock surrounding deep underground constructions by grouting reinforcement, which is important for labor safety and accidents prevention. The article displays the results of the series of systematic experiments aimed on discovering the tensile and shear strength properties of rock after grouting reinforcement, including studies considering the presence of gas.…”

Influence of Different Grouting Parameters on Mechanical and Strain Energy Characteristics of Different-Length Fractured Limestone in a Coalfield North of Yellow River: A Numerical Study Based on Particle Flow Code

“…An analysis model of grouting seepage and stability of roadway surrounding rock after reinforcement was established. Liu et al [15] compared the closure strength and shear strength of the crack surface of the rock mass before and after grouting reinforcement and obtained the change rule of the mechanical properties of the rock mass crack before and after grouting. Wang et al [16,17] analyzed the influence of grouting strength and bonding force on the grouting reinforcement effect through static and dynamic mechanical tests of rock mass after grouting reinforcement.…”

Study on the Macro-Micro Mechanical Properties of Grout Consolidated Coal under Different Loading Rates

“…When drilling and sealing holes, grouting reinforcement technology is mostly used for treatment [6]. The sealing slurry penetrates and diffuses along the cracks around the hole, and cements within the coal to form a consolidated body [7][8][9]. This structure can enhance the compressive strength of the coal body around the hole and improve the sealing effect [10,11].…”