Experimental Study on the Strength and Failure Mechanism of Hollow Hot Dry Rocks Under Brazilian Splitting Tests

The investigation into the effects of acidizing treatment on the mechanical property of hot dry rocks (HDR) is beneficial for our understanding of the fracturing and stimulation mechanisms in HDR reservoirs. In this article, Brazilian disk tests were first carried out for hollow hot dry rocks with different internal diameters after acidizing treatments. The influences of acidizing treatments on the physical properties, tensile strength, and failure patterns of hot dry rock specimens were presented. Besides, the effects of the diameter of the internal hole on the peak load and failure patterns of the hot dry rock specimens were also investigated. The peak load decreases with the increase in the internal diameter. The results indicated that the acidizing treatments can dissolute the minerals, decrease rock mass, and tensile strength. The investigation of failure patterns demonstrated that the acidizing treatment is beneficial for the fracturing of hot dry rocks. The present study can provide some basic and theoretical data for the development of geothermal reservoir.