Granite at a high temperature can cause a decrease in strength and cracking when exposed to a rapid cooling shock. Therefore, the cooling shock method can be considered as a potential cracking technology to improve the energy exploitation efficiency. The thermal cracking damage of high-temperature granite after cooling shock induced by different low-temperature refrigerants were studied. Firstly, granite samples were heated to different targeted temperatures (i.e.100, 300, 500, and 700 °C). Then, all heated samples were respectively soaked in these refrigerants with different temperatures (i.e. 20, 0, − 10, − 20 and − 30 °C) or cooled in the air condition as a reference. When the cooling process ends, the effects of cooling shock on the strength characteristics and failure modes of high-temperature granites were respectively observed by acoustic wave, uniaxial compression test and the acoustic emission (AE) test. Some main conclusions are: (1) The high temperature granite p-wave velocity tends to decreases with the refrigerant temperature decreases. (2) The lower CaCl₂ solution temperature is, the lower the peak strength. The specific performance is that the higher granite temperature, the more obvious the granite strength decreases after the cooling shock. (3) The curves under different temperature gradients performs from a “single/double peak” to a “multipeak” as the refrigerant temperature decreases. (4) The failure modes of granite subjected to different temperature gradients are obviously different, of which X-type shear failure is shown above 500 °C. These studies verify the strong effect of cooling shocks on high-temperature granite. Scholars can draw on the experience of cooling shock technology in the geothermal development of late-stage high-temperature rock masses.

暴露于快速的冷却冲击下，高温下的花岗岩会导致强度降低和开裂。因此，冷却冲击法可被认为是提高能量利用效率的潜在裂解技术。研究了不同低温制冷剂引起的冷却冲击后高温花岗岩的热裂损伤。首先，将花岗岩样品加热到不同的目标温度（即100、300、500和700°C）。然后，将所有加热的样品分别浸入这些具有不同温度（即20、0，-10，-20和-30℃）的制冷剂中，或在空气条件下冷却作为参考。冷却过程结束后，通过声波，单轴压缩试验和声发射（AE）试验分别观察了冷却冲击对高温花岗岩强度特性和破坏模式的影响。主要结论如下：（1）随着制冷剂温度的降低，高温花岗岩的p波速度趋于减小。（2）低级氯化钙₂溶液温度是，峰值强度越低。具体表现是花岗岩温度越高，冷却冲击后花岗岩强度下降越明显。（3）随着制冷剂温度的降低，不同温度梯度下的曲线从“单峰/双峰”到“多峰”。（4）花岗岩在不同温度梯度下的破坏模式明显不同，其中500℃以上出现X型剪切破坏。这些研究证实了冷却冲击对高温花岗岩的强大影响。学者可以借鉴冷却冲击技术在后期高温岩体地热开发中的经验。