Thermal shock on tensile behaviour of granite is highly important for understanding of fracturing mechanism in hot dry rock. The effects of heating and water-cooling treatment (HWCT) on tensile behaviour of granite were investigated in this work. The granite samples were first heated to different predetermined temperatures and then rapidly cooled by water. The Brazilian split tests were carried out on the HWCT samples, and the strain gauges were used to measure the evolution of tensile deformation. With the increasing of heating temperature, the tensile stress–strain curves change from linear to nonlinear, the axial tensile strain corresponding to failure point increases, and the tensile strength and tensile elastic modulus undergo a slight increase to decrease as the temperature increases. Finally, the mechanical properties under tensile condition were compared with those under compressive condition. Below 300 °C, the temperature has slight effect on both tensile and compressive strengths. Above 300 °C, the tensile properties decrease significantly after heating temperature threshold of 300 °C, while the heating temperature threshold for compressive properties is 500 °C. The thermal shock has a greater effect on tensile strength than on compressive strength.

热冲击对花岗岩拉伸行为的影响对于理解干热岩中的压裂机制非常重要。在这项工作中研究了加热和水冷处理（HWCT）对花岗岩拉伸行为的影响。首先将花岗岩样品加热到不同的预定温度，然后用水快速冷却。对 HWCT 样品进行了巴西劈裂试验，并使用应变仪测量拉伸变形的演变。随着加热温度的升高，拉伸应力-应变曲线由线性变为非线性，失效点对应的轴向拉伸应变增加，拉伸强度和拉伸弹性模量随着温度的升高略有增加而降低。最后，将拉伸条件下的力学性能与压缩条件下的力学性能进行比较。低于 300 °C，温度对拉伸和压缩强度都有轻微影响。300°C以上，在300°C的加热温度阈值后拉伸性能显着下降，而压缩性能的加热温度阈值为500°C。热冲击对拉伸强度的影响大于对压缩强度的影响。