加热方式对花岗岩力学性能影响的试验研究

Effects of heating methods on the mechanical properties of granite

为了对比微波加热和传统加热对花岗岩力学特性的影响,采用微波加热和传统加热两种方式对花岗岩进行了不同温度加热处理(分别是300、500、600、800℃),对加热后的试样分别进行密度、纵波波速测量和单轴压缩试验,分析了两种加热方式下密度、波速、应力应变曲线、单轴抗压强度和弹性模量随温度变化规律,讨论加热方式对花岗岩性能的影响。结果表明:两种加热方式下,花岗岩的密度、波速、单轴抗压强度和弹性模量均随加热温度升高而降低,并且在500~600℃范围内降低速率最大。在相同加热温度下,微波加热会使花岗岩的密度、波速、单轴抗压强度和弹性模量下降得更多。两种加热方式诱导的差异性随加热温度升高而增加。相比于传统加热,微波加热时间更短,一般仅为传统加热时间的1/7,微波加热在降低花岗岩性能方面效率更高。

To compared the microwave and conventional heating effects on the mechanical properties of granite,microwave and conventional heating methods were performed to heat granite specimens at different temperature(300,500,600,800℃).After heating,the density,P-wave velocity,and uniaxial compression tests were performed.The effects of heating temperature on the density,P-wave velocity,stress-strain curve,uniaxial compression strength and elastic modulus were analyzed under the two heating methods.The microwave and conventional heating effects on the granite properties were discussed.The results show that under the two kinds of heating methods,the density,P-wave velocity,uniaxial compression strength,and elastic modulus all decrease as heating temperature increases,and the reduction rate is the highest from 500 to 600℃.Under the same heating temperature condition,the decreasing extent in density,P-wave velocity,uniaxial compression strength,and elastic modulus of granite after microwave heating is higher than that after conventional heating.The difference induced by the two heating methods increases as heating temperature increases.Compared with conventional heating,the microwave heating time is shorter,generally only 1/7 of the conventional heating time.Therefore,microwave heating is more efficient in degrading granite performance.