干、湿沙层对岩石受力微波辐射影响的实验对比

摘要 在天空冷背景下，通过实验模拟卫星对地观测，研究盖层对岩石受力过程中微波辐射的影响规律及影响机理.实验以花岗岩及覆被干、湿沙层为例，采用卧式压力机和C波段微波辐射计对岩石受力过程中松散盖层对辐射变化的影响规律进行观测.实验结果表明:花岗岩弹性变形阶段的微波辐射变化与载荷具有很好的同步性，相关系数达0.94，微波亮温变化量为0.015K/MPa.当岩石观测面铺设2.5cm厚的干沙层或湿(含水)沙层时，其对受力岩石微波辐射影响存在差异:1) 干沙层对岩石受力过程中的微波辐射变化量无显著影响;2) 含水沙层显著削弱了微波辐射计所接收到的岩石中由力引起的微波辐射变化信号.
Abstract：Considering the working conditions of satellite sensors in earth observation， the loading experiments of rock under the condition of cold sky background were carried out. The influence of cover layers on microwave radiation from loaded bare rock in elastic phase is analyzed， and the influence mechanism is discussed as well. The horizontal loading machine and C band microwave radiometer were applied for observing the microwave radiation from the stressed granite samples covered by different materials: dry or humid silver sands. The experimental results show good synchronicity between the microwave radiation and the loaded stress in the elastic deformation phase of granite samples， which with the correlation coefficient of 0.94 and the microwave brightness increases by 0.015K/MPa. When covered by dry or humid sands(with layer thickness of about 2.5cm)， the characteristics of affected microwave radiation from the stressed rock are much different: 1)the dry sand has no obvious influence on the affected microwave radiation from stressed rock; 2)the humid sand weakens the signals received by microwave radiometer significantly.