【摘要】 将分布式光纤传感技术引入滑坡监测,既可得到整个滑坡体的概要特征,又能提高监测效率。FBG与BOTDR是两种最具代表性的分布式光纤传感技术,FBG通过测量其反射光波长的变化获得应变或温度值。BOTDR通过测定后向布里渊散射光的频移实现分布式温度、应变测量。FBG传感器灵敏度高,但只能实现离散点的准分布式测量,BOTDR可实现分布式、长距离、不间断测量,但其空间分辨率不高。笔者提出FBG与BOTDR联合监测滑坡的方案。在巫山残联滑坡,在整个滑坡体上铺设监测光纤,利用BOTDR获得整个滑坡体的概要信息;在滑坡体变形的关键部位———变形缝安装FBG传感器,获得某些关键部位的应变信息,从而实现由点到线再到面的监测,获得滑坡体较完整的应变信息。更多还原

【Abstract】 Using the distributed optical fiber sensing technology in landslide monitoring,the main specialty of the landside may be obtained and the monitoring efficiency may be improved.Fiber bragg grating(FBG) and brillouin optic time domain reflectometry(BOTDR) are two kinds of the most representative distributed optical fiber sensing technologies.FBG obtains the strain or the temperature by measuring the change of the reflected light wave length.BOTDR realizes the distributed temperature and strain measurement by measuring the shift size of backward Brillouin scattered light.The sensitivity of FBG sensor is high but it only measured the discrete distributed sensing spots.The BOTDR sensing part is the optical fiber.It may realize the long distance,the uninterrupted and distributed monitor.But for its technical limit,the measurement distance resolution of BOTDR is not high.Based on this,the authors put forward a notion,that BOTDR combines with FBG to monitor landslide.In Canlian landslide located in Wushan,the monitoring optical fiber was laid on the entire landside and BOTDR was used to obtain the outline information of it.FBG was installed at the certain essential spots,the strain fissures,to obtain their strain information.Thus the landside can be monitored from dot to line and future to surface.Finally the completed strain information of the landslide can be obtained.更多还原