面向地面沉降长期自主监测的分布式光纤物联网系统

Long-term autonomous land subsidence monitoring using the internet of things based on the distributed optical fiber

地面沉降具有变化缓慢、趋势多变和范围广等特点。当前的传统测量法(包括水准测量、基岩标和分层标测量等)和InSAR、GPS等主要方法的监测存在不持续、分辨率低、不适应高动态及监测精度有限等缺陷,无法满足高精度、长期自主持续监测的发展要求。集信息采集与传输为一体的分布式光纤传感技术,具有沿光纤链路一维空间连续感知和传输外界信号的特点,且无需外部供电和不存在检测盲区,为地面沉降的大范围、长期持续监测提供了新方法和新途径。本文通过深入分析各种典型的地面沉降与分布式光纤传感技术,提出基于分布式光纤传感物联网、大数据和云计算的系统架构,对地面沉降过程中发生的温度、应力等物理变化进行监测,并将持续的监测数据上传云计算平台,再通过深层的数据挖掘与分析,研判沉降机理和沉降规律,可以对地面沉降进行及时和广泛的预测。

Land subsidence tends to change slowly and multifariously on a large scale. Current monitoring methods, including traditional techniques （e.g., geometrical leveling, bedrock marking, and layerwise marking）, interferometric synthetic aperture radar （InSAR） analysis, and GPS mapping, al have drawbacks in that they may be non-continuous, low resolution, low accuracy, or not suited to high dynamic, and so cannot meet the development requirements for very accurate and long-term autonomous monitoring. The Internet of Things, combined with widely distributed optical fiber networks, combines the efifcient col ection and transmission of information, has the characteristics of 1D continuous sensing along with the ifber link, transmitting the external signs, without external power supply and no blind monitoring ifeld. Therefore, it provides a new approach to the long-term autonomous monitoring of large-scale land subsidence. Through detailed analysis of several typical kinds of land subsidence, this article proposes a system based on the Internet of Things, fiber optic networks, big data, and cloud computing. This system would be able to monitor changes in temperature and strain produced by land subsidence, and upload the continuous monitoring data to the cloud. In addition, the system could be used to identify the mechanisms and rules that govern land subsidence using detailed analysis and data mining, and then to provide early warnings of likely land subsidence over a wide area.