GPS测量在城市地面沉降监测中的应用研究

APPLIED RESEARCH OF MONITORING THE URBAN LAND SUBSIDENCE USING GPS SURVEYING

为了研究用高精度的GPS高程测量来监测城市地面的沉降变化 ,在N市建立了GPS基准网和监测网。在观测中采取了一定的措施 ,以获得高精度的高程分量。顾及到对流层延迟的影响 ,采用Saastamoinen模型来计算对流层延迟的干分量 ,用随机过程模型来估计对流层延迟中的湿分量变化。基线解算采用了高精度解算软件Bemese ,网平差使用了PowerADJ科研版。实际算例表明 ,采用GPS技术进行城市地面沉降监测 ,获得了毫米级的高程精度 ,能够满足城市沉降监测的需要。

Abstract:In order to monitor the change of urban land subsidence by high accurate GPS height surveying technique,a GPS fiducial network were established in N city.Some measures were taken during GPS observation in order to obtain the high precise height component.Considering the affect of tropospheric refraction,Saastamoinen model was adopted in the data processing of the dry component part of the tropospheric delay.The wet component change of the tropospheric delay was estimated by using stochastic processes model.The high precision Bernese software was used to resolve the baselines.And the network adjustment was carried out with PowerADJ scientific research edition.It is verified by the practical example in this paper that the mm-level measuring precision was achieved when the urban land subsidence was monitored using GPS surveying.The precision of GPS surveying canstisfy the reguirement of the wrban land subsidence.