ABSTRACT
GPS positioning technology has advantages such as no need of keeping vision between measuring stations, not restrained by weather conditions, able to measuring the target’s 3D displacement and highly automated. The accuracy of short distance deformation monitoring can reach minor millimeter level[1], thus provides a new method for high-accuracy deformation monitoring of large construction and foundation pit. In Lishui Road project’s case the visibility condition in foundation pit construction site is bad and most datum marks can’t share vision, monitoring marks and datum marks are in different height, and also there is a across-river benchmark problem. To solve these problems above, this project take a monitoring plan using both modern and traditional measuring technology: using GPS technology to set up a 3D datum mark network, and using traditional measuring methods to monitor after the network is established[2].
