测绘技术在大江截流及二期围堰的应用

Application of New Survey Technique to Construction of Cofferdams

三峡工程二期上、下游横向围堰与混凝上纵向围堰共同形成二期基坑，测绘工作要求很高。为此，配置了两台多功能全站仪，可自动记录观测数据、计算三维坐标和预置放样数据；还配有DIOR3002无反射棱镜测距仪、激光准直经纬仪等先进测绘仪器，实施了TCA1100电子全站自动化测量、GPS实时差分自动化测量等先进测绘技术，可有效地进行水下测绘工作。

The second stage construction area on the main river bed is formed by the second stage up & downstream transverse cofferdams and the longitudinal con crete cofferdam.The construction needs high efficient and high precise surveying technique.For this reason,a batch of advanced survey instruments, such as mul tipurpose total station instruments,DIOR 3002 distance meter and laser alignment theodolite, have been purchased, in order that the automatic surveying,including mapping underwater, by TCA 1100 electronic total station instruments and GPS re al time adjustment technique can be realized.