PRACTICAL APPLICATIONS OF GPS FOR GIS AND CIVIL ENGINEERING

The US Department of Defense's constellation of 24 Navstar satellites now provides civil engineers with a very powerful, fast and Versatile positioning system, With suitable controls and corrections it can also be extremely accurate, In addition to basic survey and setting-out fu nctions, the electronic nature of GPS also makes it ideally suited for GIS data collection, This paper introduces the basic techniques assoc iated with GPS and discusses its practical application in civil engine ering, with particular reference to the Channel Tunnel Rail Link proje ct and motorway profiling.