GEODETIC WORKS IN MICRO TUNNELING PROJECTS EXCAVATED BY PIPE-JACKING METHOD

Abstract

Installation techniques of pipes line, such as water, sewerage, gas etc. are changed nowadays. Because of conventional installation of pipes in trench has many disadvantages, such as disruption to traffic flow, loss of access, noise, additional safety and technical problems with other buried services, trenchless pipeline technologies are used widely nowadays. Settlements of the road surface are not to be expected as well as road repair work is not necessary along the pipeline for trenchless installation. There have been considerable advances in trenchless pipeline installation techniques during the last decade. Pipe jacking, that is a method to install a pipeline section trenchless from the jacking shaft to the target shaft, is one of these trenchless techniques. The problems caused by trench techniques and their associated costs can be reduced with pipe jacking method. Pipe jacking method can be used in micro tunnelling technology. Tunnel survey methods are also changed continuously depending on changes occured in tunnel excavation methods. As a result of considerable advances in tunnel survey methods, there is no need to make geodetic measurements in the tunnel. All geodetic measurements can performed out of the tunnel automatically. Especially in micro tunnels, geodetic measurements can not performed in tunnel, because the size of it is not suitable to make measurements in tunnel. Because of the control of micro tunnel alignment is performed by computer supported, accuracy of guiding of the tunnel machine has been increased horizontally and vertically. Because of increased work safety, accidents, that will be in tunnel excavation works, have been decreased to minimum level by the new techniques developed in tunnelling. Because of the automation in tunnel works, persons, who work in tunnel project, and the equipments, that are used in tunnel project have been decreased, as a result of this, economical advantages have been obtained.