Study On Construction Technology Of The Soft Rock Tunnel Passing Througy Existing Railway

With the development of traffic engineering, more and more high-way and railway tunnels, especially, urban underground engineering, are built. It is an object realized for engineers that both safy and economic construction schemes, as well as rapid, are used to meet certain conditions.In viture of the cover-up character of tunneling and other underground engineering and various geologic conditions, so construction strategies, methods and technologies adopted must be very fit for it. a step and multi-step excavation method are often applied, while single side wall and double side wall are more used to meet big section tunneling.In this paper, aimed at Xinquercha tunneling, in order to safely pass through existing Longhai railway during tunnel excavation, all kinds of construction technologies are expatiated in details. By means of the numerical simulation and spot measure, the safety and reliability to use CRD excavation method to building shallow big-span double-line tunnel under existing vibrant train load are tested.