Study On New Environment-Friendly Structure Of Highway Tunnel Construction Technology

With the rapid socio-economic development, environmental protection, security and thrifty in the construction of high-grade highway tunnel are increasingly appreciated by the majority of road builders, higher requirements are put forward in the landscape and environmental protection of highway. Although compared to other forms of structures, tunnel has environmental advantages, the construction and operation of the tunnel will inevitably change the original state of the environment and may make the environment be not conducive to the direction of human existence, or cause environmental pollution. Thus in the process of building the tunnel, new technologies conducive to environmental protection should be studied.This paper was based on the engineering practice of No.1 hole, Tiger Mountain tunnel of studio contract section H5 of HongAn (Xiang Yu sector) to ShangGuan bridge which belongs the west inter-provincial highway access road from Chongqing to Changsha. Firstly, a detailed exposition was given of the environmental advantages, structural analysis, design and construction to the shed-tunnel structure. Finite element software FLAC was used to analyze the slope structure stability by numerical simulation, thus some conclusions were obtained, two-stage excavation of which stress concentration only exists at the foot of the slope had less effect to the slope stability, in the course of construction, appropriate treatment measures were taken here to ensure the slope stability and the construction safety is more reliable, as long as the shed-tunnel structure was built up with temporary slope stability, the entire slope would be permanently safe, so the amount of excavation was greatly reduced, original ecology of the surrounding natural environment was protected and the disturbance of natural geological body was significantly reduced, thus possibility of geological hazards was also reduced; Secondly, the engineering geological conditions of the Tiger Mountain tunnel was introduced and the engineering characteristics, construction technology and main points of the construction of advanced tunnel entrance construction method were expounded, this method adopted the principles of naturally entering the hole, as long as the hole locations and entering program were reasonably determined, correct arrangement of construction steps and a number of ancillary construction steps for entering the hole ahead were adopted, hidden troubles of the tunnel hole would be effectively solved and the natural environment of the hole was protected, realizing'early in and late out' Finally, organizational design of implemental construction was introduced, mainly including the methods,processes, quality management and assurance system and measures of the tunnel construction and so on.