Anti-drainage Construction Technology of Road Diversion Tunnel Excavation in Water-rich Area
Surge water is one of the most prevalent ailments afflicting tunnel construction,exerting a profound influence on the safe and efficacious construction of tunnels.Consequently,our study was undertaken on the anti-drainage construction technology of highway rerouting tunnels excavated in water-rich areas.In this study,the county highway reroute tunnel in Lianghekou Hydropower Station was selected as the research object.Initially,the geological and water influx situation was determined,the uneven area in the tunnel was addressed,and the blind tube was installed according to the appropriate spacing.Subsequently,the water-sealing strips were placed in the construction joints and settlement joints,and then the waterproofing board and water-sealing strips were installed.Concrete was then poured to achieve the reroute tunnel excavation and anti-drainage,following numerous adjustments.Finally,a tunnel model was constructed with the finite element software FLAC3D.The anti-drainage effect of blind tube spacing and the utilization of water-seals following construction was calculated.The findings indicate that a reduction in blind tube spacing can diminish the extent of the shear plastic and tensile plastic zones within the tunnel,thereby preventing significant deformation of the surrounding rock.Conversely,an increase in blind tube spacing can curtail water inflow.Following a comprehensive assessment,the optimal blind tube spacing was determined to be 4m,as this configuration exhibited superior construction performance.Additionally,the utilization of water-seals has been shown to facilitate effective drainage even under elevated inlet pressure,thereby enabling the effective management of drainage in water-rich highway reroute tunnel excavations.
water-rich regionroad diversiontunnel excavationanti-drainageconstruction technologyFLAC3D finite element