Study On The Formation Mechanism And Control Technology Of Seepage Disease In The Lishi Loess Tunnels Of Li-Jun Expressway

The water seepage in Lishi loess tunnel is studied in this paper.The characteristics of the leaking water in the loess highway tunnel are investigated by site investigation.Based on the analysis of the causes of the disease,the response mechanism in the construction stage and the operation siage was simulated via finite element Mathod.Meanwhile,treatment tcchnolngies are put forward.The resarch in this paper can provide reference for similar project.The main research results are as follows:1)By the field investion,it's found that those diseases always occur at are construction joints,especially the tunnel vault poslitions of circulur construction joints,hance nearby mid-partilions and mid-partitions on the opening.Construction period is the key point to control the seepage which occurs in operation period,Arch tunnel is more prone to leakage because of is inherent defects.2)The principal of frequent measurement,immediate follow-up and timely support should be followed on the construction of mid-partitions,tunnel hance positions of left and right tunnels and arch foot cohesion.On the construction period,drainage system should be set on the left tunnel,seepage detection should be enhhanced,as well as concrete with high anti-permeability resistance should be used.meanwhile,the prevention and leakage should be well controlled.3)Try to avoid the construction of the tunnel during the rainy season.The reinforcement of the surrounding rock can signifieantly reduce the risk of the leakage and prolong the service life of the tunnel.The water damage area in the operation of the tunnel is mainly concentrated in the vaults and the mid-partitions,which is similar with the research results of the leakage in Lijun highway.4)Through the study on formation mechanism of seepage diseases on loess multi-arch tunnel,control technology were discussed.Modular production and modular construction of the existing integral pouring mid-partitions were completed.A design and construction technology of mid-partition for multiple-arch tunnel with modular waterproof and drainage was brought up?...