Rehabilitation of Union Pacific Railroad Tunnel, Ryndon, Nevada

Over a three-year period, a section of railroad tunnel, near Ryndon, NV, had undergone significant deformation of the tunnel lining due to inadvertent undermining of the footings during removal of concrete invert struts to improve vertical clearance and rectify a series of mud fouling problems in the track structure. Emergency response steel invert struts were successful in arresting liner movement. However, seepage and resultant mud pumping remained a serious problem that would influence the long-term stability of the tunnel. The permanent liner stabilization program consisted of the installation of high capacity minipiles and tieback anchors along the affected tunnel length, coupled with a program of enhanced drainage. This paper presents the design and implementation of the fast track rehabilitation program.