The underground trolley station at San Diego State University (SDSU), a critical component of the new Mission Valley East extension (MVE), has been garnering local attention for several months as anticipation for its summer 2005 opening heightens. It has also captured the interest of the Consulting Engineers and Land Surveyors of California (CELSOC) which has selected the station’s mined tunnel as an Honor Award recipient in the 2005 Engineering Excellence Award competition. Winners will be recognized on
January 25, 2005
. In addition, the project will be part of a display at the State Capitol during national Engineer’s Week (
February 20-26, 2005
) and featured on the CELSOC Web site.
“The tunnel designer, Hatch Mott McDonald [HMM], is being recognized for innovations related to using the New Austrian Tunneling Methods in conglomerate geology and for the design methods which pushed the boundaries of engineering practice in this field,” explained Paul Jablonski, Metropolitan Transit System (MTS) CEO. “HMM is also being recognized for providing a designer's representative on site during the tunnel excavation and installation of the primary lining; the highest risk elements of the tunnel construction. MTS is very fortunate to have established a solid, proactive relationship with HMM one which has made the SDSU station a reality and the MVE extension possible.”
As one of four new stops being built on the $496 million MVE extension, the SDSU underground trolley station holds the distinction of featuring the first subterranean trolley station and tunnel in San Diego. Logistically, the trolley platforms are located 25-feet below the facility’s mezzanine level and 40 to 60-feet below street level. The tunnel was built using both the cut and cover method for 3,000 feet and the New Austrian Tunneling Method (NATM) for 1,000 feet. In the New Austrian Tunneling Method, arched portions of the tunnel are excavated in short segments using conventional equipment, and the tunnel walls are immediately shot-creted for support. It is for this latter tunnel that the facility has been recognized by CELSOC.
On a national level, the MVE project has also been selected as one of CELSOC’s nominees in the American Council of Engineering Companies (ACEC)’s Engineering Excellence Awards competition.