U.S. ARMY CORPS OF ENGINEERS SERVICE BASE MOORING REPLACEMENT

St. Louis, Missouri

Massman built this project to replace and enlarge the aging regional mooring facility for the U.S. Army Corps of Engineers Service Base in downtown St. Louis. The existing timber pile mooring clusters were decomposing and had become unsuitable for securing barges. In addition, decades of fluctuating river elevations had deposited drifted debris for hundreds of yards along the riverbank, rendering the existing 1,100 feet of riverfront area insufficient to store all of the equipment used by the Corps.

The initial demolition work included the removal and disposal of 14 timber pile clusters, four pipe-pile dolphins, and the drift and debris along the riverbank. Next, the existing timber trestle was extended by installing eight new pipe piles that were socketed into rock. Along with the new piling, additional structural steel and concrete decking was placed to complete a 45-foot extension.

Twenty-two heavy-duty pipe pile tripods were installed by drilling up to 20 feet into the existing rock, grouting each socket, and placing concrete on the top of the piling. The original design called for five-foot sockets with rock anchors extending 33 feet below the sockets. Increasing the depth of the sockets and eliminating the rock anchors saved considerable time on the project during design. The tripods were completed by welding bracing and cap plates at the top of each tripod.

To complete the project, Massman installed 28 dock barges following tripod installation. Each barge was secured with a capture frame that encircled the vertical pile on each of the tripods. A water supply system and electrical system were then installed along the trestle and the dock barges.