A.02 Pike Island L&D Monolith R33 and R34 River Wall Crack Stabilization Virtual Site Visit, Attachment 4.pdf

PIKE ISLAND L/D RIVER WALL MONOLITH CRACK STABILIZATION

SCOPE OF THE PROPOSED ACQUISITION:

The U.S. Army Corps of Engineers, Pittsburgh District, has a project that involves the repair and stabilization of a crack within two concrete river wall monoliths at Pike Island Locks and Dam, Ohio River, WV. The contract generally includes installation of a hollow core rock anchors, pressure grouting of the crack, and concrete demolition and placement. The major features of the requirements are identified below:

The contract specifically includes:

• Installation of temporary instrumentation for monitoring the cracks movement.

• Drilling, placing, tensioning and grouting of rock anchors.

• Demolition of a concrete section on top of the monoliths.

• Pressure grouting of the crack with hydrophobic grout.

• Replacement of multiple recess frames and covers.

• Drilling and placement of dowels for concrete repair.

• Placement of reinforcement for concrete repair.

• Placement of new concrete.

Pittsburgh District

Fig. 1: Overview of total area Project

Location of Monoliths R33/34

PIKE ISLAND L/D RIVER WALL MONOLITH CRACK STABILIZATION

SCOPE OF THE PROPOSED ACQUISITION:

The work is to be performed on the river side wall of the lock while the lock is in operation. There will be intermittent short term shutdowns of the river side lock permitted for specified critical operations of the construction. However, it is expected that the majority of the work can be completed while the lock remains in operation.

Access to the monoliths is limited due to their location in the project. The maximum load that can be carried across the miter gates to the work location is 100lb/sf. If needed, it is anticipated the contractor will move larger loads to the work site on the monoliths by utilizing river access by contractor supplied barge or with a contractor supplied crane. There will be a laydown area supplied on shore.

Disposal of concrete rubble will be required. Ferrous and all other construction waste material will be disposed of at commercially permitted facilities licensed to accept waste or recyclable materials as applicable.

Construction work will occur in direct proximity to waterway traffic and the operating locks and dam. The existing lock chambers are currently operated 24 hours a day, 7 days a week.

Pittsburgh District

Fig. 2: Overview of area of interest

Location of Monoliths R33/34

Fig. 3: Existing Crack in River Wall Monoliths R33 and R34 (Hand railing will be removed by project staff before start of work)

Pike Island L/D River Wall Monolith Crack Stabilization

Fig. 4: Crack on R33 View Facing Upstream. Fig. 5: View Facing Riverward Crack Passing Through Utility Box Recess and Terminating at Pump Well.

Fig. 6: View Looking Riverward Upstream Crack Crossing Bulkhead Slot and Monolith Joints of R33/34

Fig. 7: Buckled Grating and Framing to be Replaced

Fig. 8: Location of Crack Passing Through Utility Trench

Fig 9: View From Boat, River Side Face of Monolith R34 With Crack Running Down Chamfer of Monolith

Fig 10: View From Top of Wall River Side Face of R34 Monolith, With Crack Running Down Chamfer of Monolith