Figure 12 - Model 4810 Contact - Geokon 4820 Instruction Manual

11
2.2.2.2 Installation on Existing Structures
The lugs welded to the edge of the cell can be used to hold the cell against the structure
using nails, lag bolts, tie wire, etc. Even if the surface is smooth, but especially when the
surface is rough or irregular, a mortar pad between the cell and the structure is required.
See Figure 12.
Pipe Straps & Conduit
Concrete Nails
(4 places)
Zone with large aggregate removed
Mortar Pad
Side View Front View
Figure 12 - Model 4810 Contact Pressure Cell Installation
Use the lugs on the cell as a template to locate the position for drilling holes for the
installation of expanding anchors or install the anchors nearby and use wire to hold the
cells in place. Alternately, the cell may be nailed in place using the lugs as a guide.
Mix up some quick-setting cement mortar or epoxy cement. Trowel this onto the surface
then push the cell into the cement so that the excess cement extrudes out of the edges of
the cell. Hold the cell in place while the cement sets up then complete the installation by
adding the lag bolts (using the expansion anchors) and tightening or nailing the cell in
place. Protect the cell, transducer housing, and cable from direct contact with large
chunks of rock by covering them with a fine grained fill material from which all pieces
larger than about 10 mm (0.5") have been removed. This material is kept near the cell and
cable as the fill is placed. Additional cable protection can be achieved by using metal
conduit strapped to the surface of the structure.