In some situations a vertically installed ShapeArray needs to be buried, such as a during a tailings dam lift. In these situations, care should be taken to protect the ShapeArray installation so that the instrument remains functional after burial. Avoiding damage to the top of the ShapeArray's casing and cabling are of primary importance.
To mitigate the risk of damage to the ShapeArray installation, Measurand recommends enclosing the top of the installation with a concrete utility box and routing the ShapeArray cabling through PVC conduit. Steel plates should be included all around the bottom of the utility box to help disperse loading forces. Measurand also recommends surrounding the ShapeArray installation with geotextile and at least 1 foot (305 mm) of sand prior to loading any other materials over the installation.
As access to the top of the installation will no longer be possible after the burial, extra coils of slack cable should be available in the conduit at the top of the installation for strain relief. It is very important that this extra cabling remains loose and unrestrained (e.g. do not zip tie the coil together). It would also be a good idea to splice a surge protection device, such as an SAASPD, to cabling near the top of the installation.
The diagram below provides an example configuration that has been used by Measurand clients in the past to successfully protect an SAAV during a tailings dam lift.
Figure 1: Example configuration used to protect an SAAV during a tailings dam lift (all measurements in imperial units)