GSSI StructureScan Mini XT, Руководство пользователя

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Geophysical Survey Systems, Inc. StructureScan™ Mini XT
Manual
MN 70-813 Rev E 49
Empty PVC Conduit
The hyperbola identified by the orange arrow is an empty PVC conduit above a row of rebar. Note that
the dominate color for the PVC hyperbola is black while the rebar is white. The PVC wall is too thin for
GPR to image so we are reflecting off of the air void within the conduit. This produces a negative (black)
response since the energy is traveling from a higher dielectric (concrete) to a lower dielectric (air) in the
same manner as the void example earlier.
If the PVC conduit were filled with wire or liquid
the image would more closely resemble the rebar
image since there is now less air by volume in the
conduit.
GSSI recommends exercising extreme caution
when clearing out areas known or suspected to
contain conduits.