Buried Utilities GPR

[et_pb_section admin_label=”section”][et_pb_row admin_label=”row”][et_pb_column type=”4_4″][et_pb_text admin_label=”Text” background_layout=”light” text_orientation=”left” use_border_color=”off” border_color=”#ffffff” border_style=”solid”]

Buried Utilities GPR

Examples of GPR profiles demonstrating identification of pipes with various contents

GPR  is routinely used to locate precisely a wide variety of buried utilities. The antenna of choice is at 400 MHz. In the examples shown, the utility, commonly a pipe, is located at the apex of the hyperbola in the radargram. The color banding of the hyperbola may provide information about the contents of the pipe.

[/et_pb_text][/et_pb_column][/et_pb_row][et_pb_row admin_label=”Row”][et_pb_column type=”1_2″][et_pb_divider admin_label=”Divider” color=”#ffffff” show_divider=”off” height=”100″ disabled=”off” disabled_on=”on||” divider_style=”solid” divider_position=”top” hide_on_mobile=”on”] [/et_pb_divider][et_pb_text admin_label=”Fig. 1. ” background_layout=”light” text_orientation=”left” use_border_color=”off” border_color=”#ffffff” border_style=”solid”]

Fig. 1. 400 MHz GPR profile showing three hyperbolas indicating three pipes located at the apices of the hyperbolas and oriented at an angle to the profile. The middle diffraction hyperbola has a strong, upper black band signaling that this diffraction has a negative phase polarity. This indicates that the pipe is air-filled (empty) PVC (known to be 8“ in diameter).*

[/et_pb_text][/et_pb_column][et_pb_column type=”1_2″][et_pb_image admin_label=”Image” src=”http://geoscy.com/wp-content/uploads/2016/03/48.png” show_in_lightbox=”off” url_new_window=”off” use_overlay=”off” animation=”fade_in” sticky=”off” align=”center” force_fullwidth=”off” always_center_on_mobile=”on” use_border_color=”off” border_color=”#ffffff” border_style=”solid”] [/et_pb_image][/et_pb_column][/et_pb_row][/et_pb_section][et_pb_section admin_label=”Section” fullwidth=”off” specialty=”off” transparent_background=”off” background_color=”#eaeaea” allow_player_pause=”off” inner_shadow=”off” parallax=”off” parallax_method=”off” padding_mobile=”off” make_fullwidth=”off” use_custom_width=”off” width_unit=”on” make_equal=”off” use_custom_gutter=”off”][et_pb_row admin_label=”Row”][et_pb_column type=”1_2″][et_pb_image admin_label=”Image” src=”http://geoscy.com/wp-content/uploads/2016/03/49.png” show_in_lightbox=”off” url_new_window=”off” use_overlay=”off” animation=”fade_in” sticky=”off” align=”center” force_fullwidth=”off” always_center_on_mobile=”on” use_border_color=”off” border_color=”#ffffff” border_style=”solid”] [/et_pb_image][/et_pb_column][et_pb_column type=”1_2″][et_pb_divider admin_label=”Divider” color=”#ffffff” show_divider=”off” height=”100″ disabled=”off” disabled_on=”on||” divider_style=”solid” divider_position=”top” hide_on_mobile=”on”] [/et_pb_divider][et_pb_text admin_label=”Fig. 2. ” background_layout=”light” text_orientation=”left” use_border_color=”off” border_color=”#ffffff” border_style=”solid”]

Fig. 2. 400 MHz GPR profile across a road showing one bright hyperbola indicative of a pipe located at its apex.  The diffraction hyperbola has a white upper band which means a positive phase polarity. This signals either that the pipe is full of water or is composed of metal. Both alternatives, at this location, imply the pipe is a water main.*

[/et_pb_text][/et_pb_column][/et_pb_row][/et_pb_section][et_pb_section admin_label=”Section” fullwidth=”off” specialty=”off”][et_pb_row admin_label=”Row”][et_pb_column type=”1_2″][et_pb_divider admin_label=”Divider” color=”#ffffff” show_divider=”off” height=”50″ disabled=”off” disabled_on=”on||” divider_style=”solid” divider_position=”top” hide_on_mobile=”on”] [/et_pb_divider][et_pb_text admin_label=”Fig. 3. ” background_layout=”light” text_orientation=”left” use_border_color=”off” border_color=”#ffffff” border_style=”solid”]

Fig. 3. 400 MHz GPR with several bright, stacked diffraction hyperbolas. Several pipes must be located at the apex of this hyperbola cluster. Note dipping left upper edge of a trench above and to left of the hyperbolas. Survey site is adjacent to an industrial building. The bank of conduits feeds into the building. *

[/et_pb_text][/et_pb_column][et_pb_column type=”1_2″][et_pb_image admin_label=”Image” src=”http://geoscy.com/wp-content/uploads/2016/03/50.png” show_in_lightbox=”off” url_new_window=”off” use_overlay=”off” animation=”fade_in” sticky=”off” align=”center” force_fullwidth=”off” always_center_on_mobile=”on” use_border_color=”off” border_color=”#ffffff” border_style=”solid”] [/et_pb_image][/et_pb_column][/et_pb_row][/et_pb_section][et_pb_section admin_label=”Section” fullwidth=”off” specialty=”off” transparent_background=”off” background_color=”#eaeaea” allow_player_pause=”off” inner_shadow=”off” parallax=”off” parallax_method=”off” padding_mobile=”off” make_fullwidth=”off” use_custom_width=”off” width_unit=”on” make_equal=”off” use_custom_gutter=”off”][et_pb_row admin_label=”Row”][et_pb_column type=”1_2″][et_pb_image admin_label=”Image” src=”http://geoscy.com/wp-content/uploads/2016/03/51.jpg” show_in_lightbox=”off” url_new_window=”off” use_overlay=”off” animation=”fade_in” sticky=”off” align=”center” force_fullwidth=”off” always_center_on_mobile=”on” use_border_color=”off” border_color=”#ffffff” border_style=”solid”] [/et_pb_image][/et_pb_column][et_pb_column type=”1_2″][et_pb_divider admin_label=”Divider” color=”#ffffff” show_divider=”off” height=”50″ disabled=”off” disabled_on=”on||” divider_style=”solid” divider_position=”top” hide_on_mobile=”on”] [/et_pb_divider][et_pb_text admin_label=”Fig. 4.” background_layout=”light” text_orientation=”left” use_border_color=”off” border_color=”#ffffff” border_style=”solid”]

Fig. 4. 3D GPR radargram of a 50 ft x 40 ft area showing several utility lines (bright white lines) on a horizontal slice at a depth of 4 ft. Data collected with a 400-MHz antenna. Utility lines probably dip at a slight angle and so would be apparent on other depth slices.*

[/et_pb_text][/et_pb_column][/et_pb_row][/et_pb_section][et_pb_section fullwidth=”off” specialty=”off” admin_label=”Section”][et_pb_row admin_label=”Row”][et_pb_column type=”4_4″][et_pb_text admin_label=”Text” background_layout=”light” text_orientation=”left” use_border_color=”off” border_color=”#ffffff” border_style=”solid”]

* Geophysical Survey Systems, Inc., 2015a, Radan 7 Manual.

[/et_pb_text][/et_pb_column][/et_pb_row][/et_pb_section]