Ground Penetrating Radar. Subsurface utility investigation using Ground Penetrating Radar (GPR) can be provided in locations where conventional electromagnetic pipe and cable locators are not successful, dependent on soil conditions. A typical example of this would be when non-conductive utility features require investigation (i.e., PVC water line without trace wires). Soil conditions in Williamson County are not ideal for GPR use, but it has been used successfully in certain areas to assist with utility designating.
Ground Penetrating Radar. 1. Locators shall provide or have the ability to provide G.P.R. (Ground Penetrating Radar) technology upon request. GPR can be subcontracted as long as subcontractor’s name and address is provided. A representative from the Contractor shall at all times be present when a Sub-Contractor is using or collecting data from the GPR unit.
Ground Penetrating Radar. 17.1 Ground penetrating radar (“GPR”) is a geophysical method that uses radar pulses to image subsurface objects or services, including within concrete structures. You acknowledge and agree that:
Ground Penetrating Radar. The GPR system will be used for void detection in subsurface over and around various storm structures and pipes. GPR system will scan the surface above structures to determine areas of subsurface in need of stabilization. In addition, GPR will be used for storm pipe void detection. Three passes will be made above the entire length of the pipe. A pass will be made one foot (1') to the left of the pipe, one foot (1') to the right of the pipe and a pass will be made directly over top of the pipe. The data gathered from the job site will be stored on a flash drive. A report will be generated locating and sizing any suspect void locations. Soil Stabilization Compaction (soil stabilization) with sand, cement grout mixture includes the installation of injection pipes. The location of the compaction grouting will be identified using GPR to locate area in need of soil stabilization. The responsibilities of the Contractor include project control, supervision, labor, materials and equipment to accomplish the following items of work: • Submit a detailed grouting plan to the City’s Project Manager or designee for review prior to beginning any work. • Install grout pipes. • Monitor ground and existing structure movements during grouting operations. • Perform grouting program under the supervision of personnel experienced in grouting for settlement control. • Locate and protect all utilities prior to construction or repair. Equipment used shall be specifically designed for compensation grouting. Because of the high pressure involved, all equipment, including hoses, couplings, gauges and pipes, shall be able to safely operate at the maximum grouting pressures. The mixing and grout pump system shall be designed to provide continuous flow of the grout mixture at variable flow rates and pressures without interruption during any single hookup or stage due to inadequate batching or pump feed capacity. The grout mixing system shall be capable of thoroughly mixing grout over the specified range. Grout shall either be supplied by transit mix or mixed on site. On-site mixing systems shall be capable of precisely measuring, recording, and mixing all materials. The grout pump shall include a positive displacement type pump with variable speed capabilities. The grout pump shall have the capability of injecting grout at a pressure of 240 psi. The pump shall have a minimum capacity of 10 GPM and maximum of up to 45 GPM. Pumps shall be equipped with remote controls for operation in vici...
Ground Penetrating Radar
