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We locate assets and also provide service for concrete slab scanning on industrial estates, Public Roads and reserves, Private Property just about anywhere you need to dig, trench or excavate!
• The latest Mala GPR units are used various antennae units are available depending on soil types
• Real time imaging and marking is available on site
• Detailed data processing off site if required and information can be laid up onto existing survey drawings
• Now Implementing the Mirror System from Mala using a 16 channel system for true 3D digital mapping at speeds up to 15klph for further information on this first truly 3D scanning please refer to the Mala web link below
Case Study
Description of the job.
The section of the road in Sydney's north was surveyed using the Mala MIRA system. The objective of the project was the location and mapping all underground assets and services ewithin the survey area.
When mapping areas where targets are of unknown size, shape and orientation it can be difficult to gather data dense enough to get a good pictures picture of what's hdden underneath. Precise positioning is also a common problem. This case study shows an effective method for mapping large areas, with line sapcing small enough to prevent information loss and with a system that lend itself to precise positioning of each profile. This method of data collection and precise positioning is not available using standard, off-the-shelf equipment. this case study is an example of state of the art technology for detailed subsurface investigations.
Equipment Used
The equipment consisted of a 400MHz,16 channel antenna array, towed behind a car, a Mala array control unit, a total station, a prism for tracking the array position and a laptop for data collection. Data processing and interpretation were done using rSlicer software, package especially developed for interpretation of real 3D data.
Investigation method
The antenna array was towed behind the car in an "up the road, down the road" fashion. The array unit has spray paint bottles attatched at both corners of the system in order for the driver to mark the actual path and ensure full coverage of the area. Positioning was recorded at all times using the total station and prism.
Results
In Figure 1 a top view, at 18cm depth, is shown. The yellow lines show the survey paths. already from a first glance at one depth, an underground assset is clearly visible in the ground. Data is processed using a number of different filters to remove unwanted background noise and to create a clearer picture. Identified assets are marked at their depths and labelled. This information can be exported as ASCII and .dxf formats which can be used in AutoCAD and similar programs.
Discussion
The survey covered 200m long stretch of road and took effectively 3 hours, including mobilisation. The post processing took about 3 hours.
Obviously the Mala MIRA array approach is more expensive, due to the equipment cost, than a traditional, single antenna, approach. But this is somewhat imaginary since a survey with single antenna with the same data density would be practically impossible, and if carried out, actually more expensive. Given the details and reliability in the final interpretations/data, it should be clear that array surveys have the potential of being an efficient and fast method for this kind of investigation where the demands for the detailed results are high.
http://www.malagpr.com.au
Locating | Utility Detection | Utility Mapping
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