Friday, 17 September 2021

Everything You Need to Know About GPR and Underground Utility Locating


For underground utility locating, GPR (Ground Penetrating Radar) works as a corresponding tool to EM. Whereas the EM method is used to locate active utilities beneath the ground, GPR utility location services help locate and identify different elements that are different from their surroundings. 

Let's take a look at two of the most common yet challenging scenarios and how we can make the most out of the underground utility locating data available:

1.      Multiple Targets

In the presence of multiple buried targets such as rocks, roots, trees, etc., separating buried utilities from them can be quite challenging. Before planning any excavation, one needs to identify target responses from different depths and oriented in different directions.

2.      Weak Targets

Varied composition targets result in highly fluctuated GPR reflection responses depending upon the different soil conditions and depth.  Also, as the composition of conduit utilities and non-metallic pipes contrasts with the properties of the host material, they often create weak responses. In such instances when the response is weak, targets are usually overlooked.

Strategies That Can Help Get the Most from the Available Data


1.      MapView & Interpretation

During underground utility locating, existing records of utility maps offer initial assistance. Further, one needs to create site sketch maps based on observed targets and features. MapView allows us to see the entire surveyed area with all the analysis precisely marked on the screen.

While collecting data, the utility location services provider adds colour-coded interpretations which provides discrimination between the targets and ensures that all the targets are market.

To ensure that the entire area is properly covered, pay special attention to the direction, pattern and spacing of the ground-penetrating radar data path.

2.      Depth Slicing

When there are multiple utilities underneath the ground, depth slicing is the best tool to look for linear subsurface. It collects GPR data at varying depths and generates a 2D map image for the same. The latest GPR (ground penetrating radar) systems direct the locator through set-up, data collection, processing and exhibit depth slice. GPR with accurate GPS allows you to produce a depth slice from the line collection.

As depth slicing helps to visualise the targets and highlight utilities, it can widely help with the first challenge.

3.      Interpretation Overlaid on Depth Slices

For MapViews of user-selected utilities, depth slicing works as a complimentary. For the weak responses that aren't highlighted in a depth slice, MapView allows the utility location services provider to highlight those responses to the best of his experience and knowledge. The combination of depth slicing and MapViews has proven to be highly beneficial in complex areas.

When the target responses in the GPR cross-section are too weak to appear in a depth slice but are visible to the naked eye, it is advised to map the weak hyperbolas. This can be done by adding user selected point interpretation to the weak responses.

There is a range of varied options available to choose the interpretation colour to place on a hyperbola. 

  • Choose interpretation colour based on the colour code of utility marking
  • Choose the colour code based on the hyperbolic response strength


What's Important is to Choose One Colour Convention and Stick to it Throughout the Project?


Once the point interpretations are added, look in the MapView for the patterns made by interpretations. Some might line up, representing a linear object (mostly a utility) while some might not line up, those are point targets. Adding interpretations and overlaying them on depth slices helps identify and map utilities that do not appear on the depth slices.

Interpretations and depth slicing are the key methods to untangle complex excavation sites and identify missed utilities as a result of their weak responses. Undoubtedly, safety and damage prevention is of paramount importance for safe excavation.

To ensure accurate underground utility locating and mapping, hire professional locators and use all the tools to their best potential.

Author's Bio:

Jon Armstrong possesses immense knowledge related to GPR (Ground Penetrating Radar) and underground utility mapping. For several years, he's been associated with GeoScan Utility &Structural Investigation, renowned underground locators known for providing accurate and timely information related to underground pipe location and much more.

Wednesday, 10 June 2020

Passive vs. Active Locating Services: Which One to Choose?

Utility Locating Service

When you are planning to commence any excavation project, utility location services should be at the top of your pre-work measure list. Undoubtedly, underground utilities offer an array of advantages, but they also generate a complex maze of cables and lines that run underneath our cities.

To ensure safe excavation without risking the structure of existing utility grid, you need to hire professional underground utility locating services provider who has in-depth industry knowledge & experience to deliver accurate mapping.

There are two types of utility locating method: active locating service and passive locating service. The locator should know which method should be used and when. Let's dig further to gain a better understanding of both the methods and identify which is a better one.

1.  Active Locating Services


Active utility locating services works best when one need to locate a specific utility that runs uninterrupted, which has a continuous metallic connection from end to end. Utility location services provider sends an electromagnetic (EM) frequency on one end and transmitted down its length.

A surface receiver picks up the signal and traces it across the ground surface. Once traced and marked, the locator maps the line for your reference. With the help of this mapping, you can plan your excavation whilst avoiding that line.

Furthermore, There are Two Kinds of Active Service Locating Methods:

  • Conductive Locating – In this method, a transmitter is directly attached to the utility line which produces an EM field on the outer field.
  • Inductive Locating – It is used when there is no possibility of a direct connection. In this method, EMF is introduced to the line by placing the transmitted directly above it over the ground. 
Applications:

  • Locate a conductive or metallic utility line with an uninterrupted content from end to end.
  • Suitable for locating utilities with the presence of cathodic protection or tracing wire.
  • Rail services
 

2.  Passive Locating Services


While active utility location is a great method to acquire specific and accurate information about specific utility lines that run under a property, there are certain scenarios where it isn't effective.

For instance, when there are broken pipes, interrupted lines or non-metallic pipes (plastic/concrete), the frequency won't be transmitted across the entire length, making it difficult to fully trace it. This is where passive utility location method can help. It allows us to identify and map unknown lines as well.

One of the most popular passive utility location methods is ground penetrating radar (GPR). It allows us to map the complete surface beneath the ground which includes not only utilities but also other features which you might not be aware of, such as old wells, obstacles or voids.

Applications:

  • To locate broken utilities or where frequency can't be transmitted fully
  • For locating non-conductive lines or pipes
  • Used when access points are unknown
  • Performed at the end to ensure no utility is missed

Final Thoughts


All in all, settling on which is a better underground utility locating services method depends upon the project needs. Every method has its own advantages and disadvantages. Depending on the location of the utilities, there's also a possibility of conducting both methods in a single project itself. You might not always be aware of what type of situation is underneath – it's better to leave it in the expert's hands to find out.

Author's Bio:

Jon Armstrong is an expert of underground pipe & cable location in Geelong offering extensive experience of underground utility mapping and locating methods. Jon Armstrong is closely associated with GeoScan Utility & Structural Investigation which is a renowned underground utility locating services company in Geelong. To get a quote, you can call on 0417 309 710.

Tuesday, 28 August 2018

How to Lessen the Risk of Encountering Unexpected Underground Utilities?



Nothing can bring the development project to a standstill faster than the detection of underground utilities such as gas pipe, water pipe, electrical lines or sewer tanks. For instance, suppose, your crew identifies any utility line while digging a drain and how your entire development project will come to a halt. You might be lucky if you recognize the line before any damage is caused. But, it is not always feasible to excavate or drill holes to identify what lies underneath.

One of the best ways to locate underground utilities and other buried systems is to employ ground penetrating radar (GPR) services, which use state of the art equipment to scan the particular area and generate 2D and 3D images for evaluation. This high tech device uses high frequency radar sound waves to map out the surface underneath the ground. These services can be used for a wide range of applications and purposes including underground pipelines, underground tanks, local voids and cavities and detecting soil types.

Encountering them during on going projects can cause costly delays in the construction or property development project. For example, if we come across the underground tank and associated contamination, we will not only need to get it removed but will also need to deal with soil testing, alleviating contaminated soil and water pumping. All these resources can cause cost overruns and construction delays.

Why is GPR not Enough to Reduce the Risk of Unanticipated Underground Encounter?


Suppose you have hired a utility location services for your property which specialise in ground penetrating radar services. But during excavation, you encounter a UST which was not mentioned in their report. You might be wondering “How this can be possible?”. But, what we need to understand here is that tough GPR is a great scanning tool for detecting a large number of underground objects, it still doesn’t give you crystal clear pictures of what lies beneath your property.

Moreover, how deep you are able to see with GPR depends on the site conditions, GPR antenna frequencies and much more.


The Best Way to Overcome GPR Limitations!


With the technological advancement, there is a wide range of underground location technologies available today. By using multiple technologies such as GPR, RF (radio frequency) and electromagnetic profiling locators, you can get the thorough and detailed image of the objects lying underneath the ground.

This method can not only confirm the objects found in the earlier detection but can also help in discovering new utilities. Let’s have a look at these technologies.

  • Electromagnetic Profiling Locator: This method utilities electromagnetic waves to outline the resistivity or conductivity of the ground and offer sketches based on it. Often, these sketches narrow down the search area for the underground objects, including UST to be easily found. Later, the corresponding utilities can be found using GPR or other utility location methods. 
  • Radio Frequency (RF) Pipe and Cable Locators: This method makes use of radio frequencies that are either inducted or conducted onto cables and pipes that carry radio waves. A receiver is then used to map the produced signal. A highly experienced and professional service provider would be able to interpret good traces and set up a good locate. Here, you need to take into account that this technology is useful only for conductive materials.
Using multiple technologies along with ground penetrating rather can maximize the potential of detecting, locating and mapping every single underground object. It ultimately reduces the risk of unexpected underground encounters.

For construction and development projects, using other methods in addition to Ground Penetrating Radar can minimize the risk of encountering potential underground objects and utilities. It’s far cheaper and effective to invest in more than one utility location service than halting the projects due to unexpected encounters!



Author's Bio:
Jon Armstrong is the person with immense knowledge of the structural investigation and underground utility mapping in Geelong. He works with GeoScan, the leading provider of underground utility mapping and locating services in Geelong. Call us on 0417 309 710.

Friday, 10 February 2017

5 Misconceptions about Ground Penetrating Radar for Utility and Ground Investigation



If you need to drill into the ground for any kind of structural activity that you wish to do underground, it is important that you are aware of what is beneath the level surface. There may be wires, pipelines, and cables which may get damaged due to unplanned or reckless drilling. This can pose not only legal and procedural hassles for you, but may be a danger to society as well as for the technicians involved.

To avoid this, there is equipment called Ground Penetrating Radar used by GPR technicians for locating underground utilities like pipes and cables. However, there are some misconceptions that people attach to the use of GPR. Let’s bust these myths.


Misconception # 1


X-Ray Equipment Do A Better Job.



X-ray equipment is no longer the preferred method for mapping utilities, especially for pipe locating.

Due to the top-only images that they give, X-ray machines have been replaced by Ground Penetrating Radars as the preferred equipment for mapping the underground utilities. Ground Penetrating Radars can provide a much more complete, comprehensive, and three-dimensional view of the network below the surface.

Misconception # 2


A Look at the Maps and Blueprints Drawn Earlier and Available with the Utility Companies can Help You to Zone into the Underground Pipelines and Other Utilities.

Nothing can be more primitive than. You never know, things might have changed after the maps are drawn out. With old drawn maps and blueprints, there is no way of being sure that what lies beneath the ground is exactly according to the maps. Ignoring this fact is a big risk.

Relying on older maps and blueprints is certainly not the right way to choose for pre-planning of utility and ground investigation. Ground Penetrating Radar services provide the best and most accurate method for mapping underground utilities, especially for locating pipes.

Misconception # 3


There is Nothing better Than Drilling Down and Seeing What Lies Beneath with Your Naked Eyes.

A very dangerous and risky proposition. This defeats the very purpose and base of the ground penetrating exercise. The entire exercise of locating the underground network of pipes and cables is to eliminate chances of damage to the pipes, pipelines, or cable wires. By drilling, you never know when you might inadvertently hit a pipeline triggering a major damage in the utilities.


Misconception # 4


Ground Penetrating Radar Services Benefit Only Those Searching For Underground Pipelines

There are numerous ways in which you can utilize Ground Penetrating Radar services. You'll be surprised to know that even if you want to dig a water-well in your premises, you can take the help of these services. Archaeologists, environmental scientists, geologists can utilize these services in their own fields of activity. A geologist or, in particular, a seismologist can make use of these for locating a landfill or a crusty area beneath the surface when studying earthquake-prone zones.


Misconception # 5


Buy the Equipment. It's Easier and Cheaper To Do It Yourself Than to Hire Someone To Do It.

This only makes sense, if you are going to use the equipment on a daily basis and extensively. Otherwise, the hundreds of dollars that you may spend on it may never give you any proper return on investment. Moreover, using specialized GPR technicians to handle the equipment means that you are getting the correct and accurate readings.

Get yourself a specialized Ground Penetrating Radar services company which can give you an accurate map and work efficiently ensuring required levels of safety.



Author Bio
Jon Armstrong is a specialist. Being a part of Geoscan : Utility and Structural Investigation, he has immense proficiency and expertise as a GPR technician. Geoscan has been providing these services in Melbourne and Geelong and has secured a highly acclaimed position for itself. Geoscan is accredited with most bodies in this field and is a reputed name in structural ground investigations.

Saturday, 6 June 2015

Get Reliable Underground Cable Locating Services



In a country like Australia, you will always find some or the other construction activity. This may be in terms of new establishments, or repair work for existing ones. However, one fact that always goes unnoticed is the huge, wide and complex network of underground utilities. Being underground, these utilities may not catch your attention immediately; however, their importance cannot be overlooked due to various reasons.

Presence of risk


The wide network of utilities comprises of electricity cables, sewers, water pipes and gas pipes. All these utilities can pose significant danger if they are damaged due to any reason. This damage may pose risk to workers on construction sites. Additionally, if not addressed, these damages may lead to grave effects.

Cable locating services to the rescue


Presence of utility networks is found everywhere as mentioned earlier and it spreads across residential as well as commercial regions. All this makes it imperative that when construction activities are carried on, these cables or pipes based underground are located first to avoid issues later on.

In Geelong region, there are many services that offer facilities to locate underground utilities. These cable location Geelong companies are adept at finding the exact location of these utilities and also find faults if any.

Moreover, the Cable fault finding Geelong services ensure that people working at construction sites are not exposed to unforeseen dangers that may arise due to faulty nature of underground cables. They find relevant information about these hidden pipes and cables before the work of excavation or other construction activities begins.

Based on these findings, the construction employees then plan their work; thus ensuring safety of everyone and everything involved. Construction people need to plan their work based on the findings of reliable and reputed cable locating services as they are in a better position to accurately determine position of pipes and cables below the surface.

Reputed utility locating services use latest equipment that is able to find faults in underground cables. Moreover, with latest tools, the work can be carried out quickly; thus ensuring that time is saved and construction activity is not delayed.

The right source


GeoScan is one of the well-known and reputed cable location service that can act as a perfect source for all your needs related to finding faulty cables underground. The company has a reputation of accurately determining presence of underground utilities.

With a strong and efficient work force to back it up, GeoScan has already served many satisfied clients across Australia. Most importantly, GeoScan provides round the clock support; thus ensuring that your needs related to cable fault finding in Geelong do not face any hurdles at any given time. You can completely rely on us to provide quality work.

Wednesday, 3 December 2014

Understanding of Concrete Inspection of Building


Technological innovation is a ceaseless processes that revolutionize automation regularly. Unlike the old times, work that involves concrete has become safe, easy, effective and brisk. Further, finding any obstructions in such work has also become trouble free. This process of finding obstructions in concrete that might be hidden in it is termed as concrete scanning or imaging.

GeoScan being an accredited company which specializes in building inspection work that includes geophysical and structural investigation along with underground utility, has the necessary acumen about concrete scanning in Melbourne. Additionally, GeoScan also conducts concrete building inspections in Geelong.

Why is concrete scanning needed?


Concrete scanning has numerous benefits and is used during the construction and design phase of projects. The use of this technology enables to locate conduits, tension cables, voids, slab thickness measure and rebar; thus helping to map the concrete structure for any reference in future.

Workers engaged in digging work were exposed to environments where things embedded below the surface were not known. This posed dangerous situations and also wasted lot of time. With concrete scanning, things have become easier and safer for workers.

The system enables to accurately identify objects and locate depth below concrete structures up to 300mm-500mm approximate. The process negates guessing work and provides contractors and engineers the liberty of obtaining precise information which alleviates change orders and unnecessary costs.


How GeoScan can be a best choice?


GeoScan, as mentioned earlier, has extensive experience and expertise in building inspections. Our team is qualified for finding correct defects and discovering minutest of faults which if not found can cause large scale damages. This experience has helped us garner some reputed establishments as our clients across Melbourne & Geelong. We boast of round the clock service and high standards with regards to customer service. Clear understanding and use of high-quality equipment, enables us to provide unequaled results.



Wednesday, 22 October 2014

Top Concrete Scanning Company in Geelong



Concrete scanning in Geelong is essentially undertaken for projects that involve cutting, coring or drilling into concrete structure. It aims to identify safer areas for these projects so that no object can hinder their progress.

Among many types of concrete scanning in Melbourne, some include footpath scanning for cable location, slab, wall, beam scanning.

Applications that are used for concrete scanning in Geelong by professional companies such as GeoScan are:

  • Structural Steel (Rebar and Ligature Identification)
  • Post Tension cables (PT'S)
  • Pipes and Conduits (Services in Structures)
  • Live Electrical Wiring present in Structures
  • Heating Lines (Concrete Slab Heating)
  • Concrete assessment and structural investigation, such as looking for voids and structural deterioration

Concrete scanning is also undertaken as part of building inspection. Building inspection can be either pre-construction, post-construction or during the construction exercise. The main objective is to locate any harmful objects in the construction of building. Concrete scanning in building inspection exercise involve:

  • Concrete floor scanning
  • Concrete wall scanning
  • Concrete ceiling scanning
  • Concrete slab scanning
  • Concrete beam scanning
  • Roof space scanning
  • Building exterior scanning
  • Building interior scanning

In Melbourne, and Geelong when a company sets out to launch any new project, main purpose of concrete scanning is to accurately locate structures or objects in concrete.

This technique has been popular across the globe because it is a non-destructive (NDT) which consequently saves time and energy compared to its previous counterparts. This then results into its cost-effectiveness as it does not involved traditional processes like hitting or cutting through live electrical wires, post tension cables, or any sort of service in the structure frame work. This also eliminates intense noise pollution and inconvenience to the surrounding area.

For the successful concrete scanning, it is very important that your service provider of concrete scanning in Geelong has the latest equipments. One of your reasons why GeoScan should be your choice as concrete scanning provider in Melbourne is that we use latest equipments to undertake concrete scanning. We use:

  • Latest ground penetrating radar application
  • High frequency 1.6 MHz and 2.3 MHz Antennas
  • Antennas with a depth penetration range of 300mm-400mm

Apart from having latest equipments, we also have fully trained and professional experts who are available 24*7 for any of your needs. We also provide emergency services with regards to concrete scanning in Melbourne.