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Why Are There So Many Kinds of CPT Rigs?

As you look through our website, you'll see that there are a number of different types of CPT Rigs. As you can imagine, they each have their purpose, or 'application'. In order to understand why different types of CPT Rigs exist, it's helpful to remember how CPT works in the first place. Cone Penetration Testing The goal of Cone Penetration Testing is to drive a hardened cone vertically into the the ground and to keep it moving at a specific rate of progress. The force that it takes to maintain the cone moving downward at a defined rate is an indicator of how hard the soil is at a given depth. The friction the cone sleeve encounters along the way gives us an indication of the make up of the soil. Deciding Between CPT Rigs As you can imagine, as the cone progresses further downward and encounters different types of soils, sands, clays and rocks it can take a substantial amount of pressure to keep it moving! One of the first factors that influences the design of CPT Rigs is the maximum amount of pressure that will be required to perform a specific test, to a specific depth in a given geological area. As much as 20 tons of downward force may be required to perform a broad enough range of tests to make a given rig viable for a market. For every ton of downward pressure on the test cone through the rod system, you have to have a reaction force equal to this to keep the Rig from lifting up. This means that either the Rig has to be heavier than the maximum push force, plus a safety margin, or it needs to be anchored down in some way as to reliably resist the upward force generated by [...]

By smadi66|December 5th, 2019|Geotechnical Connecticut, Geotechnical Florida, Geotechnical Iowa, Geotechnical Kansas, Introductory, Cone Penetration, Geotechnical Colorado, Geotechnical Delaware, Geotechnical Indiana, Geotechnical Idaho, Geotechnical Illinois, Geotechnical Georgia|0 Comments

LED Fluorescence Detectors and Fuel Fluorescence Detection (FFD)

Hydrocarbons: including gasoline, kerosene, diesel fuel, jet fuel, lubricating and hydraulic oils, and tars and asphalts contain Polycyclic Aromatic Hydrocarbons (PAH’s). Polycyclic Aromatic Hydrocarbons (PAH’s) distributed in soils and groundwater fluoresce when irradiated by ultraviolet light. Because different types of PAHs fluoresce at different wavelengths, each has its own fluorescence signature. Using an instrument that measures the intensity and wavelength of the fluoresced hydrocarbon enables the assessment of the hydrocarbons present. This makes UV Fluorescence a useful technology to use in characterizing surface, subsurface and groundwater hydrocarbon contamination. We call this Fuel Fluorescence Detection (FFD). What's the right fluorescence detector for you? Using handheld UV lights enables site technicians to establish the nature and distribution of contamination above ground. For surface spills such as what gathers along a shoreline or for surface based operations such as above ground tanks and pipes, this can be a useful place to start. For underground storage tanks a useful way to begin site characterization is with a subsurface probe. Engineers trying to establish the limits of the ‘plume’ or the depth of the contaminant as it travels underground. Plumes will extend outward, downward and upward depending upon factors such as the flow of groundwater and the confining layers of clay and rock. Leveraging the ability to generate and measure fluorescence underground requires a step up in technology. In the case of CPT, a UV light source is placed in the cone itself. Fiber-optic cables transmit the resulting fluorescence to the surface where the intensity and wavelength can be measured. Because of the efficiency of CPT, large and complex sites can be characterized quickly and efficiently. The data logs are available immediately to influence critical decision-making which can help to manage costs in the long term. For instance monitoring wells may need to be installed [...]

By smadi66|December 5th, 2019|Introductory, Soil Testing, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical California, Geotechnical Colorado, Geotechnical Washington, Geotechnical Wisconsin, Geotechnical Wyoming, Geotechnical Alabama, Geotechnical Connecticut, Geotechnical West Virginia|0 Comments

Ensuring That Your CPT Data is Correctly Reported and Interpreted

It is important to understand when interpreting CPT data the physics of how the data is produced. This will lead to a better appreciation of where CPT data should be validated with other types of tests in order to ensure that it is being correctly reported and interpreted. In CPT (Cone Penetration Testing), when the tip of the cone is being advanced, there is pressure exerted on the tip itself. This pressure is created from the resistance to downward force by whatever soil is resisting on the cone tip. However, this pressure is not simply exerted from the ground immediately in front of the tip. Rather, the cone forces the ground immediately in front of it to compress. This compression forces the ground in front of it to 'fail' that is, the soil cohesion is not sufficient to resist the tip load, and the soil compresses further down or moves out of the way down, sideways or a little bit away from the cone itself, upwards. Because of this movement and compression, the pressure exerted back on the cone tip is generated from a large area of soil below, around and a bit behind the cone tip itself. This means depending on soil stratification that the instruments in the tip sense soil resistance from around 5 or more cone diameters ahead and around the tip of the cone. Using a cone of 1.5 inches in diameter means that you are actually taking an average cone resistance measurement. This is sometimes called a 'tip influence zone'. If you are pushing through a sub-surface feature, such as a landslide slip face or a layer of softer clay that is a foot or less, it is quite possible to miss this feature entirely. In engineering speak, you might read something like 'exercise caution [...]

By smadi66|December 5th, 2019|Experienced, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical California, Geotechnical Colorado, Geotechnical Wisconsin, Geotechnical Delaware, Geotechnical Alabama, Geotechnical Wyoming, Geotechnical Connecticut, Geotechnical West Virginia, Cone Penetration, Soil Testing|0 Comments

Testing Pavement Sections at Ohio University

Ohio Unversity Accelerated Pavement Tester in Action! In 1997 Vertek delivered our first of many Accelerated Transportation Loading Systems (ATLaS). Ohio University published this video, dated in 2012 of the pavement load tester in use at their Accelerated Pavement Load Facility. Common pavement tests include: Pavement coating lifetime analysis Experimental pavement fatigue estimation Pavement rutting Impact of temperature cycling on pavement Effects of wheel wander on pavement lifespan [/fusion_youtube] Though our designs have evolved since 1997 to better handle environmental and energy useage factors, many components of the above are still present on our current deliveries of pavement and bridge deck testers. These testers are designed to deliver actionable data regarding the lifespan and limits of road surfaces and pavement composition in shortened timespans. While this website is primary dedicated to our CPT business, Vertek's wealth of geotechnical manufacturing experience has led to additional focus on structural integrity fields such as load testing. See our ATLaS pavement and bridge load testing page for more information or to inquire.

By smadi66|December 5th, 2019|Geotechnical Arkansas, Geotechnical California, Geotechnical Colorado, Geotechnical Ohio, Geotechnical Delaware, Geotechnical Georgia, Geotechnical Alabama, Geotechnical Connecticut, Geotechnical Florida, Vertek Partners, Video Posts, Geotechnical Arizona|0 Comments

CPT Rigs: Types, Uses & Applications

If you're familiar with the CPT University then you may have had the chance to see our article: Why Are There So Many Kinds of CPT Rigs? As you may have read, there are many different rigs available; but depending upon the types of surface conditions or the terrain, one option may be more suitable for your project over another. Read on to take a deeper dive into a few different examples of CPT rigs, uses and applications. S4 CPT Push System The S4 is a robust and affordable push system that can be attached to many types of heavy equipment including ski steers, trailers, backhoes, and more. The S4 is revolutionary in many respects, for instance it provides 20 tons of CPT push capacity in a compact and affordable package. This agile, lightweight rig is only available from Vertek CPT and is one of the most inexpensive alternatives to the traditional rig. The system is equipped with full-systtem hydraulics giving you full operating control, as well as the ability to drive 2 Motorized Anchor Heads and all of the CPT system features you need to eliminate the need for external cylinders. There is no alternative to the S4 Push System that lets you enter the CPT business with confidence that you can prove out your business model before going 'all in'. CPT Track Rigs With fully equipped features and capabilities, CPT Track Rigs are available in light, medium and heavy configurations. These CPT rigs are designed to meet rigorous requirements and the demanding range of foundation work you are likely to encounter as your business grows. For certain geographical areas soft soils, boggy areas and changing environments demand a track rig. This means that you can immediately differentiate your services from the competition. CPT Track Rigs are super-pro. Track [...]

By smadi66|December 4th, 2019|Geotechnical Colorado, Geotechnical Delaware, Geotechnical Idaho, Geotechnical Illinois, Geotechnical Georgia, Geotechnical Connecticut, Geotechnical Florida, Introductory, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical California|0 Comments

Terracon Consulting Engineers Takes Delivery of 20 Ton CPT Track Rig

Cone penetration test rig leaves Vertek CPT's Randolph, VT facility. It can be a bit somber watching one of our CPT track rigs head out the door after spending a few months building the rig here in Vermont, but thankfully we get to work with our partners long after the sale to make sure they're successful in the field. This 20 ton cone pentration test track rig is headed to Terracon Consulting Engineers and Scientists of Olathe, Kansas. [/fusion_youtube]

By smadi66|December 4th, 2019|Geotechnical Colorado, Geotechnical Delaware, Geotechnical Indiana, Geotechnical Idaho, Geotechnical Illinois, Geotechnical Georgia, Geotechnical Connecticut, Geotechnical Florida, Geotechnical Iowa, Vertek Partners, Video Posts, Geotechnical California|0 Comments

Towable CPT Trailer – Push System on Wheels!

New - Mount an S4 CPT Push System on equipment or a trailer! Customer response to our new S4 Push System has been very impressive. The most affordable and flexible 20 ton push system available has made CPT newly accessible to a variety of service providers around the world without the need for large dedicated vehicles. In keeping with our history of cone penetration innovation we'd proud to show off our latest improvement to the S4 Push System: Towability. That's right, the S4 can now be purchased attached to our custom trailer enabling it to be driven from job site to job site behind any full size pick-up truck. [/fusion_youtube]

By smadi66|December 3rd, 2019|Geotechnical Kentucky, Geotechnical Idaho, Geotechnical Illinois, Geotechnical Georgia, Geotechnical Connecticut, Geotechnical Florida, Geotechnical Iowa, Geotechnical Kansas, Introductory, Cone Penetration, Video Posts, Geotechnical Indiana, Geotechnical Delaware|0 Comments

Ensure Properties are Accurate Using Sediment Cone Testing

Obtaining a representative and undisturbed sample of cohesive sedimentary soil, such as sand, is very difficult and often times impossible. Because of this, determining the properties of sandy or fine grained soils is best done in-situ, making Cone Penetration Testing (CPT) one of the best testing methods for measuring mechanical properties of sediment. Sediment Cone Testing When conducting cone testing of sediment the horizontal stress and sediment density are the most influential parameters on the cone tip resistance. The cone penetration tip resistance is influenced by the soil properties ahead and below the tip. If you're dealing with a sand layer that is less than 70 cm., it's important to consider what types of stratification it is located between. For example, if it's located between deposits of soft clay the CPT may not reach it's full value within the sand layer, meaning the relative density of the sand may be underestimated. By monitoring the CPT pore pressures, these influencers can be identified. The substantial effects of soil compressibility on CPT measurements are considered to be an advantage if they are identified correctly. Compressibility is one of the key factors to successfully determining soil properties and classifying soil types. Using CPT, relative density and friction measurements soils can be broken up into high, medium and low compressibility. By classifying sediment compressibility during cone testing you can better measure the particular sediment properties. Sand for example, originates from quartz or silica; it contains hard materials, does not have cleavage planes and is resistant to weathering. Certain sands, for example siliceous sand, contain trace portions of other minerals, like chlorite. Compared to other types of soil, the compressibility of sand is most complicated because it is dependent on several different factors, including: grain size and shape, particle crush-ability, angularity, grain mineralogy, void ratio, [...]

By smadi66|December 3rd, 2019|Geotechnical Alabama, Geotechnical Connecticut, Geotechnical West Virginia, Experienced, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical California, Geotechnical Colorado, Geotechnical Delaware, Geotechnical Wyoming, Geotechnical Wisconsin|0 Comments

When Should You Consider SPT Testing Over CPT?

If you’ve been following the CPT University, you likely already know that Cone Penetration Testing isn’t the only method of testing soil. Mud rotary drilling, for example, has come up in the past along with one of the best known soil testing procedures out there: the Standard Penetration Test (SPT). Like Cone Penetration Testing, SPT Testing is widely used. But can it outperform CPT Testing? Read on to find out. What is SPT Testing? SPT Testing uses a thick sample tube to determine the relative density of granular deposits, typically sand and gravel. The sample tube is placed at the bottom of a borehole and struck with a heavy slide hammer repeatedly. The number of hammer strikes is important; the test operator must track how many strikes it takes to drive the sample tube 6 inches into the soil. The test is completed when the sample tube reaches 18 inches deep. As you might imagine, a test that requires only a sample tube and a hammer offers a few notable benefits, namely that it is simple and inexpensive to perform. It is also the best solution for testing soil in areas that are difficult to access with vehicles. In other words, if you need to perform a soil test quickly, easily and at minimal cost, SPT Testing is hard to beat. SPT Testing does have its drawbacks, though. Most notably, it’s inaccurate compared to more advanced methods, especially when sampling coarse sands or clay. As such, it’s rare to encounter a scenario in which SPT Testing is preferable to Cone Penetration Testing. Not only is CPT far more accurate than the standard penetration test, it also manages to be relatively inexpensive compared to other testing methods. CPT is also a fast, safe and versatile option. Sure, it can’t match the [...]

By smadi66|December 3rd, 2019|Geotechnical Connecticut, Geotechnical Florida, Introductory, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical California, Geotechnical Colorado, Geotechnical Delaware, Geotechnical Wyoming, Geotechnical Georgia, Geotechnical Alabama|0 Comments

10 Essentials of Construction Testing and Engineering

Testing construction material is an important step in the building process, as the outcome of testing, as well as the processes used, will ultimately affect the safety and longevity of the final building site. While the reality on most building sites is that the accuracy of testing and cost effectiveness are often balanced, these days it's pretty easy to ensure a high degree of accuracy while still keeping costs at a minimum. Regardless, the overall goal is to establish the foundation for assisting design engineers in making good, informed decisions while meeting building code requirements. By testing construction materials, along with ensuring proper geotechnical analysis, it's possible to guarantee buildings will meet regulatory requirements and last over time. Overall, construction materials, engineering and testing (CoMET) are used to ensure quality control and construction quality assurance. However, construction testing and engineering can only go so far without some key essentials. 10 Essentials of Construction Testing and Engineering: Observation, testing and evaluation of building materials Observation, testing and evaluation of quality construction methods and processes Observation, testing and evaluation of building outcomes Meeting building code compliance Site grading and subsurface prep Soil testing and analysis; evaluation of subsurface materials Cost-effective geotechnical sliutions and materials used Safe application of contaminated subsurface materials Proper recycling of excavated materials and debris Assurance of ground stability, especially in areas common to environmental disaster such as earthquakes, flooding, etc. By making sure to follow each of these 10 essential steps, you're ensuring that every aspect of inspection is covered, in turn ensuring a stable, up-to-code building for the long run. That said, there are a couple more important points to note: CoMET services must be performed during the early stages of a project and processes must be hands-on to ensure each step is given complete attention. Getting [...]

By smadi66|December 3rd, 2019|Geotechnical Connecticut, Geotechnical Florida, Introductory, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical California, Geotechnical Colorado, Geotechnical Delaware, Geotechnical Idaho, Geotechnical Illinois, Geotechnical Georgia|0 Comments