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Attending CPT Symposium 2014 Las Vegas, Nevada

See The Vertek S4 Push System in Person! The 3rd International Symposium on Cone Penetration Testing will be held at the Mandarin Oriental hotel in Las Vegas, Nevada, May 12-14, 2014. The theme of the Symposium is the solution of geotechnical and geo-environmental problems using the Cone Penetration Test (CPT). We'll be at booth #1 and also setup outside with our new S4 Push System which is designed to be attached to a wide variety of equipment. Learn more about our entire line of products and data acquisition systems.

By smadi66|December 5th, 2019|Geotechnical Washington, Introductory, Vertek Partners, Geotechnical Nevada, Geotechnical Rhode Island, Geotechnical South Carolina, Geotechnical South Dakota, Geotechnical Texas, Geotechnical Utah, Geotechnical Vermont, Geotechnical Virginia, Geotechnical Tennessee|0 Comments

CPT Case Study: GEI Consultants

30 years of Cone Penetration Testing with GEI We're proud of the relationship we have with our long time customers. We succeed together. One of these groups is GEI Consultants, which has been delivering engineering services around the globe since 1970. Sean Brady, Senior Instrumentation Specialist with GEI, provided CPT University with background on their operation as it pertains to their CPT efforts. Briefly describe GEI’s engineering focus. What do you do for whom? GEI is a medium size engineering firm with around 700 employees in the United States. Our business line within GEI is Geo-technical, non-destructive testing, and geophysics. Our engineering’s have designed over 75% of downtown Chicago’s foundations and most of the tallest buildings in the world. We often are part of the design team when difficult and challenging soils are encountered. We perform CPT’s on earthen dams/embankments, river sediment depths, USCOE projects from Ft. Peck Montana to New York, RR alignments, bridge embankments, and Power plants. A little of everything you can imagine from Water, RR bridges, Landfills, stability of tail basins for the mines. We also oversee other companies performing CPT. We just worked in Asantana, Kazahkstan overseeing a new energy exposition 2016 project for both SPT’s and CPT. Also have overseen CPT testing in Doha, Qatar. When did CPT first become of interest and why? We have over 30 years of CPT testing experience. In the late 80’s we purchased a 30T CPT truck and traveled around the US performing CPT on challenging geo-technical projects. In the mid-90’s we sold our truck and started to perform CPT testing behind drill rigs. At the time we had a fleet of 18 drill rigs from track mounted, ATV, truck mounted, Barge mounted, etc. We get involved with delicate soils all the time. In some cases even when [...]

By smadi66|December 4th, 2019|Geotechnical Wisconsin, Geotechnical Alabama, Geotechnical West Virginia, Vertek Partners, Geotechnical Texas, Geotechnical Utah, Geotechnical Vermont, Geotechnical Virginia, Geotechnical Washington, Geotechnical Wyoming, Geotechnical Tennessee|0 Comments

Cone Penetrometer Testing via Speed Lock Rods

The strongest direct push rods in cone penetration testing. Unsurpassed Joint Strength Vertek manufactures a full line of CPT push rods with our proprietary Speed Lock dual-lead thread design. Speed Lock Rods provide unsurpassed joint strength, up to 50% stronger than industry standard V-threads. Our unique rope thread design uses less of the available wall thickness and balances the strength between the male and female thread ends. Speed Lock coupled joint achieves nearly 90% of the strength of the heat treated rod stock. Increase Speed, Reduce Operator Fatigue Our dual-lead thread provides fast coupling; 2.5 turns to couple or uncouple compared with 5-7 turns for competitor’s rods improving worksite productivity. Flexibility and Adaptability to Variety of Cones Speed Lock Rods are available in standard 1.44” and 1.75” diameters. Custom sizes include 2”, 2.25” and 2.5”. Vertek also manufactures custom adapters to permit use of our advanced thread design with your current inventory of CPT equipment. Make the most of your CPT rig and cone penetrometer testing equipment with Vertek Speed Lock Rods!

By smadi66|December 4th, 2019|Geotechnical Alabama, Geotechnical West Virginia, Experienced, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical Utah, Geotechnical Vermont, Geotechnical Virginia, Geotechnical Washington, Geotechnical Wyoming, Geotechnical Wisconsin|0 Comments

The Application of Dynamic Cone Penetration Testing (DCPT)

Assessing the level of compaction of sub-surface soils can be essential to designing and building structures, particularly those subject to transient or cycling loads. A perfect example is roadways. If the soil beneath a roadway is not compacted sufficiently, then over time the cycling loads of passing traffic will compact the soil further, leading to surface failure such as large cracks, potholes and displaced pavement. Assessing the compaction of non-cohesive soils such as fine sands is a difficult challenge. As we've noted in other blog posts, removing a sample from the ground and sending it to a lab is not only time consuming and expensive, but can be highly inaccurate in non-cohesive soils because the samples by necessity are disturbed from their sub-surface condition. The Dynamic Cone Penetrometer Test (DCPT) is one of many forms of in-situ soil characteristic tests that are designed to assess soil density. It shares some characteristics of both SPT and CPT testing, which enables it to provide a useful and in the right application can deliver a complementary data set and is less expensive and troublesome than Nuclear Density testing. The Standard Penetration Test (SPT) is done by using a sample tube which has thick walls to prevent deformation during the test. To conduct a test, a borehole is drilled to a specified depth. The sample tube is driven into the bottom of the borehole using a drop hammer of a defined weight dropped a defined distance. The number of blows (N) needed to drive the sample tube 6, 12 and 18 inches is recorded. The SPT provides a rough indication of the soil density at depth. As noted in previous posts (link here), getting accurate data for soil density can be a complex challenge. SPT provides an estimate but is not as accurate as [...]

By smadi66|December 3rd, 2019|Geotechnical West Virginia, Soil Testing, Geotechnical Arizona, Geotechnical Arkansas, Geotechnical California, Geotechnical Colorado, Geotechnical Virginia, Geotechnical Washington, Geotechnical Wyoming, Geotechnical Wisconsin, Geotechnical Alabama|0 Comments

CPT Testing, Part 1: Introduction to the Basic Concepts

If you have ever been curious about the Cone Penetration Testing (CPT) business, you have come to the right place. In today's post we are going to take a dive into the basic concepts and what expanding into CPT can do for your engineering business. Geotechnical Engineers and CPT Testing Geotechnical engineering is a branch of civil engineering that focuses on the engineering behavior of earth materials. Geotechnical engineers have been using Cone Penetration Testing (CPT) for over 40 years to assist in the design and construction of foundations, embankments and other structures. The standardized CPT works by pushing a 55-60 degree cone into the ground at a rate of 1-2 cm per second and is used to identify the conditions in the upper 100 feet of the subsurface. The data compiled from this testing is valuable for assessing the subsurface stratigraphy associated with soft materials, discontinuous lenses, organic materials, potentially liquified materials (such as sand, silt and granule gravel), and predicting landslides or ground settling. The cone resistance in conjunction with the friction ratio can also be used to determine soil types. While these results are often more accurate when referring to textbook soils, there are some major benefits to utilizing CPT techniques as opposed to drilling. In fact, there are a number of different advantages of CPT, including: economically friendly testing, as well as its ability to perform at a fast rate and effective in characterizing large volumes of soil without having to do a large number of laboratory testing. CPT is also accurate, eliminating the possibility of disturbances to soil samples and sample storage. By leveraging CPT results, engineers can determine the best methods for several aspects of design and construction projects. Detect lenses, thin layers and sand stringers. Evaluate the thickness and extent of compressible soil [...]

By smadi66|December 3rd, 2019|Introductory, Geotechnical Rhode Island, Geotechnical South Carolina, Geotechnical South Dakota, Geotechnical Texas, Geotechnical Utah, Geotechnical Vermont, Geotechnical Virginia, Geotechnical Washington, Geotechnical Tennessee, Geotechnical Pennsylvania|0 Comments

What to Consider Before Buying a Used CPT Rig

When faced with the prospect of a major purchase, it’s common to look into the possibility of buying used. In most circumstances, this is a perfectly valid option with a number of upsides, the most obvious of which being a lower upfront investment. However, when it comes to buying a used CPT Rig, you might be better off buying a new rig from a trusted vendor. Here’s why. Used Means Used First and foremost, Cone Penetration Testing is too important to leave up to chance. Sure, your used CPT Rig may appear in fine working order and you may have acquired it from a reputable seller, but there’s no getting around the simple fact that a used rig has a higher chance of failing than a brand new one. This point is further compounded when you consider the fact that even the best used CPT Rig dealer can’t match the expertise of a CPT Rig manufacturer. Expertise Straight from the Source When you buy a CPT Rig from Vertek CPT, you’re also getting access to our knowledgeable technical sales staff; something used CPT Rig sellers can’t offer. Additionally, in some instances, Vertek CPT will provide comprehensive training and will even accompany you to your first job site to maximize your chances of success. You can’t get that kind of service or expertise from a used CPT Rig dealer. Even if you think you have enough experience with CPT Rigs to ensure success with a used rig, though, it’s also worth noting that not every CPT Rig is right for every task. A Wide Variety of CPT Rigs If you have a broad enough knowledge base to feel comfortable buying and setting up a used CPT Rig, then you probably also know that there are many kinds of CPT Rigs. Cone [...]

By smadi66|December 3rd, 2019|Geotechnical West Virginia, Introductory, Geotechnical South Carolina, Geotechnical South Dakota, Geotechnical Texas, Geotechnical Utah, Geotechnical Vermont, Geotechnical Virginia, Geotechnical Washington, Geotechnical Tennessee, Geotechnical Wisconsin|0 Comments

Cone Penetration Testing Glossary of Terms

This brief glossary contains some of the most frequently used terms related to CPT/CPTU. These are presented in alphabetical order. CPT: Cone Prenetration Test or the act of Cone Penetration Testing. CPTU: Cone Penetration Test with pore water pressure measurement - a piezocone test. Cone: The part of the Cone penetrometer on which the end bearing is developed. Cone penetrometer: The assembly containing the cone, friction sleeve, any other sensors and measuring systems, as well as the connections to the push rods. Cone resistance: The total force acting on the cone, divided by the projected area of the cone. Corrected cone resistance: The cone resistance corrected for pore water pressure effects. Corrected sleeve friction: The sleeve friction corrected for pore water pressure effects on the ends of the friction sleeve. Data acquisition system: The system used to measure and record the measurements made by the cone penetrometer. Dissipation test: A test when the decay of the pore water pressure is monitored during a pause in penetration. Filter element: The porous element inserted into the cone penetrometer to allow transmission of the pore water pressure to the pore pressure sensor, while maintaining the correct profile of the cone penetrometer. Friction ratio: The ratio, expressed as a percentage, of the sleeve friction, to the cone resistance, both measured at the same depth. Friction reducer: A local enlargement on the push-rod surface, placed at a distance above the cone penetrometer, and provided to reduce the friction on the push rods. Friction sleeve: The section of the cone penetrometer upon which the sleeve friction is measured. Normalized cone resistance: The cone resistance expressed in a non dimensional form and taking account of stress changes in situ. Net cone resistance: The corrected cone resistance minus the vertical total stress. Net pore pressure: The meausured pore [...]

By smadi66|December 3rd, 2019|Introductory, Cone Penetration, Geotechnical Texas, Geotechnical Utah, Geotechnical Vermont, Geotechnical Virginia, Geotechnical Washington, Geotechnical Tennessee, Geotechnical Wyoming, Geotechnical Wisconsin, Geotechnical Alabama, Geotechnical West Virginia|0 Comments

What Can You Reveal Using Fluorescence Detection?

Even if you use CPT technology daily to test soil, you may not be aware of the further advantages CPT testing has to offer beyond its more commonly used or basic geotechnical functions. Take fluorescence detection, for example. Fluorescence detection records a fluorescent response to a specific excitation of automatic carbons in a chemical. This excitation is caused by an ultraviolet light source. But you're probably wondering how fluorescence detection can help you. Read on to find out! The Common Uses of Fluorescence Detection Before delving into scenarios in which fluorescence detection is useful, let's take a closer look at how it works in relation to CPT. One method of fluorescence detection is done using handheld UV lights to investigate above ground contamination. With CPT, the UV light source is placed in the cone, with fiber-optic cables transmitting resulting fluorescence to the surface where it can be measured in voltage responses. At Vertek CPT, we use LEDs and mercury lamps to generate UV light. Whether above ground or below, fluorescence detection reveals two ranges of fluorescent emissions: 280-450 nm wavelengths and wavelengths above 475 nm. The test is capable of detecting a variety of chemicals within these ranges, including: Polycyclic aromatic hydrocarbons (PAHs) Coal tars (DNAPL compounds) if mixed with compounds, like fuels Creosote sites that contain naphtalene, anthracene, BTEX and pyrene Total petroleum hydrocarbon values (TPH) as low as 100 ppm in sandy soil Fluorescence detection is also able to detect a number of contaminants, such as jet fuel, diesel, unleaded gasoline, home heating oil and motor oil. As you can imagine, this makes fluorescence detection extremely beneficial at fuel spill sites and sites with leaking storage tanks. However, if you already use CPT testing regularly, it's worth considering fluorescence detection in other scenarios to add capability and additional [...]

By smadi66|December 3rd, 2019|Geotechnical Arizona, Geotechnical Arkansas, Geotechnical Utah, Geotechnical Vermont, Geotechnical Virginia, Geotechnical Wisconsin, Geotechnical Washington, Geotechnical Alabama, Geotechnical Wyoming, Geotechnical West Virginia, Introductory, Cone Penetration, Soil Testing|0 Comments

Is a Sieve Analysis Accurate?

If you regularly use Cone Penetration Testing on the job, you probably already know that there are a number of alternative soil testing methods out there. Some of the more common procedures include the Standard Penetration Test, which has been covered before in this blog, and the sieve analysis, also known as the gradation test. Most commonly used in civil engineering, this basic soil testing method is used to assess the particle size distribution of soil and other granular material. But is sieve analysis accurate? As is the case with Standard Penetration Testing, sieve analysis can provide accurate results, but only in the right conditions or scenarios. In fact, sieve analysis can achieve optimal accuracy only if certain conditions are met. First off, sieve analysis needs a proper representative example of soil from the building site, meaning particles must be mixed well within the testing sample. The sample must also be of the right size, so it does not overload the sieve and skew the results. In terms of equipment, sieve analysis requires: Test sieves that conform to relevant standards Reliable sieve shaker and analytical balance Error-free evaluation and documentation Proper cleaning and care of equipment, especially sieves When these conditions are met, it is possible to get accurate and consistent results from sieve analysis, but only with coarse materials larger than #100 mesh. When it comes to finer materials smaller than #100 mesh, sieve analysis becomes less accurate. The reason for this is the mechanical energy used to move particles through the dry sieve can compromise particle size. Fortunately, this can be offset somewhat with wet sieve analysis as long as the testing particles aren't changed by the addition of water. Sieve testing is also less accurate for non-spherical particles as they may have trouble fitting through the mesh. [...]

By smadi66|December 2nd, 2019|Geotechnical California, Geotechnical Colorado, Geotechnical Virginia, Geotechnical Washington, Geotechnical Wisconsin, Geotechnical Wyoming, Geotechnical Alabama, Geotechnical West Virginia, Introductory, Soil Testing, Geotechnical Arizona, Geotechnical Arkansas|0 Comments

Intro to CPTu: What Can You Learn From Pore Pressure Data?

The most basic CPT tests classify soil based on tip resistance and sleeve friction measurements. In coarse soils and shallow testing depths, this data may be sufficient to accurately characterize the soil behavior. However, most modern CPT cones incorporate a third measurement: pore water pressure. What does this measurement mean and how can it add to our understanding of soil behavior? Pore pressure is simply a measure of the in-situ groundwater pressure, i.e. the water pressure in the “pores” between soil grains. This data is used to determine the compressibility and permeability of the soil, as well as indicating groundwater conditions. It is used to correct or “normalize” the sleeve friction and tip resistance readings in the presence of in-situ moisture and overburden stress. This is especially important in soft, fine-grained soils where in-situ moisture takes longest to dissipate, and in tests at depths greater than 100 feet. A CPT cone that is equipped with one or more pore pressure sensors is called a piezocone, and a CPT test using a piezocone is often indicated with the abbreviation CPTu. Piezocones may have between one and three pore pressure sensors, located on the cone (denoted u1), directly behind the cone (u2), or at the top of the friction sleeve (u3). Most piezocones for everyday applications use one sensor located at u2 (see image below). The pore pressure sensor consists of a porous filter (usually made of plastic resin), a small cavity of incompressible, low-viscosity fluid, and a pressure transducer. The filter and tubing between the filter and transducer must be fully saturated with fluid, usually glycerin or silicon oil, to ensure fast and accurate readings. The filter must be replaced frequently so that it does not become clogged with soil. The procedure for the CPTu test is slightly different than the [...]

By smadi66|December 2nd, 2019|Geotechnical Tennessee, Geotechnical Vermont, Geotechnical Pennsylvania, Geotechnical Virginia, CPT Data, Geotechnical Washington, Introductory, Cone Penetration, Soil Testing, Geotechnical Rhode Island, Geotechnical South Carolina, Geotechnical South Dakota, Geotechnical Texas, Geotechnical Utah|0 Comments