Vertek CPT

Division of ARA

Vertek Team

4 Types of geotechnical testing: What is the best option for you?

· ·

Geotechnical testing is performed by geotechnical engineers, geotechnical technicians, or engineering geologists to understand the characteristics such as the physical properties that exist underneath a work site.

An essential part of the planning and constructing building and infrastructure projects (comprising various types of structures as a foundation, roads, bridges, excavation pit, land reclamation, beach nourishment, etc.) is the knowledge of the subsurface conditions.

The geotechnical investigation with its respective services shall be carried out. Their nature and extent depend on the structure’s type, the size of the structure, and the expected ground conditions.

Geotechnical testing is conducted by site characterization, laboratory testing, and professional interpretation of data obtained to complete the design and construction of the site improvement.

Tests generally fall into 4 categories, test pits, trenching, boring and in situ testing.

Test Pits

Test pits are much like you would expect, a pit is dug either manually or with an excavator in order to reveal the subsurface conditions to the depth desired. Generally, this is for siting shallow foundations.

Trenching

Trenching is similar to test pits except that in this case, the pit is elongated over some distance in order to establish how the subsurface conditions change over various parts of the worksite. This method allows for identification of different sedimentary changes over a longer distance.

A range of soil samplers can be used to extract test samples from these test pits for lab analysis and visual identification.

Boring

Borings, usually deployed by a drill rig and drill crew, can vary in diameter and provide the opportunity to assess density through standard penetration testing (SPT) to physically remove soil or rock samples for assessment and testing.

Borings provide the advantage of assessing field density and letting you observe the actual materials extracted. Generally, soil samples from the above tests are taken to a lab where they are evaluated. Borings offer you the opportunity to set piezometers to assess groundwater table seasonal fluctuations.

In Situ Testing

In situ testing methods include penetration tests such as Standard Penetration Tests (SPT), which penetrate via drilling, percussion-based investigation techniques, sonic vibratory drilling methods, and various static direct push Cone Penetrometer Testing (CPT).

In situ testing provides the advantages of generating a more accurate assessment of subsurface conditions allowing for better data analysis and informed geotechnical design.

The right test should be specified for the right situation or utilizing multiple tools to develop an accurate assessment of the subsurface strata. Understanding the different types of testing methods available and the advantages of each can significantly reduce uncertainties and future construction.

If you are unfamiliar with CPT, you can help your clients to understand the advantages of CPT data and expand your business by offering these services. Your clients will be able to reduce their construction risk and cost by having high resolution data, reducing their uncertainty in the subsurface conditions they may encounter.

The other investigation methods have their purpose and capabilities just as CPT does. However, CPT offers a safe, high production, high resolution data set that other methods do not.

For instance, Vertek’s Heavyweight CPT Truck is the most efficient way to collect CPT data. With a powerful seismic beam, easy to use controls, and climate-controlled cabin, this Heavyweight CPT Truck can take your site investigation business to the next level.

If you are interested in expanding your business to offer various exploration methods, CPT offers a great subsurface tool with a quick return on investment. Check out Vertek’s product page to explore what we offer.



CPT platforms designed for Cone Penetration Testing.

Vertek CPT has one goal. To make your business a success.

Download Solution Guide

General FAQs

What are the geotechnical testing types?

Geotechnical testing methods are used to get critical information about the physical properties of the substrate, rock, and soil around a potential construction site.

Types of Soil Tests for Building Construction
– Moisture content test.
– Atterberg limits tests.
– Specific gravity of soil.
– Dry density of soil.
– Compaction test

What is geotechnical testing used for in construction?

Geotechnical testing is done to investigate subsurface conditions and materials, determine the physical and chemical properties of the earth materials, evaluate slopes and soil deposits’ stability, assess the risks posed by site conditions, design foundations, and monitor site conditions and foundation construction.

Who uses geotechnical testing?

Geotechnical engineers use tools, such as the cone penetration test (CPT), to estimate the amount of skin and end bearing resistance available in the subsurface. There are many types of foundations, including piles, caissons, piers, drilled shafts, and earth stabilized columns.

Why is geotechnical testing performed?

Geotechnical testing is conducted by geotechnical
engineers, geotechnical technicians, or engineering geologists to understand the characteristics, such as the physical properties that exist underneath a work site.

In Situ Soil Testing 101: The Different Types of Tests

· ·

Exploring adding in situ soil testing to your geotechnical operations? Already doing in situ and want to find the right tools for the job? Vertek has you covered.

In this post, we will take a deep dive into a few different types of soil tests that can be performed in situ. First, let’s start with “why do you conduct in situ soil testing?”

In situ soil testing is essential for gaining soil property information, measuring groundwater pressure, gathering moisture content data, and other essential data points, all in which can be safety-critical in many different instances.

In situ soil testing can be accomplished in a variety of different ways. Every soil test has its place and benefit; however, the most accurate and thorough in situ soil testing for determining a wide variety of technical attributes is Cone Penetration Testing (CPT).

Just like everything else, determining what is best for your business requires understanding the pros and cons of every possible solution, in this case, an in situ soil testing solution.

Options for in situ soil testing procedures

Here is a closer look at a few different options for performing an in- situ soil test:

Standard Penetration Testing (SPT) and in situ soil testing:

This option is dynamic, low in cost, and has been widely recognized as a simplified solution that provides useful information.

While it’s reasonably consistent with its fine-grained sands results, it’s not as consistent with coarse sands or clays, which can be difficult for gathering accurate data and analysis of soil conditions.

For even more on Standard Penetration Testing, visit one of our previous posts that takes a closer look at SPT for your business.

Dynamic Cone Penetrometer (DCP):

With a DCP test, the cone is driven by a standard amount of force from a hammer, and how far the cone moves with each blow is used to determine the soil density and properties at that level. It will record the number of mm per hit and gather an estimate of different soil properties.

Since DCP is essentially hand-powered, it is cheaper and more portable than CPT equipment, but the possibility of human error makes it trickier to obtain consistent and accurate data.

Historically, one of the largest difficulties associated with DCP has been obtaining accurate depth difference measurements with a hand rule after each blow of the hammer.

Fortunately, handheld electronics technology has alleviated these issues to a great extent. Vertek’s Handheld DCP System uses a smartphone app and a laser rangefinder to automatically count blows and measure, record, and plot depth. From the smartphone, this data can be easily graphed in the field and transferred to a computer or client for reporting and analysis.

To further increase the repeatability and efficiency of DCP testing, Vertek offers automatic DCP (ADCP) testing systems. ADCP rigs can be mounted on lightweight trailers, commercially available trucks, or ATVs.

Automated tests are both faster and more consistent than their manual counterparts, and also decrease physical labor for the operator.

Cone Penetration Testing (CPT):

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 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.

This type of testing is not only accurate, but it can collect data at a fast rate and, from there, will interpret the data on the site, enabling you to gain a competitive advantage as an engineer.

Whether you purchase a Vertek CPT truck rig, SmartDCP, drilling rig CPT conversion kit, or CPT cones, you can operate reliably in the most demanding conditions. Contact us to discuss your needs and our solutions.



CPT platforms designed for Cone Penetration Testing.

Vertek CPT has one goal. To make your business a success.

Download Solution Guide

Have questions about Vertek’s solutions for in situ soil testing?

Click here or give us a call at 1-800-639-6315 to discuss your needs and our solutions.

Geotechnical Services: Learn How to Grow Your Business

· ·

If you’re looking for ways to help grow your business, consider expanding your geotechnical services. By increasing the geotechnical services your company offers, you’ll be able to expand your current client base and increase your workload.

To realize these benefits, you’ll first have to decide which geotechnical services you can offer, which you could offer more in-depth, how it would affect your current workload, and how it can increase your revenue. 

What geotechnical services can your business offer?

  1. Rental and sales of CPT equipment.
  2. Field exploration (soil and rock sampling, test boring, core drilling, electro-magnetic surveying, etc.).
  3. Site evaluation (for pavement/ subgrades, alternative site and route studies, the definition of critical geotechnical parameters).
  4. Engineering analysis and design (slope stability evaluation, hillside grading recommendations, earth retaining structure design, earthquake damage analysis).
  5. Laboratory testing services (soil classification, shear strength, permeability, consolidation characteristics, resistivity).

Some of these services may be a more natural fit for your current business than others. However, it’s worth considering the environment your business is located in, as well as the environmental factors that have an affect on construction. This will help you to hone in on the services that are in demand. 

Also research any potential competition in your area to see what they do or do not offer, and consider filling any void you discover.

For example, if you notice a void in your area’s laboratory testing services, consider hiring an expert internally. Between the equipment and manpower you already hold, adding an additional employee may prove profitable.

If you’re not sure how to gauge demand in your area, consider who you could be marketing your geotechnical services to.

Potential customers include:

  • Commercial and residential real estate developers
  • Realtors
  • Architects
  • Geotechnical and civil engineering firms
  • Concrete and foundation specialists
  • Bridge builders
  • Construction companies
  • Utilities
  • Manufacturing companies
  • Financial institutions
  • Federal, state and municipal organizations

With a little research and a keen eye, you may be able to spot some great opportunities to grow your business with expanded geotechnical service offerings!

We are here to help with your geotechnical needs!

Click here or give us a call at 1-800-639-6315 to discuss your needs and our solutions.

General FAQs

What is Advanced Geotechnical Methods in Exploration (A-GaME)?

Mitigate risks and improve reliability by optimizing geotechnical site characterization with proven, effective exploration methods and practices. Up to 50 percent of major infrastructure projects suffer impacts to schedule or cost due to geotechnical issues.

What are geotechnical services?

Geotechnical Aspects of Pavements. Many groups within an agency are involved with different aspects of the definition, design, and construction verification of pavement geo-materials. These groups include pavement design engineers and geotechnical engineers.

What are the geotechnical aspects of pavements?

Familiarity with geotechnical aspects of pavement engineering is essential for the practicing pavement engineer. When designing pavements, accurate characterization of the existing sub-grade condition becomes a crucial task. In the past, traditional geotechnical exploration and testing methods have been used to characterize existing sub-grade conditions.

What are geotechnical site characterizations?

Geotechnical site characterization is a systematic study conducted to collect data regarding in-situ ground conditions. With site characterization, engineers estimate the geotechnical parameters necessary for efficient and cost-effective geotechnical engineering analysis and design.

Get the Vertek Product Catalog

Work with the world leader in the development and manufacturing of advanced in-situ soil testing apparatus.

Download Product Catalog

What is DCP testing and how does it compare to CPT?

· ·

Dynamic Cone Penetration (DCP) testing is used to measure the strength of in-situ soil and the thickness and location of subsurface soil layers.

Dynamic Cone Penetration

It is similar to CPT (cone penetration testing) in that a metal cone is advanced into the ground to continuously characterize soil behavior.

In DCP, however, the cone is driven by a standard amount of force from a hammer, and how far the cone moves with each blow is used to determine the soil density and properties at that level.

In DCP testing, the pushing force is applied by manually dropping a single or dual mass weight (called the hammer) from a fixed height onto the push cone unit.

dcp data

The resulting downward movement is then measured. Unlike CPT systems, basic DCP equipment is hand-portable and may be limited to test depths of 3-4 feet: this makes it a good choice for shallow testing applications such as roadbed construction and maintenance.

Since DCP is essentially hand-powered, it is cheaper and more portable than CPT equipment, but the possibility of human error makes it trickier to obtain consistent and accurate data.

Historically, one of the largest difficulties associated with DCP has been obtaining accurate depth difference measurements with a hand rule after each blow of the hammer.

As you can imagine, taking these measurements by sight and recording them by hand can be slow, finicky work.

Plus, to measure the total depth, the sum of these measurements is calculated, so it is easy to accumulate a troublesome amount of error if each measurement is even slightly off.

Fortunately, handheld electronics technology has alleviated these issues to a great extent. Vertek’s Smart DCP System uses a smartphone app and a laser rangefinder to automatically count blows and measure, record, and plot depth.

From the smartphone, this data can be easily graphed in the field and transferred to a computer or client for reporting and analysis.

Automatic data collection saves time, increases accuracy, and means that the test can be efficiently completed by one person.

vertek automated dcp testing

To further increase the repeatability and efficiency of DCP testing, Vertek offers automatic DCP (ADCP) testing systems. ADCP rigs can be mounted on lightweight trailers, commercially available trucks, or ATVs.

Automated tests are both faster and more consistent than their manual counterparts, and also decrease physical labor for the operator.

DCP and ADCP testing and data analysis is a broad subject, so we’ll return to it in another blog.

In the meantime, be sure to check out the DCP testing information and video demonstrations on our site! You can also download our catalog to see the full specifications and capabilities of Vertek’s Smart DCP and ADCP equipment.

Have questions about whether DCP is right for you?

Click here or give us a call at 1-800-639-6315 to discuss your needs and our solutions.

DCP FAQs

What is a dynamic cone penetrometer?

The Dynamic Cone Penetrometer (DCP) is used to determine underlying soil strength by measuring the device’s penetration into the soil after each hammer blow.

How does a cone penetrometer work?

A cone penetration test rig pushes steel cone into the ground, generally up to 20m below the surface or until the cone reaches a hard layer. The steel cone contains an electronic measuring system that records tip resistance and sleeve friction.

What is DCP testing?

Dynamic Cone Penetration (DCP) testing is used to measure in-situ soil’s strength and the thickness and location of subsurface soil layers. It is similar to CPT in that a metal cone is advanced into the ground to characterize soil behavior continuously.

What is DCP in the construction industry?

Dynamic Cone Penetrometer, or DCP, is a tool used for evaluating the strength of soils on site. It also helps with monitoring the condition of granular layers and subgrade soils in pavement sections over time.

Get the Vertek Product Catalog

Work with the world leader in the development and manufacturing of advanced in-situ soil testing apparatus.

Download Product Catalog

How to Interpret Soil Test Results from CPT Testing

· ·

Even if you already have a solid grasp of what Cone Penetration Testing is and how CPT rigs test soils, understanding soil test results is a bigger task.

You likely already know that CPT rigs are equipped with automated interpretation programs, but that doesn’t mean test results are easily readable right away.

Fortunately, even if you aren’t a technician, it is possible to gain some understanding of soil test results. Read on to find out how. 

The basics of soil test results

At the most basic level, the results of CPT testing are based on the relationship between cone-bearing, sleeve friction, and pore water pressure.

With these three measurements, you can learn quite a bit about soil composition and conditions. For example, the friction ratio measured by the sleeve is used to determine the soil type. Soil is then classified according to the Unified Soil Classification System (USCS).

CPT can also measure:

  • Soil parameters
  • Computer calculations of interpreted soil behavior types (SBT)
  • Additional geotechnical parameters

It’s also possible to determine temperature shifts and zero loads offset through the use of baseline readings. This essentially means comparing test results to those generated from initial testing before work begins on a site.

With careful observation, it’s possible to determine even more about the soil tested.

Some examples include noting trends in water content to determine the type of soil (ie, sand does not retain water as well as clay) and knowing that larger values of cone resistance and sleeve friction usually indicate coarser soils, while lower values tend to indicate fine-grained soils.

Although they won’t put you on the level of a trained technician, these basics should make soil test results much easier to understand. More importantly, with this information in mind, you should have a much greater understanding of CPT testing as a whole.

When Should You Consider CPT Testing Over SPT?

· ·

CPT Testing vs. SPT Testing

What is CPT Testing?

Cone Penetration Testing (CPT) is a significantly faster, safer and offers digital in-situ soil behavior type (SBT) instantly. The in-situ data gathered can inform geotechnical design and field characterization decisions immediately. CPT’s versatility in obtaining shear wave velocity, sediment pore pressure dissipation, and discrete sampling offers users increased functionality and digital sounding files.

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 in general is three times as fast as SPT site characterization; tripling your productivity and reducing your inderived waste generated (cuttings).

The data generated can be exported and utilized in multiple modeling softwares to accurately assess risk in design and inform geotechnical decisions. CPT data offers high resolution in-situ results versus SPT which often utilizes variable intervals and limited grab samples from various depths.

Vertek was born out of conducting field CPT services and has transitioned into a leading manufacturer of robust and reliable CPT sounding systems and data acquisition equipment.

For example, Vertek’s S4 CPT Sounding System is a versatile , affordable push system that is compatible with construction equipment and can have a dedicated trailer system. The S4 is capable of providing superior soil testing almost anywhere SPT Testing can be performed.

Additionally, if your organization utilizes SPT for site characterization a small capital investment into a CPT Drill Rig Conversion Kit allows you to quickly conduct CPT testing and offer both services to your customer.

What is SPT Testing?

Standard Penetration Test (SPT) is a low-cost and straightforward testing procedure widely used in the geotechnical examination to determine the relative density and angle of shearing resistance of cohesionless soils and also the strength of stiff cohesive soils. 

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.

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.

Want to learn why CPT is the preferred method for site characterization? Read how Summit Geoengineering uses Vertek’s Drill Rig Conversion Kit.

Click here or give us a call at 1-800-639-6315 to discuss your needs and our solutions.

Cone Penetration Test (CPT) Overview 101

· ·

Learn the basics of a cone penetration test with this CPT overview 101

Are you new to the Cone Penetration Test (CPT) business? Or maybe you’re looking to convert your operation to CPT?

Wherever your interest is surfacing from, we have everything you need to know about expanding into the CPT business with confidence.

It’s important to understand cone penetration testing for in geotechnical practice and understand the cone penetration testing equipment. CPT equipment like CPT rigs, CPT drilling rig, and other CPT testing equipment.

What is Cone Penetration Testing?

soil compaction test

The cone penetration or cone penetrometer test (CPT) is used to determine the geotechnical engineering properties of soils and delineating soil stratigraphy.

What do I get from a CPT?

In case you’re new to the Cone Testing business, CPT will collect important subsurface information from standard tests and then from there determine important business factors, such as, how to design foundations for structures or the composition of subsurface soils.

The difference between this type of data collection and other competitors is the benefit CPT has for businesses.

CPT can provide immediate, onsite information that is quick and accurate. Above all, onsite results can improve your business productivity; ultimately leading to a more efficient business process.

If you had the chance to take a look at our Solutions Brief: Enter the Cone Penetration Business with Confidence, then you may have already taken a deep dive into the advantages of collecting subsurface information with a process that is more quick and efficient than other options. 

Businesses are choosing to use a CPT solution for many different reasons; whether for construction or government purposes, they all benefit from the same advantage: speedy collection and interpretation of data, a safe solution for operators and the environment, and the ability to adapt to different weather and soil conditions.

We understand how intimidating it can be to enter a new business; large or small. That’s why we are focused on delivering educational content that addresses all of your CPT needs and concerns.

From topics on ‘What is a Cone Test‘ to ‘Mud Rotary Drilling vs. CPT,’ it’s important to consider the pros and cons and different scenarios in order to make the right choice for your business. 

For more on expanding into the CPT business, subscribe to our blog or take a look at the video below to see just how easy it is to transition into the CPT business and start maximizing your profit.

General FAQs on Cone Penetration Testing

What is a cone penetration test?

The cone penetration or cone penetrometer test (CPT) determines soil’s geotechnical engineering properties and delineating soil.


What is a cone penetration testing?

The cone penetration test has become internationally one of the most widely used and accepted test methods for determining geotechnical soil properties.


How does cone test work?

The steel cone contains an electronic measuring system that records tip resistance and sleeve friction. As the cone is pushed into the ground, the soil responds with differing degrees of resistance. This resistance is recorded using force sensors in the tip.


What is the purpose of the cone penetration test?

A cone penetration test is used to determine the geotechnical properties of soils. The CPT has become internationally one of the most widely used and accepted test methods for determining geotechnical soil properties.

Get the Vertek Product Catalog

Work with the world leader in the development and manufacturing of advanced in-situ soil testing apparatus.

Download Product Catalog

Why do Dynamic Cone Penetration (DCP) Testing?

· ·

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 failures such as large cracks, potholes, and displaced pavement. Assessing the compaction of non-cohesive soils such as fine sands is a particularly 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.

This is where dynamic cone penetration (DCP) testing comes in. Read on to learn more about the importance of DCP testing and what solutions are available. The Dynamic Cone Penetration (DCP) test 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 CPT and is more expensive due to the need to drill boreholes and the time and labor to do each sample test.

Cone Penetration Testing is a more efficient and accurate way to assess soil density at depth. However, for a small number of shallow tests, dynamic cone penetration testing will provide a more accurate result than SPT and will be less expensive than hiring a CPT rig.

Nuclear Density testing requires a radiation source such as Cesium or Radium. The instrument emits a beam of particles that either are reflected back or pass through whatever is being tested for density.

Using a calibrated sensor and gauge the density of a variety of different materials, including soils, can be determined.

While Nuclear Density testing is relatively efficient because it uses radioactive materials operators must be specially trained and licensed. It is also riskier to manage at a worksite, which again is a good reason to consider DCP.

DCP uses a cone similar to CPT, which provides specific advantages in how the instrument behaves in the soil while measurements are being taken vs. SPT.

Because SPT readings are taken at defined depth and the output is ‘how many blows to travel a specific distance, the test is limited in scope. DCP testing by contrast can reveal a more continuous profile as the tool is driven deeper into the soil to a maximum depth of one meter.

Vertek’s Smart DCP kit and Automated DCP system gives users the ability to conduct three and eight times the number of tests, respectively, compared to standard DCP testing.

So for certain specific test scenarios, dynamic cone penetration can be the test of choice. It is generally more accurate at assessing soil density (compaction) than SPT, is less expensive for certain applications than CPT and is safer and less complicated to administer than Nuclear Density testing.

While DCP results will be consistent for a specific set of soil conditions, it is recommended that the test be calibrated to a specific geology to ensure that data interpretation is accurate.