Vertek Team

Subsurface site characterization is a high-resolution technology that when deployed can greatly enhance your information regarding soil strength and properties. Cone penetration testing (CPT) is an advanced method of geotechnical investigation that is efficient and reliable and can provide engineers with the information needed to mitigate risk. CPT can accurately determine soil types and strength, the groundwater table, and assist with identifying the location of any liquifiable materials or voids. By understanding the benefits of CPT, you can make informed decisions about improving your site conditions and achieving a successful outcome. So, why should you choose CPT over other methods? Keep reading to find out. 

The ROI of Cone Penetration Testing 

CPT offers a significant return on investment. Because of efficient and effective data collection, CPT significantly reduces the time and cost compared to traditional drilling methods. With adaptable systems such as Vertek’s S4 Sounding System and Drill Rig Conversion Kit, operators can use existing construction equipment or drill rigs, respectively. Vertek owners have reported a full return on investment in as little as 40 working days. Download our ROI calculator to estimate how fast you can earn your money back and begin churning a profit.  

Utilize a Hybrid Site Investigation 

CPT is also an effective tool for hybrid site characterization, combining physical and digital methods. It is not uncommon for engineers to request multiple investigation methods be utilized at a specific site. For instance, standard penetration testing (SPT) and CPT are often used in conjunction. SPT provides the physical collection of soil and “N”-value, whereas CPT uses a sensored probe with a conical tip that collect and measure three main measurements; tip resistance, sleeve friction, and pore pressure. With these series of sensors you can calculate:  

• “N”-value 
• Overburden 
• Effective overburden 
• Undrained shear strength 
• Over consolidation ratio 
• Friction angle 
• Pore pressure ratio 
• Coefficient of earth pressure 
• Young’s Modulus 
• Poisson’s Ratio 
• Relative density 
• Hydraulic conductivity 
• Normalized uncorrected tip stress 
• Normalized corrected tip stress 
• Normalized friction ratio 
• 1986 friction ratio behavior type 
• 1990 friction ratio soil behavior type 
• Preconsolidation stress 
• QCI 
• Fines content 
• Classification index  

Users with a drill rig can easily add CPT via the Drill Rig Conversion Kit.  

Utilize the Highest Quality Data 

With Vertek’s industry-leading CPT software, real-time in-situ data is displayed clearly on the user interface. The high-quality data collected is immediately available for processing, as opposed to physical collection methods which require analysis at a laboratory. Vertek CPT software offers real-time visuals of four of the 13 data collection channels and data points every five millimeters. Data files can be processed for visual or text measurements for each line of data to the end of exploration. 

In conclusion, CPT is a trusted and effective method for collecting high-resolution geotechnical data. CPT can provide significant cost savings through efficient data collection. CPT is also an effective tool for hybrid site characterization to determine if ground improvement or stabilization techniques are required. If you’re looking to implement cone penetration testing, choose equipment built by former CPT providers. Choose Vertek. Contact us for a quote.   

Vertek equipment is proudly designed, manufactured, and serviced in the United States. As former CPT providers, we know the importance of having reliable support while you are in the field, and it’s why we are always just a phone call away for the life of your equipment. 

Over the past ten years, there has been a dramatic decline in infrastructure spending, but that has changed with the investment of nearly $2 trillion into infrastructure. As local, state, and federal agencies plan projects, you can leverage cone penetration testing (CPT) to help contribute to the development of US-based infrastructure and increase your revenue.  

The United States has a history of building its way to prosperity, with canals, railroads, and highways that served as pathways for people and commerce. Today, infrastructure includes high-speed internet networks, airports, ports, power grids, and other systems crucial to economic vitality. With major infrastructure projects planned across the nation, CPT can help to ensure those projects are done right and will be effective for years to come. Some of the benefits of using cone penetration testing with infrastructure development include: 

• Identifying potential risks earlier rather than later. 
• High resolution subsurface site characterization. 
• Reduction in engineering safety factors on projects. 
• Preventing unexpected delays while saving considerable time and money. 
• Information that can be crucial when developing infrastructure projects that are high-risk or high impact. 

By understanding the latest trends in US infrastructure development, you can identify opportunities to expand your business. 

U.S.-based Infrastructure Trends in 2022 

With an infrastructure score of C-minus, it is clear there is much work to be done to improve America’s aging infrastructure. Take bridges for example. The ASCE reports that 178 million trips per day are taken on bridges that are “structurally deficient.” Similarly, America’s “deteriorating roads are forcing the nation’s motorists to spend nearly $130 billion each year on extra vehicle repairs and operating costs.” 

Climate change is also expected to significantly impact infrastructure. Weather can affect soil characteristics by causing things like erosion, which can significantly weaken currently built and future infrastructure projects. CPT can help with the design of infrastructure projects both onshore and nearshore which are particularly susceptible to these conditions. 

The U.S. Congress and Biden Administration recognized America’s need for a significant infrastructure investment in passing the “Infrastructure Investment and Jobs Act” in 2021. Some $350 billion is allocated to highway programs alone through 2025. Another $17 billion is to be spent on improving port infrastructure and waterways. Many of these projects will require CPT testing and design before building new structures or improving older ones.  

Improving Infrastructure Development with Cone Penetration Testing 

CPT is an easy and accurate method of investigating sediment during the planning stages of infrastructure development. CPT data helps prevent future problems with dams, bridges, buildings, energy transmission lines, airports, and other infrastructure projects. Forward-thinking CPT investigations can prevent unexpected delays and saves considerable time and money in infrastructure development.  

The future of the US infrastructure is bright. Vertek offers solutions that save thousands in subcontractor costs based on your scope of work. We work with various industries to improve their capabilities by offering our expertise in cone penetration testing for geotechnical engineering projects to enhance future structural projects. If you are new to CPT, or wanting to grow your existing CPT business, check out The Business of CPT.  

As former CPT providers, we build systems that are easy to use, and built to last. Whether you need something smaller and modular, or a heavy-duty CPT truck, we have a solution for you.  

Contact us today to discuss your needs and our solutions.  

Vertek equipment is proudly designed, manufactured, and serviced in the United States. As former CPT providers, we know the importance of having reliable support while you are in the field, and it’s why we are always just a phone call away for the life of your equipment. 

When VTrans (Vermont Agency of Transportation) personnel undertook the bridge replacement project at the interchange of I-89, US 2 and US 7 in Colchester, they knew they would need to bring their A-GaME. The agency had used Cone Penetration Testing (CPT) in the past to supplement traditional boring methods, but based on its understanding of the regional geology, site history and perceived likelihood of encountering soft clay deposits, they decided to incorporate CPT as a key component of the subsurface investigation for the project.

According to Stephen Madden, geotechnical engineer at VTrans, the use of CPT to provide high-quality and near continuous data had the following benefits:

• Aided in seismic site classification
• Improved estimation of undrained shear strength
• Allowed for direct design of driven pile foundations
• Allowed for a higher resistance factor to be selected for stability analyses, resulting in a more efficient foundation design

The geotechnical investigation program included CPTu, Seismic CPT (SCPTu) and traditional borings. (The “u” indicates that pore pressure measurements were taken). The boring/CPTu location plan was created such that CPTu locations were adjacent to borings at the planned bridge abutment locations and near the I-89 northbound US 2 interchange. CPTu soundings replaced borings along the I-89 southbound off ramp to US 2. The CPTu locations were strategically selected for areas where deep glaciolacustrine clay was anticipated to potentially influence the seismic design of the bridge at infrastructure components, and where the presence of tall embankment fills could lead to settlement and stability issues.

“The data obtained from the CPTu and SCPTu were used to justify selecting a higher resistance factor for stability analyses of the MSE walls at the proposed abutment locations due to the well-defined subsurface stratigraphy and geotechnical parameters,” explains Madden. “Additionally, we were able to use the measurements from the SCPTu soundings to designate a Seismic Site Class of D and Seismic Performance Zone 1, both of which resulted in time and cost savings in the design of the replacement structure over traditional borings alone.”

While the use of CPT offered several benefits to the site investigation and subsequent analysis and design for the project, there were challenges including the presence of obstructions, identification of the refusal layer, and execution of dissipation testing in low-permeability clay. Lessons learned from these challenges will be helpful for future projects in similar soils.

In the end, CPT provided value above and beyond that of SPT borings due to the continuous profile and the improved reliability that the CPT data provided. What’s more, the CPT program was implemented over a single day and resulted in direct costs savings of $6,025.

So, what’s the key takeaway according to VTrans?

When developing a geotechnical exploration program, it is critical to understand the capabilities and limitations of the exploration technology and the specific characteristics of the project site. One size does not fit all! The reward for this effort on the I-89 interchange project was the time and cost savings realized for VTrans that resulted from a successful and efficient exploration program.

Information for this article was provided by Stephen Madden of VTrans, and Melissa E. Landon, Ph.D., P.E., and Chris Benda, P.E., of Golder Associates USA Inc., Member of WSP.

Original source: U.S. DOT Federal Highway Administration. June 14, 2022 newsletter

Nations are racing to increase renewable energy production and the United States in no different. According to data from the U.S. Energy Information Administration, renewable energy production doubled between 2000 – 2020. While wind turbines and solar fields seem to pop up overnight, there is immense preparation before they are established. Part of this preparation is a site investigation to understand what soil conditions exist and what mitigation efforts need to be taken to support the construction of these massive structures and the equipment access to transport and construct them.

This is where cone penetration testing (CPT) comes in. CPT can help identify potential weak spots in the sediment deposits that could lead to slope failure, such as equipment or foundations in non-cohesive materials. By identifying potential problems in advance, engineers can take steps to correct them and ensure that the entire project is a success.

Use of CPT in Clean Energy

CPT is a type of soil testing that involves using a conical-tipped probe to measure the resistance of soil during penetration. CPT is used extensively in the evaluation of soil for clean energy projects. It is used to study the seismic shear wave impact of earthquakes in soil and evaluate the strength and stability of earth structures and dams.

Additionally, CPT can be used to assess the suitability of sediments for the installation of wind turbines and solar panels, as well as the strength of the soil where heavy equipment such as cranes need to travel. Ensuring that the soil is suitable for these installations can be critical to their longevity and potentially reduce risk and costs incurred due to unstable soil conditions or failures. CPT is an efficient and cost-effective subsurface investigation method to ensure a high-resolution site characterization.

Wind

CPT is an essential tool for assessing soil suitability for clean energy projects. Typically, CPT investigations for wind energy systems can help to ensure that the foundations are adequately designed for the existing sediment. CPT data is also leveraged to build temporary roadways capable of supporting the weight of turbines and cranes. Given the large swaths of land used for wind turbines, Vertek’s CPT trucks are perfect for maximizing production. 

As part of the design or pre-construction phase of a wind turbine project, CPT can help ensure that selected wind turbines are constructed to minimize the risk of foundation failure. It can also help identify areas where the combination of sediment type and groundwater may need to be considered. Utilizing Standard Penetration Testing (SPT) technologies may miss these subsurface zones leading to additional maintenance or construction costs down the road. Overall, CPT site investigations can better inform the design and construction saving money and schedule for a project.  

Solar

CPT is a valuable tool that can assess the soil properties at a spot where solar energy technology is being considered. CPT can help inform solar designers determine the suitability of a location for this technology by providing information on the soil strength, moisture content, and density.

CPT operators investigating solar sites which are often shallow investigations on undeveloped sites prefer a modular system like Vertek’s S4 CPT Sounding System. The S4 push frame can be attached to various types of standard construction equipment and shipped between job sites with other construction equipment. The S4’s modularity, size, and power are perfect for accessing challenging terrain with existing construction equipment.

CPT Supporting Renewable Energy Infrastructure

The U.S. Energy Information Administration “projects that the share of renewables in the U.S. electricity generation mix will increase from 21% in 2020 to 42% in 2050.” This will require an enormous expansion of renewable energy infrastructure that will require high resolution and efficient subsurface investigations. Engineering and construction firms’ number one goal is to mitigate risk and with Vertek CPT systems, you can deliver the data they need to reduce their project design and construction risk.

Check out our full product line here. New to CPT? Download The Business of CPT.