Geotechnical North Dakota Archives - GEOTILL provides geotechnical, construction testing and Environmental services Indianapolis Indiana

How the Concrete Vibrator Changed Concrete Mix Design

Source: How the Concrete Vibrator Changed Concrete Mix Design | For Construction Pros Over the last 60 years, concrete vibrators have evolved into a necessary machine for concrete jobs. Industry studies have highlighted separation issues, vibration energy, surface defects, and mix incompatibilities—leading to the development of a more predictive concrete placement experience. Concrete vibration dates to the late 1960s when Thomas Reading, an engineer from the U.S. Army Corps of Engineers, set vibration placement recommendations through vibration tests. At the time, the normal slump of structural concrete was three to four inches, had a “peanut butter” like consistency, and placed in forms by a concrete bucket. Reading used a larger horsepower motor to maintain a maximum vibrator speed that ran the vibrator heads for the current consistency of mixes. Reading concluded that the vibrator frequency should never exceed 10,000 vibrations per minute (vpm) due to his observation of concrete material separation. At that time, the American Concrete Institute (ACI) 309 Consolidation Guidance Specification reflected Reading’s research and limited the vibrator frequency to that maximum frequency. Surface voids were mistaken for entrapped air. Through today’s research, we’ve come to understand that surface blemishes come from vibration-frequency-forced bleed water. Ten years later, mix designs were being transformed by a chemical additive called a water-reducing agent (WRA) to allow for a more workable concrete mix for the future of economical concrete placements by pumping instead of concrete buckets. By the end of the next several decades, the volume of pumped commercial concrete reached 80%. The increased use and type of WRAs (plasticizers) allows for more possibilities of bleeding. With the increased bleeding in pumpable mixes, present concrete mix designs started to take on a "soup-like" consistency. While the vibrator design remained the same, manufacturers began to increase the amount of vibrator frequency. As [...]

By kk42|October 11th, 2021|Geotechnical Maryland, Geotechnical Wisconsin, Geotechnical Louisiana, Geotechnical Maine, Geotechnical North Dakota|0 Comments

UD researchers study climate change impacts on soils at military installations

Source: The Ground Underfoot - Civil and Environmental Engineering UD researchers study climate change impacts on soils at military installations We walk over it, drive over it and build on it. Yet, it is probably safe to say, most of us rarely think about the ground beneath our feet. Underneath the grass, concrete, asphalt and other materials in our built environment, however, soil provides structure and stability for what lies above. The United States military wants to understand the role that climate impacts, such as flooding, storm surge or sea level rise, will have on soils at its coastal military bases and facilities, which are critical to national security. Soil conditions can affect the integrity of the ground underpinning buildings, roads, bridges and more. For example, if a soil’s pH were to rise significantly, due to increased salt content-containing ions such as sodium from storm surge, it could create saline conditions that could hamper the ground’s ability to support this necessary infrastructure. Understanding these threats will enable faster and more accurate routing and maneuverability for U.S. forces. The Delaware Environmental Institute (DENIN) is collaborating with the Engineer Research and Development Center (ERDC) of the U.S. Army Corps of Engineers and Louisiana State University to understand how vulnerable military installations along coasts may be affected by soil changes due to sea level rise and coastal flooding. DENIN has received $3.79 million in first- and second-year funding from the U.S. Department of Defense to start this work, and is eligible for an additional $3.82 million in continued funding over the following two years. Led by DENIN Director Don Sparks, Unidel S. Hallock du Pont Chair of Soil and Environmental Chemistry in UD’s Department of Plant and Soil Sciences, the UD effort includes interdisciplinary collaboration with Yan Jin, Edward F. and Elizabeth Goodman Rosenberg Professor [...]

By kk42|September 22nd, 2021|Soil Testing, Geotechnical Montana, Geotechnical Minnesota, Geotechnical South Dakota, Geotechnical US, Geotechnical Kentucky, Geotechnical Nevada, Geotechnical Alabama, Geotechnical Texas, Geotechnical Arizona, Geotechnical Tennessee, Geotechnical New Hampshire, Geotechnical Connecticut, Geotechnical Utah, Geotechnical Arkansas, Geotechnical Ohio, Geotechnical New Jersey, Geotechnical Florida, Geotechnical Vermont, Geotechnical California, Geotechnical Illinois, Geotechnical New Mexico, Geotechnical Iowa, Geotechnical Virginia, Geotechnical Colorado, Geotechnical Michigan, Geotechnical New York, Geotechnical Kansas, Geotechnical Washington, Geotechnical Delaware, Geotechnical Missouri, Geotechnical North Dakota, Geotechnical Mississippi, Geotechnical Wyoming, Geotechnical Idaho, Geotechnical Georgia, Geotechnical Oklahoma, Geotechnical Nebraska, Geotechnical Louisiana, Geotechnical Maryland, Geotechnical Oregon, Geotechnical North Carolina, Geotechnical Maine, Geotechnical Pennsylvania, Geotechnical Rhode Island, Geotechnical West Virginia, Geotechnical Indiana, Geotechnical Massachusetts, Geotechnical Wisconsin, Geotechnical South Carolina, Geotechnical USA|0 Comments

Parameters Variation Model Customization and Sensitivity Analyses

Source: Parameters Variation: Model Customization and Sensitivity Analyses Parameters Variation Model Customization and Sensitivity Analyses A well-known engineering challenge in the framework of finite element (FE) analysis-based design is the large number of input factors involved in geotechnical computational models. There is always a significant amount of uncertainties associated with the properties of geomaterials, being naturally highly heterogeneous materials. In the context of model calibration and validation, conducting a sensitivity analysis is very important. This can determine the key factors which govern the system and efficiently characterize the geotechnical variability for any considered design problem. Powerful mechanisms for the consideration of parameter variation are also very interesting for speeding up FE model creation and automating results in post-processing. These are also quite useful in reducing model definition for specific types of engineering problems (excavation wall of a specific type under simple ground conditions, simple tunnel shape in uniform rock mass, etc.) to a limited number of parameters that can be inputted in a text file or Microsoft Excel spreadsheet without expert knowledge of the PLAXIS user interface and different modeling techniques and FE know-how. The sensitivity analysis and parameter variation tool in PLAXIS A sensitivity analysis determines how different values of an independent variable affect a particular dependent variable under a given set of assumptions. In other words, sensitivity analyses study how various sources of uncertainty in a mathematical model contribute to the model's overall uncertainty. The Sensitivity Analysis and Parameter Variation tool (see Figure 1) can be used to evaluate the influence of model parameters on calculation results for any particular PLAXIS FE model: The Select Parameters tab sheet will first provide information about all the parameters that can be changed to perform the sensitivity analysis. Available parameters include most model parameters of the data sets for soil and [...]

By kk42|September 21st, 2021|Geotechnical USA, Geotechnical Kentucky, Geotechnical Montana, Geotechnical Minnesota, Geotechnical South Dakota, Geotechnical US, Geotechnical Tennessee, Geotechnical Nevada, Geotechnical Alabama, Geotechnical Texas, Geotechnical Arizona, Geotechnical Ohio, Geotechnical New Hampshire, Geotechnical Connecticut, Geotechnical Utah, Geotechnical Arkansas, Geotechnical Illinois, Geotechnical New Jersey, Geotechnical Florida, Geotechnical Vermont, Geotechnical California, Geotechnical New Mexico, Geotechnical Iowa, Geotechnical Virginia, Geotechnical Colorado, Geotechnical Michigan, Geotechnical New York, Geotechnical Kansas, Geotechnical Washington, Geotechnical Delaware, Geotechnical Missouri, Geotechnical North Dakota, Geotechnical Mississippi, Geotechnical Wyoming, Geotechnical Idaho, Geotechnical Georgia, Geotechnical Oklahoma, Geotechnical Nebraska, Geotechnical Louisiana, Geotechnical Maryland, Geotechnical Oregon, Geotechnical North Carolina, Geotechnical Maine, Geotechnical Pennsylvania, Geotechnical Rhode Island, Geotechnical West Virginia, Geotechnical Indiana, Geotechnical Massachusetts, Geotechnical Wisconsin, Geotechnical South Carolina|Comments Off

A Climate Change-Induced Disaster in Denali National Park

Source: A Climate Change-Induced Disaster in Denali National Park | Time The Times has recently showcased an article on the current rockslide situation in Denali National Park. The effects of climate change have been dramatic with the current melting of the permafrost. The National Parks Service has recently upped through gravel removal of the Pretty Rocks Landslide in an effort to keep up as the rapidly thawing permafrost picks up pace. Alaska is right now recognized as the country’s fastest-warming state. The landslide hit unprecedented speed 4 weeks ago causing the team to close the back half of the park weeks earlier than anticipated. This only signals bad news as reservations are canceled in the short term and the long term implications are yet unknown. “This is the canary in the coal mine for infrastructure disruption in Alaska,” says the Camp Denali lodge owner Simon Hamm. “If things continue on the path they’re on, it’s not going to just be Pretty Rock—it’s going to be half of the Alaskan highway system.” Rapid deterioration Denali National Park is one of the U.S.’s largest national parks at 6 million acres, and sits about four hours north of Anchorage. While the entrance to the park is certainly beautiful, many people prefer to hop on buses to access the park’s marquee attractions deep down its single 92-mile road: views of Mt. Denali (formerly Mt. McKinley), the highest peak in North America at 20,000 feet; the gleaming Wonder Lake; rolling mountainsides that contain an abundance of wildlife, including grizzly bears, moose, caribou and bighorn sheep. About halfway along the road lies the Pretty Rocks Landslide, a slowly sliding section of earth that acts more like a glacier than a rockfall. Since the 1960s, permafrost deep below the earth’s surface has thawed, causing the soil and [...]

By kk42|September 21st, 2021|Geotechnical Arizona, Anchorage, Geotechnical Kentucky, Geotechnical New Hampshire, Geotechnical Connecticut, Geotechnical Utah, Geotechnical Arkansas, Juneau, Geotechnical Tennessee, Geotechnical New Jersey, Geotechnical Florida, Geotechnical Vermont, Geotechnical California, Fairbanks, Geotechnical Ohio, Geotechnical New Mexico, Geotechnical Iowa, Geotechnical Virginia, Geotechnical Colorado, Badger, Geotechnical Illinois, Geotechnical New York, Geotechnical Kansas, Geotechnical Washington, Geotechnical Delaware, Knik-Fairview, Geotechnical Michigan, Geotechnical North Dakota, Geotechnical Mississippi, Geotechnical Idaho, College, Geotechnical Missouri, Geotechnical Oklahoma, Geotechnical Nebraska, Geotechnical Louisiana, Wasilla, Geotechnical Georgia, Geotechnical Oregon, Geotechnical North Carolina, Geotechnical Maine, Tanaina, Geotechnical Maryland, Geotechnical Rhode Island, Geotechnical West Virginia, Geotechnical Massachusetts, Lakes, Geotechnical Pennsylvania, Geotechnical South Carolina, Geotechnical USA, Landslides, Geotechnical Montana, Kalifornsky, Geotechnical Minnesota, Geotechnical South Dakota, Geotechnical US, Geotechnical Alaska, Geotechnical Indiana, Geotechnical Nevada, Geotechnical Alabama, Geotechnical Texas|0 Comments

Geotechnical Instrumentation and Monitoring Consumption Market Size to Witness Huge Growth by 2027 | By Top Leading Vendors – Keller, Fugro, Nova Metrix, Geokon, Geocomp, Sisgeo, Cowi – The Daily Chronicle

Source: Geotechnical Instrumentation and Monitoring Consumption Market Size to Witness Huge Growth by 2027 | By Top Leading Vendors – Keller, Fugro, Nova Metrix, Geokon, Geocomp, Sisgeo, Cowi – The Daily Chronicle

By smadi66|September 22nd, 2020|Arlington Heights, Geotechnical Rhode Island, Geotechnical North Carolina, Geotechnical Massachusetts, Geotechnical Georgia, Geotechnical South Carolina, Geotechnical West Virginia, Geotechnical Montana, Geotechnical Maryland, Geotechnical South Dakota, Geotechnical Services, Geotechnical Nevada, Geotechnical Pennsylvania, Geotechnical Texas, Geotechnical Arizona, Geotechnical New Hampshire, Geotechnical Wisconsin, Geotechnical Utah, Geotechnical Arkansas, Geotechnical Indiana, Geotechnical New Jersey, Geotechnical Minnesota, Geotechnical Vermont, Geotechnical California, Geotechnical Kentucky, Geotechnical New Mexico, Geotechnical Alabama, Geotechnical Virginia, Geotechnical Colorado, Geotechnical Tennessee, Geotechnical New York, Geotechnical Connecticut, Geotechnical Washington, Geotechnical Delaware, Geotechnical Illinois, Geotechnical North Dakota, Geotechnical Florida, Geotechnical Wyoming, Geotechnical Idaho, Geotechnical Michigan, Geotechnical Oklahoma, Geotechnical Mississippi, Geotechnical Louisiana, Geotechnical Missouri, Geotechnical Oregon, Geotechnical Nebraska, Geotechnical Maine|0 Comments

What is a Cone Test? If you want to know the basics, start here

A Cone Penetration Test (CPT) also referred to more informally as a Cone Test, is a way to get at subsurface information without having to directly sample the subsurface. Many organizations that order drilling services are also using CPT within their operations. CPT testing services is a good support option to well drilling services, since many of the potential customers and skills overlap. What is Cone Penetration Testing? Cone Penetration Testing (CPT) is the practice of using an ASTM standard hardened cone shape that is directly pushed into the ground to substantial depths. The cone is pushed using steel rods that are able to be connected to each other in 1 meter lengths as the depth increases. A powerful hydraulic ram is used to generate a substantial amount of downward force to enable the cone to penetrate soils, sand, clay and sometimes even soft rock. In order to keep the surface equipment (truck) in place and not simply be lifted up by the ram force, the vehicles that the CPT equipment is mounted on or in are typically quite heavy. Also, the use of anchor systems to the ground will increase the ability of any vehicle mounted CPT system to push harder and therefore deeper. There are a couple of different imperative goals to any subsurface investigation. The first one is the nature and sequence of strata or soil,sediments and other geological subsurface features. Using CPT for this is called geo-technical testing. In addition, the groundwater conditions can be established during a sounding. CPT can be used to determine: the composition, strength and distribution of subsurface soils. These can range from clay, sand, bedrock, groundwater table, hydrocarbons, contaminants and more. Advantages of CPT There are many different advantages to Cone Penetration Testing (CPT), including, prompt collection and interpretation of field [...]

By smadi66|December 5th, 2019|Geotechnical Oregon, Geotechnical Rhode Island, Geotechnical South Carolina, Geotechnical South Dakota, Geotechnical Tennessee, Geotechnical Ohio, Geotechnical Pennsylvania, Geotechnical North Carolina, Introductory, Geotechnical North Dakota, Geotechnical Oklahoma|0 Comments

4 Types of Geotechnical Testing: What is the Best Option for You?

Geo-technical tests are performed by geo-technical engineers, geo-technical technicians or engineering geologists to understand the characteristics such as the physical properties that exist underneath a work site. Geo-technical testing will include a walk around of the surface conditions as well as one or more of a variety of tests. 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 sub-surface conditions to the depth desired. 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 sub-surface conditions change over various parts of the work site. A range of soil samplers can be used to extract test samples including shovels, hand-driven augers, split-spoon samplers, modified California samplers and Shelby tube samplers. Boring Borings, usually small-diameter borings, provide the opportunity to physically remove soil or rock samples for testing. Borings provide the advantage of letting you ‘see’ the actual materials, but for certain types of soils, the very act of boring can disturb the soil conditions and the samples extracted may not represent what the conditions will actually be for building and supporting structures since it is unscientific and void of actionable data. Generally, soil samples from the above tests are taken to a lab where they are evaluated. In-Situ Testing In-situ (in the situation, or at site) testing methods include penetration tests such as Standard Penetration Tests (SPT), which penetrate via drilling, and various Cone Penetration Tests, which penetrate via direct push . These tests measure the physical properties of the subsurface soil directly, without removal. This provides the advantages of generating a more accurate reflection of conditions [...]

By smadi66|December 5th, 2019|Geotechnical New Jersey, Geotechnical New Mexico, Geotechnical New York, Geotechnical North Dakota, Geotechnical Missouri, Geotechnical Nebraska, Geotechnical North Carolina, Introductory, Geotechnical Montana, Geotechnical Nevada, Geotechnical New Hampshire|0 Comments

Standard Penetration Test (SPT) a Basic Soil Testing Procedure

A widely used soil testing procedure is the Standard Penetration Test (SPT). This test is still used because of it's simplicity and low cost. It can provide useful information in very specific types of soil conditions, but is not as accurate as a Cone Penetration Test. Here's more information about this basic soil testing procedure. For this test, a sample tube, which is thick walled to endure the test environment is placed at the bottom of a borehole. A heavy slide hammer (140 lbs) is dropped repeatedly 30 inches onto the top of the sample tube, driving it into the soil being tested. The operation entails the operator counting the number of hammer strikes it takes to drive the sample tube 6 inches at a time. Each test drives the sample tube up to 18 inches deep. It is then extracted and if desired a sample of the soil is pulled from the tube. The borehole is drilled deeper and the test is repeated. Often soil recovery is poor and counting errors per interval may occur. The number of hammer strikes it takes for the tube to penetrate the second and third 6 inch depth is called the 'standard penetration resistance', or otherwise called the 'N-value'. The standard penetration resistance offers a gauge of the soil density of soils which are hard to pull up with simply a borehole sampling approach. You can imagine pushing a sample tube into gravel, sand or silt and struggling to recover samples that are useful for analysis. Coupling the standard penetration test with borehole drilling and sampling can be an improvement for understanding certain soil types underground. This basic soil testing procedure gives reasonably consistent results in fine-grained sands and is not as consistent in coarse sands or clays. It can be useful in [...]

By smadi66|December 5th, 2019|Geotechnical New Mexico, Geotechnical New York, Geotechnical North Dakota, Geotechnical Ohio, Geotechnical Oklahoma, Geotechnical Nebraska, Geotechnical North Carolina, Introductory, Soil Testing, Geotechnical Nevada, Geotechnical New Hampshire, Geotechnical New Jersey|0 Comments

See the Vertek CPT Lightweight Portable CPT Push System in Action!

At Vertek CPT we love to develop innovative, yet practical CPT solutions with real ROI. There are many situations where an ultra-mobile, yet reliable CPT push system makes a lot of sense. In areas where it is difficult to get rig-based CPT equipment into place, maybe due to the terrain, soil conditions or distance from the nearest road, a CPT system that can be carried and operated by a small crew makes sense. Maximize Your Soil Testing Service Vertek's 10 Ton Portable Cone Penetrometer Test (CPT) hydraulic load frame is the lightest, smallest, most portable hydraulic CPT unit available. The hydraulic power pack and the hydraulic cylinders are independent and coupled by hydraulic quick-disconnects. The aluminum twin cylinders and power pack weigh only 195 kg (430 lbs) and 160 kg (355 lbs) respectively. Even within this lightweight form-factor, the unit still pushes up to 10 tons, meaning that you can reach the depths necessary for many types of tests. After setting 4 sturdy augers with the included drive unit and hand tools as simple as a tape measure, you are ready to mount the unit and start pushing. You can see how easy transportation, set-up, operation and tear-down are here: [/fusion_youtube]

By smadi66|December 5th, 2019|Geotechnical Ohio, Geotechnical Oklahoma, Geotechnical Pennsylvania, Geotechnical Oregon, Geotechnical North Carolina, Introductory, Soil Testing, Video Posts, Geotechnical New Hampshire, Geotechnical New Jersey, Geotechnical New Mexico, Geotechnical New York, Geotechnical North Dakota|0 Comments

Cone Penetration Test (CPT) Overview 101

Are you new to the Cone Penetration Testing (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. What do I get from a Cone Penetration Test (CPT)? In case you're new to the Cone Penetration 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 pros and cons and different scenarios in order to make the right choice [...]

By smadi66|December 4th, 2019|Geotechnical Pennsylvania, Geotechnical North Carolina, Introductory, Cone Penetration, Geotechnical New York, Geotechnical North Dakota, Geotechnical Oklahoma, Geotechnical Oregon, Geotechnical Rhode Island, Geotechnical South Carolina, Geotechnical Ohio, Geotechnical South Dakota|0 Comments