Studying the ground under your feet: Interview with Taylor Hall about rock and soil stability

Source: Studying the ground under your feet: Science Moab speaks with Taylor Hall about rock and soil stability | Get Out & Go | moabsunnews.com Moab is renowned for its biological soil crusts, but what’s happening underneath all that crusty black — with the soil and rock itself? This week, we speak with geotechnical engineer Taylor Hall, owner of the Moab Geotechnical Group, about soil mechanics, engineering tools, and how he decided — at age 15, in a McDonald’s — to start working with the dirt. Science Moab: What is geotechnical engineering? Hall: Geotechnical engineering generally deals with rock and soil mechanics and physics: how those materials will respond to structures or just how they respond to gravity. We might look at something like a bridge to understand its foundations, or we might look at a landslide that gets triggered by natural causes. We’re fortunate to be able to come in there and tell you how things are responding and why and what to expect. Science Moab: How do you test soil? Hall: When geotechnical engineering got its feet in the 1940s and 1950s, they would sample soil by drilling a hole and driving a sampler into the ground using a fixed-weight hammer. Using that method, we were able to acquire a sample and get some resistance associated with that sample. That's much of what we do today, but we do it now because it's backed by 60 or 70 years’ worth of empirical relationships. Generally, you're only dealing with one or two such holes, and you have to use them to characterize a whole site. It's tough, but that's why I chose geotechnical engineering: because no two sites are the same. It provides the opportunity to really think on your feet. Science Moab: Once you’ve taken measurements, how do [...]

Drone Rules Make Tracking Down Faults a Difficult Feat

Chelsea Scott looks on as Michael Bunds lands a fixed-wing drone in Southern California. Credit: Jui-Chi (Vickie) Lee Source: Drone Rules Make Tracking Down Faults a Difficult Feat - Eos Chelsea Scott and Ramón Arrowsmith, like many earthquake scientists, track down faults. As tectonics researchers at Arizona State University, they need to know where a fault is, how much it’s moved, and how it behaves below the surface. Small uncrewed aerial systems, also known as drones, provide them with high-resolution photographs that capture the necessary information at the scale of centimeters—a higher resolution than some commonly used, easily accessible satellite or airborne data sets. However, collecting drone data along the length of a fault is no simple task. Bigger Is Better A magnitude 7.0 earthquake can produce a 62-mile-long (100-kilometer-long) rupture with surface displacements of up to about 3 feet (1 meter), said Arrowsmith. “You need to have a good enough ruler to measure [that],” he said, which imagery collected from drones can easily provide. The problem, he said, is rapidly covering a 62-mile stretch. Nearly every country that regulates drone operations recommends or requires that pilots maintain visual contact with their drone. One way around the problem is to use a bigger drone. Cheap, heavy quadcopters—helicopters that can easily take off and land—are small compared with lightweight, expensive fixed-wing drones that look like tiny airplanes. In February 2020, Scott and three colleagues spent almost 4 days mapping 25 miles (40 kilometers) of the San Andreas Fault in Southern California. Although they had quadcopters, Scott said “the workhorse was the fixed-wing drone.” “Because fixed-wing drones are so expensive, flight planning is done very, very carefully, and unfortunately the project is over if the drone crashes.” The average quadcopter can be spotted approximately half a mile (0.8 kilometer) away; mapping long linear features like [...]

Landslide Prevention Near Sussex

Source: 'An engineering feat': Why this key section of railway is closed | ITV News Meridian Network Rail describes it as engineering feat, a two week project to stabilize three sections of Victorian railway embankment between Brighton and Hove. Until Saturday October 2nd 120 workers each day are working from up to 15 meters high to install rock bolts, soil nails and netting. All three interventions are designed to protect debris falling onto the tracks. In recent years landslides have led to significant delays for passengers on the network and climate change has made the chalk cutting incredibly vulnerable. Project manager, Tom McNamee says, "We've seen previously catastrophic failures of the embankment and that’s an unplanned failure, we have loose material fall onto the railway and that becomes a danger to trains and essentially we have to close the line in an unplanned, unexpected manor. "We really would like to thank our lineside neighbors, it is a massive inconvenience, we are using chainsaws and rock drills, loud and noisy equipment, right at the. Back of their properties for 14 days but we’re working closely with them and taking in all their concerns and considerations. If we were unable to do this work over 14 days we would have to do this over 12 weeks of night work and that would obviously have a bigger impact on the lives of people living here." 1,012 rock bolts being installed 1,000 soil nails being drilled in £5 million spent on the project Traveling between Brighton and Hove? This is what you need to know Trains between Brighton and London are unaffected No trains will run directly between Brighton and Hove/stations towards Littlehampton Trains will run to an amended timetable between Preston Park and Littlehampton and between Littlehampton and Portsmouth Harbour/Southampton Central Southern passengers will [...]

Researchers in Tasmania design special drill for million year old ice core project

Source: Researchers in Tasmania design special drill for million-year old ice core project to help find answers to climate crisis | The Singleton Argus | Singleton, NSW Answers to the world's climate crisis may be discovered in a 2.8 kilometer pole of million-year-old ice that is set to be extracted from Antarctica and delivered back to research labs in Tasmania for atmospheric testing. Australian Antarctic Division researchers in Tasmania have designed and manufactured a 400-kilogram drill for the million year old ice core project which is capable of operating in minus 55 degree temperatures. It will bore down into 2.8 kilometers of ice, which is believed to be up to 1.5 million years old, to extract three meter sections of ice, or ice core, at any one time. Up to 8 tons of ice will then be brought back to research labs for AAD researchers to extract data and information about past temperatures, sea ice levels and wind patterns in Antarctica. Australian Antarctic Division engineers spent two months preparing blocks of ice that would replicate Antarctic ice, which were then used to test the specially designed drill. Picture: Australian Antarctic Division   It will also be used to answer a "long standing mystery" in Antarctic research about the frequency of ice ages. The project is part of this year's Antarctic research season which has been dubbed the most ambitious season that the AAD have ever undertaken, with 500 scientists and up to 800 tons of cargo to be shipped to Antarctica. Australian Antarctic Division chief scientist Nicole Webster said the million year ice core project is an incredible milestone for climate research. She said layers in the ice core are like "pages in a diary", where tiny air bubbles trapped in the ice core contain atmosphere and other [...]

Dynamic behaviors of wind turbines under wind and earthquake excitations

Source: Dynamic behaviors of wind turbines under wind and earthquake excitations: Journal of Renewable and Sustainable Energy: Vol 13, No 4 Source: How Do Wind Turbines Respond to Winds, Ground Motion During Earthquakes? - AIP Publishing LLC A new study investigates the combined effect of wind and earthquake forces to assess the dynamic behavior of wind turbines. The demand for renewable energy is nowadays at its peak. Wind power is a great source of clean energy and is harvested via wind farms placed in numerous regions across the world. This has led to some winds farms being established in earthquake-prone regions making it important to assess the combined excitation under wind and earthquake forces. In the US, these wind farms are most commonly seen in Alaska, Arkansas, California, Idaho, Illinois, Kentucky, Missouri, Montana, Nevada, Oregon, South Carolina, Tennessee, Utah, Washington, and Wyoming. The study, recently published in the Journal of Renewable and Sustainable Energy, aims at establishing a numerical model that will integrates both seismic, wind, and operation forces of wind turbines to evaluate the performance of the wind turbines. This is referred to as the "fully coupled model". Such models have been tested before but the research team emphasizes that a solid interpretation of the results is still missing. The authors studied a 5MW wind turbine subjected to a combination of wind load and input ground motion with the latter being retrieved from a list of earthquake records. The study provides some interesting findings. The results from the sophisticated numerical models suggest that the wind that acts as a dynamic load for the wind turbine also exerts a damping effect on the response of the structure. In particular, when shaking is strong, the energy absorbed due to the aerodynamic damping is higher than the actual wind loading generates hence, the [...]

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 [...]

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 [...]

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 [...]

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

Why Would You Need a Track CPT Rig?

Vertek CPT wants to ensure that you have the right equipment to grow your business. As you are going through the CPT rig purchase process, we’ll have extensive conversations to ensure that we are both on the same page when it comes to where you will be testing, what types of tests you can most easily sell, and which rig or rigs will help you to make the most money. Track Rig Features As you look around our site, you’ll see that some rigs are built on tracks, as opposed to truck beds with wheels. As per with construction equipment, you might expect the tracked equipment to be larger, with CPT rigs the tracked units tend to be smaller. This is because tracked rig CPT platforms are designed to not only traverse and work in difficult terrains, but also to be highly maneuverable around obstacles such as trees, rocks and gulleys. Remember, CPT testing may be specified by your customer for pre-construction activities, meaning that it takes place on a site with little preparation. Having a highly maneuverable platform with low ground pressure can make the difference between you being able to win certain jobs and not. Track rigs are usually designed in order to distribute the weight of the rig over more square inches of contact area. This helps to minimize damage to sensitive areas as well as help the rig not get stuck in less than optimum ground conditions. The overall rig footprints are designed so that the units can be effectively trucked to sites within your service area. Track rigs are designed for deep pushes in tough geologies and the Vertek CPT tracked rigs push from about 10 tons up to 25 tons. With the right combination of weight, ease of maneuverability and set-up features, a tracked [...]

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