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 [...]

Why the Himalayas are crumbling

Source: On a precipice: Why the Himalayas are crumbling The landslides were inevitable, Sunni Ram keeps saying. His village, Thatch, is located right above a highway near Nigulsari village of Kinnaur district, where a massive landslide on August 11 killed 28 people; another 13 were injured. A month ago, another landslide in this district in Himachal Pradesh had killed nine tourists and damaged a bridge. While the incidents have made the headlines due to the high casualties, Ram says, this is not the first time landslides have occurred at these places. “Another landslide near Thatch in 2019 killed three dozen sheep and goats,” he adds. Rockfalls have also become frequent in the last few years. It’s as if the Himalaya is crumbling from these spots, says Ram. A team from the Geological Survey of India, following their visit to Nigulsari, has said in its report that a steeply inclined slope and incessant rainfall are behind the incident. Ram and several other residents of Thatch and Nigulsari, however, blame it on the 1,500 MW Nathpa Jhakri Power Project on the Sutlej. The project has a 27.4 km long headrace tunnel for conveying water to the underground power station. This tunnel, dubbed one of the longest in the world, passes under Nigulsari and Thatch and is not far away from the spot where the landslide occurred. “The effects of the heavy explosions made during the construction of the tunnel in the late 1990s are becoming visible now,” says Govind Moyan, deputy head of Nigulsari gram panchayat. All the five villages under this panchayat, including Nigulsari and Thatch, are affected in some or the other way by the Nathpa Jhakri project. Almost every house has cracks on its walls along with fissures in the fields and gardens. Springs too have dried up, says [...]

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 [...]

Mitigating carbon may have unintended consequences

Source: Mitigating carbon may have unintended consequences | Penn State University UNIVERSITY PARK, Pa. — Controlling carbon release into the atmosphere will reduce carbon dioxide and slow global warming, but could there be unintended consequences for human health? Now, thanks to a three-year grant of about $400,000 from the National Science Foundation, researchers at Penn State will investigate potential positives and negatives of decarbonization. "There can be unintended health co-harms from some carbon mitigation strategies," said Wei Peng, assistant professor of international affairs and civil and environmental engineering and principal investigator on the project. "For instance, large-scale bioenergy production may drive up food prices, which leads to nutrition-related health co-harms." Of course, mitigating carbon can also bring health benefits, including a reduction of pollution in the atmosphere. "Tangible human health co-benefits can motivate stronger support for climate policy," said Peng. The researchers aim to improve understanding of what factors determine the size and scope of health outcomes from decarbonization and to identify strategies most likely to yield overall health benefits. Focusing on the U.S., Peng and her team will develop a framework integrating energy, food and health. They will improve health variables in a state-level integrated assessment model and connect it to a fine-resolution, health impact assessment model. They will also develop a large number of scenarios of decarbonization to encompass future uncertainties, technology and markets. This project is the extension of two seed grants from Penn State's Institutes of Energy and the Environment and Institute for Computational and Data Sciences. Vivek Srikrishnan, assistant professor of biological and environmental engineering, Cornell University, is the co-principal investigator (PI) on this project. Peng is also a co-PI on a project looking to model the interactions of climate change, air quality and social inequalities. This five-year, $1.5 million NSF grant, co-led by Mark [...]

Himalayan hydropower ‘clean but risky,’ warn scientists

Source: Himalayan hydropower 'clean but risky,' warn scientists With its steep topography and abundant water resources the Himalayas offer sustainable, low-carbon hydropower for energy-hungry South Asia. But there is a catch—the mountain range falls in one of the world's most seismically active regions. A group of 60 top Indian scientists and environmentalists wrote an open letter to Prime Minister Narendra Modi earlier this month seeking his intervention in stopping "any more hydroelectric projects in the Himalayas and on the Ganga whether under construction, new or proposed." The letter cites the Intergovernmental Panel on Climate Change's sixth assessment report which says that the Himalayas have been affected by warming. The report warns that "rising temperature and precipitation can increase the occurrence of glacial lake outburst floods and landslides over moraine-dammed lakes" in high mountain Asia. Moraine consists of rocks and soil left behind by moving glaciers. Hydropower, the world's largest source of renewable electric power with1,308 gigawatts of installed capacity in 2019, is expected to play a critical role in decarbonizing power systems, according to the International Energy Agency (IEA), an inter-governmental body. Stretching 2,400 kilometers in an arc that includes the world's highest peaks, the Everest in Nepal and K2 in Pakistan, the Himalayas rank high among global hot spots for developing hydropower, though only 20 percent of the estimated 500 gigawatt potential has been tapped so far. But that situation is rapidly changing with hydropower projects mushrooming along the Himalayan arc—which covers territory in Bhutan, China, India, Nepal and Pakistan—despite proven risks from quakes, landslides and glacial lake outburst floods. The immediate trigger for the appeal to Modi was a decision by India's Ministry of Environment, Forest and Climate Change to allow the restarting of seven controversial hydropower projects in the Himalayan state of Uttarakhand. Three of these projects—Tapovan-Vishnugad (520 [...]

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 [...]

Construction Vibrations

Source: Construction Vibrations -NEW (7004IW2022) INSTRUCTOR:  Antonios Vytiniotis, Ph.D., P.E Participants will have access to the virtual workshop video archives and materials for 60 days from the start day of the workshop. Virtual Workshop Brief The workshop will cover a variety of issues regarding construction vibrations. It will start by describing the sources of construction vibrations, the propagation of vibrations with a soil and scatter effects. Then it will cover the effects of such vibrations in: 1) structures; 2) human perception; and 3) indirect effects of such vibrations. The workshop will cover examples of construction vibration effects in various structures and will show how conditions in structures can be evaluated to understand whether they are caused by vibrations. The workshop will show how construction vibrations can be monitored effectively by state-of-the-art equipment. Finally, this workshop will show how to analyze the data from monitoring to generate valuable insights about their effects on structures. A greater understanding of construction vibrations will help in mitigation of their damaging effects. Benefits and Learning Outcomes Upon completion of this course, you will be able to: Explain sources of construction vibrations Explain effects of construction vibrations Explain causation of damage potentially associated with construction vibrations Monitor construction vibrations Mitigate construction vibrations Avoid costly adjacent construction litigation Assessment of Learning Outcomes Achievement of the learning outcomes by attendees will be assessed through online discussion and case studies. A short post-assessment (true-false, multiple choice and fill in the blank questions) will also be administered. Who Should Attend Geotechnical Engineers Structural Engineers Civil Design Engineers Owners Construction City Planners Workshop Outline Day 1 Construction Vibration Sources Vibration Propagation and Energy Dissipation Discussion about Literature Data Interactive discussion and quiz about sources, propagation and state of the practice Human Perception of Vibrations Direct Effects of Vibrations Interactive discussion about effects [...]

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 [...]

ASU Receives Western States Seismic Policy Council Award in Excellence

Source: Sustaining solid ground | ASU News   A team of faculty members and students in the Ira A. Fulton Schools of Engineering at Arizona State University contributed to a major geotechnical engineering field research project recently recognized with a 2021 Western States Seismic Policy Council Award in Excellence. Associate Professor Leon van Paassen led the group from ASU’s Center for Bio-mediated and Bio-inspired Geotechnics, in a collaboration with researchers from Portland State University and the University of Texas at Austin. The endeavor has been funded by the Natural Hazard Engineering Research Infrastructure program of the National Science Foundation. Recent ASU civil engineering doctoral graduate Elizabeth Stallings Young (second from the right) is shown with Portland State University students and staff members involved in characterizing soils near the Portland International Airport, one of two main sites for a major soil liquefaction research project supported by the National Science Foundation. Van Paassen and Professor Edward Kavazanjian, director of the Center for Bio-mediated and Bio-inspired Geotechnics, have collaborated on projects to reduce the impact of earthquakes on soils. One of these aftereffects is liquefication, or the process by which soil saturated with water loses strength, which can lead to ground failure. ​The multi-university project involves microbially induced desaturation — called the MID technique — for mitigation of earthquake-induced liquefaction in silty soils. Photo by Leon van Paassen/ASUDownload Full Image Seeking earthquake and engineering solutions The work has included treating two test sections located within the Port of Portland Critical Energy Infrastructure hub (the Harborton site) and adjacent to Portland International Airport (the Sunderland site). The map shows two sites in the vicinity of Portland International Airport and the Port of Portland Critical Energy Infrastructure hub that are test sections for the research to develop techniques for reducing soil damage as a result of earthquakes. Map courtesy of Portland State University There, researchers monitored the treatment performance and [...]

Earthquake in Haiti Triggers Landslides

Source: Hundreds of landslides followed Haiti earthquake, Tropical Depression Grace - The Washington Post Source: Earthquake in Haiti Triggers Landslides After a 7.2 magnitude earthquake hit southwestern Haiti on the Saturday morning of August 14th, hundreds of landslides threatened the area. Landslides are one of the biggest causes of earthquake-related deaths. In 2010, the earthquake near Haiti's capital, Port-au-Prince, killed roughly 200,000 people and led to tens of thousands of landslides. The earthquake was centered about eight miles southeast of Petit-Trou-de-Nippes at a depth of six miles. USGS reported at least 150 landslides south of the epicenter, to the west of the town L'Asile. The mountains and south of Beaumont experienced hundreds more. “Even though a lot of the central and western parts of the epicentral area have been obscured by cloud cover, we haven’t seen too many landslides in the gaps in the clouds,” wrote Robert Emberson, a landslide researcher at NASA’s Goddard Space Flight Center. “We anticipate that the bulk of the landsliding (at least from the earthquake) is in the [Pic Macaya] National Park.” The National Hurricane Center predicted 5 to 10 inches of rain in Haiti with a possibility of up to 15 inches. Flash flooding, mudslides, and landslides were all expected following the rain. “With the ongoing tropical storm rainfall, further landslides are likely,” wrote Emberson. “In particular, landslide material mobilized by the earthquake may be washed downstream as debris flows. We will continue to monitor changes over the coming days to assess the exacerbated impact of the rainfall and provide situational awareness.” Landslides and earthquakes have recently in multiple parts of the world. Denali Park, Sichuan China, Battle Creek Michigan, and a recent Monsoon in India are just four of the most recently affected areas.

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