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Cyclic triaxial tests: Evaluation of liquefaction resistance in chemically treated soils

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Cyclic triaxial tests: Evaluation of liquefaction resistance in chemically treated soils


Researchers explore the potential of stress-controlled and strain-controlled cyclic triaxial testing for liquefaction resistance evaluation of chemically treated soils. Credit: Professor Shinya Inazumi , Shibaura Institute of Technology, Japan. www.sciencedirect.com/science/article/pii/S259012302502938X?via%3Dihub

Soil liquefaction can be a major threat to the infrastructure and built environments in an earthquake-prone area. This happens due to substantial loss of soil stiffness and strength due to applied stress. Loose, moderately granulated, sandy soil is more prone to soil liquefaction.

Recognizing the urgent need to enhance urban resilience in seismic-prone regions, particularly in rapidly urbanizing areas vulnerable to such hazards, scientists are focusing on different mitigation techniques. Soil compaction technique is one of the effective methods developed to enhance the liquefaction resistance of the soil.

However, developing a proper evaluation method is also of the utmost importance. Traditionally, stress-controlled cyclic triaxial tests are done for the evaluation. However, the results are often inconsistent and this can lead to an overestimation of the resistance capacity.

Also, focusing on sustainable options is an inevitability in present times. So, the scientists are also trying to focus on formulating and testing environment-friendly grouting substances.

To bridge the methodological gaps and promote safer, eco-friendly ground improvement for the global infrastructure, Professor Shinya Inazumi from College of Engineering, Shibaura Institute of Technology (SIT), Japan, along with a small team of researchers, developed a strain-controlled testing method using cyclic triaxial.

“We pursued this research after recognizing the urgent need to improve urban resilience to earthquakes,” mentions Prof. Inazumi, talking about the motivation for the study. The findings were published in the journal Results in Engineering.

As a grouting solution, an environment-friendly formulation of colloidal silica (CS) and geothermal-recycled sodium silicate were used. Compared to conventional grouting solutions, this reduces carbon-dioxide emissions during production by approximately 60%. Three different concentrations of CS–6%, 8%, and 10% were tested.

The stress-controlled test was conducted following previously established protocol. For the strain-controlled cyclic triaxial test, double-amplitude axial strain was maintained constant at 5%, simulating large cyclic deformations from earthquakes. Cumulative dissipated energy was evaluated as an alternative indicator of liquefaction potential.

The phase transformation angle was evaluated. Cumulative dissipated energy as a unified evaluation index was also evaluated. Pore pressure-based criterion, strain-based criterion, and energy-based criterion were assessed to evaluate the resistance.

The test result revealed that a higher concentration of CS increases the resistance, with 10% concentration yielding the best result. Analysis of the cumulative dissipated energy confirmed that energy-based evaluation is a viable approach for assessing liquefaction resistance.

“This new method is superior to the present evaluation methods,” mentions Prof. Inazumi. “It reduces the need for multiple specimens, which makes it cost-effective and produces consistent, reproducible results.”

The team also observed a linear relationship between dissipated energy and liquefaction resistance ratio (RL20, 5%) which can be a potential calibration path for integrating strain-controlled results into existing stress-based design charts. This can save time and improve previous test results significantly.

The new method’s potential of being integrated into energy-based designs supports its use in performance-based seismic design frameworks, as proposed in recent studies.

“The research has profound real-world applications, especially in earthquake-prone regions,” says Prof. Inazumi.

“One key application is retrofitting existing structures, based on the updated test results. Chemical grouting with CS can be used to mitigate liquefaction hazards in waterfront projects, such as expanding school buildings, residential complexes, and medical facilities near seawalls.”

Furthermore, this method can stabilize loose sands against lateral spreading. The eco-friendly nature of the silica formulation can also ensure the safety of marine environments. Additionally, owing to the low-vibration nature of this method, it could be ideal for crowded urban areas, aiding in the development of bridges, ports, and dams in regions such as Japan and California.

Taken together, integrating this new method of testing into global standards could save lives, minimize economic losses by providing precise, cost-effective liquefaction mitigating strategies.

In the future, the testing method could be used to evaluate other types of soil, other grout types, and testing methods. The study hugely contributes to the development of performance-oriented ground improvement design under seismic loading conditions.

More information:
Khin Nyein Chan Kyaw et al, Evaluation of liquefaction resistance in chemically grouted sand using cyclic triaxial tests, Results in Engineering (2025). DOI: 10.1016/j.rineng.2025.106875

Citation:
Cyclic triaxial tests: Evaluation of liquefaction resistance in chemically treated soils (2025, September 12)
retrieved 12 September 2025
from https://techxplore.com/news/2025-09-cyclic-triaxial-liquefaction-resistance-chemically.html

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Papa Johns Is Getting Into Drone Delivery—but Not for Pizza

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Papa Johns Is Getting Into Drone Delivery—but Not for Pizza


Starting today, eager customers of the US pizza restaurant chain Papa Johns living in one corner of southern North Carolina will have the opportunity to receive their food from the sky, thanks to a new collaboration with Alphabet’s drone company, Wing. But Papa Johns’ signature pizzas won’t be on offer. Instead, drone-loving North Carolinians will have to choose between three kinds of sandwiches, a newer product for the fast-food chain: Philly cheesesteak, chicken bacon ranch, or steak and mushroom varieties.

Drone deliveries are popping up in more communities across the US and the world. Questions about the long-term economics and regulatory picture around unmanned aerial vehicles persist, but Wing boasts partnerships with Walmart, Panera, and DoorDash and is delivering through the sky to customers in four metro areas: Atlanta, Charlotte, Dallas-Fort Worth, and Houston. (In 2019, Wing received the US Federal Aviation Administration’s first certificate allowing a drone delivery company to operate in the country.) Competing drone companies, including Zipline, Amazon Prime Air, and Flytrex, fly packages, medical supplies, and Chipotle burritos in select communities across countries like Ghana, Japan, and the US.

But until very recently, drone operators have struggled to fly full-size pizzas. For companies hoping to break into the food delivery space, this is unfortunate: 11 percent of the US population eats a slice on any given day, according to the US Department of Agriculture. In a fast-diversifying restaurant industry, getting them to customers is still big business. But the realities of physics, engineering, and the restaurant business conspire to make pizzas a challenge for drones.

Flying Pizzas

Traditionally, pizza is the experimental tech delivery of choice. The familiar and cheap cheese-sauce-bread combo has been loaded onto self-driving cars and autonomous sidewalk delivery vehicles and has been assembled by robots. It’s a fast and satisfying option, especially for busy families tight on time. And theoretically, a great fit for automated drones, among one of the faster delivery options—people love fresh, piping-hot pizza.

But transporting one by drone requires some extra work, says Wing CEO Adam Woodworth. “Pizza comes in a very different box, with a big, flat surface area,” he says. They’re not naturally aerodynamic. Also, “you don’t want a pizza tilted.”

Wing’s relatively lightweight drones are engineered to carry three specific package sizes; right now, pizza boxes aren’t one of them. Woodworth says a new design is on the horizon. “I want to see pizzas coming at me from the sky,” he says.

Flytrex, an Israel-based drone delivery company, announced late last month that it had finally solved the problem. In collaboration with rival pizza chain Little Caesars, the company began delivering via drone up to two large pizzas (16 inches each), plus sodas and bread, in Wylie, Texas, a suburb of Dallas. The leap comes courtesy of a much bigger new drone, capable of carrying up to 8.8 pounds for four miles.

Courtesy of Flytrex



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Chevron Wants a School District Tax Break for a Data Center Power Plant in Texas

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Chevron Wants a School District Tax Break for a Data Center Power Plant in Texas


A major oil company is seeking a state tax break in Texas worth hundreds of millions of dollars to build a massive power plant. The energy won’t be going to residential customers, though. Instead, the gas plant will be used to power a data center whose eventual tenant could be Microsoft.

Chevron subsidiary Energy Forge One has filed an application with the State Comptroller’s board to obtain a tax abatement for a power plant it’s building in West Texas. In late January, the comptroller’s office made a recommendation to support the application’s approval—the first such approval under the program for a power plant intended solely for data center use.

In March, following news reports that Microsoft was looking into purchasing power from the Energy Forge project, Chevron said that it had entered into an “exclusivity agreement” with Microsoft and Engine 1, an investment fund involved in the project. In January, Microsoft pledged to be a “good neighbor” in communities where it is building data centers, including promising to pay a “full and fair share of local property taxes.”

The potential tax abatement for the project comes as big tech companies are battling rising public fury about data centers and electricity costs. It also comes as lawmakers start to cast a more critical eye on ballooning incentives for data centers, some of which have cost some states—including Texas—$1 billion or more each year.

Chevron spokesperson Paula Beasley told WIRED in an email that all tax incentives under consideration for the Energy Forge project “apply solely to the power generation facility” to “support new energy infrastructure, and do not extend to any future data center facilities that may be served.” Beasley also said that there is currently “no definitive agreement” with Microsoft for this power plant.

“Microsoft is in discussions with Chevron,” Rima Alaily, Microsoft’s corporate vice president and general counsel for infrastructure, said in a statement to WIRED. “No commercial terms have been finalized, and there is no definitive agreement at this time.”

Chevron is applying for a tax abatement for the project under Texas’ Jobs, Energy, Technology, and Innovation (JETI) Act. Passed in 2023, the program is intended to incentivize businesses to build large infrastructure projects in the state in exchange for guarantees to bring jobs and revenue. Accepted projects get a cap set on the amount of taxable property they can be charged through local school district taxes.

The Pecos-Barstow-Toyah school board approved the project’s application at a meeting in February. The state pays for the tax abatement, so the school district itself does not lose out on any money.

According to documents from the state, the Chevron project could net more than $227 million in savings for the company over a 10-year period, depending on the eventual size of the project and investment. The application says the plant will provide “over 25 permanent, full-time jobs,” though there’s no requirement to do so because it’s considered an electricity generation facility.

The planned gas plant won’t connect to the grid, instead providing “electricity for direct consumption by a data center,” according to its application. So-called behind-the-meter gas plants have become increasingly popular for data center developers facing yearslong waits to connect to the grid. According to data from nonprofit Global Energy Monitor, the US at the start of the year had nearly 100 gigawatts of gas-fired power in the development pipeline solely to power data centers, with several more massive gas projects announced since the data was published.

A WIRED analysis of less than a dozen power plants being constructed to explicitly serve data centers, including the Chevron project, found that these power plants are permitted to emit more greenhouse gases than many small- to medium-size countries. The Energy Forge plant alone could emit more than 11.5 million tons of CO2 equivalent annually—more than the country of Jamaica emitted in 2024. Beasley told WIRED that the plant “is being designed to comply with applicable environmental regulations, including all applicable federal and state air quality standards.”



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CUDA Proves Nvidia Is a Software Company

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CUDA Proves Nvidia Is a Software Company


Forgive me for starting with a cliché, a piece of finance jargon that has recently slipped into the tech lexicon, but I’m afraid I must talk about “moats.” Popularized decades ago by Warren Buffett to refer to a company’s competitive advantage, the word found its way into Silicon Valley pitch decks when a memo purportedly leaked from Google, titled “We Have No Moat, and Neither Does OpenAI,” fretted that open-source AI would pillage Big Tech’s castle.

A few years on, the castle walls remain safe. Apart from a brief bout of panic when DeepSeek first appeared, open-source AI models have not vastly outperformed proprietary models. Still, none of the frontier labs—OpenAI, Anthropic, Google—has a moat to speak of.

The company that does have a moat is Nvidia. CEO Jensen Huang has called it his most precious “treasure.” It is not, as you might assume for a chip company, a piece of hardware. It’s something called CUDA. What sounds like a chemical compound banned by the FDA may be the one true moat in AI.

CUDA technically stands for Compute Unified Device Architecture, but much like laser or scuba, no one bothers to expand the acronym; we just say “KOO-duh.” So what is this all-important treasure good for? If forced to give a one-word answer: parallelization.

Here’s a simple example. Let’s say we task a machine with filling out a 9×9 multiplication table. Using a computer with a single core, all 81 operations are executed dutifully one by one. But a GPU with nine cores can assign tasks so that each core takes a different column—one from 1×1 to 1×9, another from 2×1 to 2×9, and so on—for a ninefold speed gain. Modern GPUs can be even cleverer. For example, if programmed to recognize commutativity—7×9 = 9×7—they can avoid duplicate work, reducing 81 operations to 45, nearly halving the workload. When a single training run costs a hundred million dollars, every optimization counts.

Nvidia’s GPUs were originally built to render graphics for video games. In the early 2000s, a Stanford PhD student named Ian Buck, who first got into GPUs as a gamer, realized their architecture could be repurposed for general high-performance computing. He created a programming language called Brook, was hired by Nvidia, and, with John Nickolls, led the development of CUDA. If AI ushers in the age of a permanent white-collar underclass and autonomous weapons, just know that it would all be because someone somewhere playing Doom thought a demon’s scrotum should jiggle at 60 frames per second.

CUDA is not a programming language in itself but a “platform.” I use that weasel word because, not unlike how The New York Times is a newspaper that’s also a gaming company, CUDA has, over the years, become a nested bundle of software libraries for AI. Each function shaves nanoseconds off single mathematical operations—added up, they make GPUs, in industry parlance, go brrr.

A modern graphics card is not just a circuit board crammed with chips and memory and fans. It’s an elaborate confection of cache hierarchies and specialized units called “tensor cores” and “streaming multiprocessors.” In that sense, what chip companies sell is like a professional kitchen, and more cores are akin to more grilling stations. But even a kitchen with 30 grilling stations won’t run any faster without a capable head chef deftly assigning tasks—as CUDA does for GPU cores.

To extend the metaphor, hand-tuned CUDA libraries optimized for one matrix operation are the equivalent of kitchen tools designed for a single job and nothing more—a cherry pitter, a shrimp deveiner—which are indulgences for home cooks but not if you have 10,000 shrimp guts to yank out. Which brings us back to DeepSeek. Its engineers went below this already deep layer of abstraction to work directly in PTX, a kind of assembly language for Nvidia GPUs. Let’s say the task is peeling garlic. An unoptimized GPU would go: “Peel the skin with your fingernails.” CUDA can instruct: “Smash the clove with the flat of a knife.” PTX lets you dictate every sub-instruction: “Lift the blade 2.35 inches above the cutting board, make it parallel to the clove’s equator, and strike downward with your palm at a force of 36.2 newtons.”



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