GeoPrac.net is a community of practitioners of geotechnical engineering, geological engineering, engineering geology, geophysics, hydrogeology and related disciplines. We offer members and visitors the foremost collection of geo-related articles, news, and online resources to keep those geo-professionals in practice at the forefront of their respective fields.
The landmark City of Venice, Italy is known for it's world famous canals, architecture and for some...its flooding. Part of the problem has been blamed on ground subsidence from pumping of shallow ground water in the mid 1900's. A massive project dubbed MOSE has been in progress for some time to build inflatable gates to stop high tides from flooding the Venice lagoon.
A recent paper in the Journal Water Resources Research evaluates the possibility of injecting water into the formations to stop and perhaps even reverse the subsidence. The article from Ars Technica (link below) mentions that the technique was used with some success in the Long Beach, California area. The study authors had no boreholes in the area, but were able to rely on a large volume of high-quality seismic data obtained by the Italian Government from oil companies. Their simulations involved 15 boreholes around the City of Venice pumping seawater continuously for 10 years. At that point, they authors concluded there is the potential to lift the city 25-30 cm. [Source: Ars technica via Geoengineer.org. Image: De Saye / Rapho via arlindo-correia.com]
Crux Subsurface, Inc. of Spokane, WA was recently awarded a contract by San Diego Gas and Electric to provide design and installation of micropile foundations at 16 tower locations along a 7 mile stretch of power line for a wood to steel replacement project. Crux is best known for their difficult access and extreme access geotechnical construction and geotechnical investigation work, including helicopter access in rugged terrain which seems to be the case on this project. The work is scheduled to begin this month. [Source: National Driller. Image: National Driller]
Foamed concrete has been used in geotechnical applications as lightweight backfill material in applications where reduction of vertical or lateral loads was critical. In this application, the foamed concrete is designed to 'fail' when an aircraft overruns the regular runway. The foamed concrete Engineered Materials Arresting System or EMAS stops the aircraft without causing catastrophic damage. According to the article, there are about 30 runway overrun accidents each year involving commercial aircraft, and there have been about 1,000 deaths from these types of accidents since 1995. [Source: Gizmodo via ASCE SmartBrief. Image: Gizmodo]
In this 2007 ENR article, a drilling superindtendent from Case Foundation, Rob Jones, is profiled while his company works on the foundations for a Chicago highrise. As a geotechnical engineer who designs drilled shaft foundations, I found it very interesting to learn more about the guys on the construction end of drilled shafts. There is no question in my mind that those guys work a lot harder than I do. [Source: ACE Mentor Program. Image: ENR]
A steel sheet pile cofferdam has been built around the HMS Alliance, a British submarine launched in 1945. The cofferdam will be infilled to create a safe place to perform restoration work. [Source: New Civil Engineer. Image: NCE]
December 8th 2011 5:00 PM - American Piledriving Equipment's 8-hammer “Octakong” vibratory pile driver hammer drove the final record breaking pile in front of a crowd of over 200 people on the South China Sea, who came to witness the world's largest pile drive to grade. The last of 120, 72’ diameter steel piles has been driven into place, completing construction of two circular sea bound walls in the South China Sea, for the Hong Kong-Zhuhai-Macau Seaway project.
[Editor] Click through for the rest of the press release and an installation video. [/Editor]
Scott Deaton is the President of GeoPrac sponsor Dataforensics that specializes in data collection for geotechnical engineering, materials testing and environmental engineering. This video was created by Terracon as part of their Green Light series on "What's Driving Innovation in Transportation".
Young geotechnical engineers and geoengineering professionals in the first 5 years of their careers may be elligible for a $500 grant to attend the 2012 Geo-Congress conference in Oakland, California March 25-29. See the Geo-Institute link below for more information. Applications are due by February 25, 2012. [Source: Geo-Institute]
This article gives a nice, and balanced overview of the hydraulic fracturing or fracking process used to fracture rock and extract oil and gas from a formation that you could not produce from otherwise. 90 percent of oil and gas wells in Colorado are fracked according to the article. And most fracking is done in a safe and responsible way using sound technology and practices. According to Matt Watson, an energy policy specialist with the Environmental Defense Fund in Washington D.C.:
The biggest pollution problems have been caused by surface spills, abandoned wells and poorly constructed wells, which allow gas, oil and chemicals to escape...
There is also a nice graphic showing the composition of fracking fluid, the source of much concern in the media and with environmental groups. The fluid is 99.4% water and sand (91.1% water and 8.3% sand). The remaining 0.6% does have some chemicals in it, but it hardly sounds like the toxic fluid that it is commonly portrayed as. The used fluids can be a potential hazard, but in Colorado, 68% of wells have a closed system where the fluid is pumped back to closed tanks and much of it is re-used. [Source: The Denver Post via The RockWare Blog. Image: Denver Post - RJ Sangosti]
Happy New Year! Here are a list of updated and new ASTM standards related to geotechnical engineering, materials testing and other subjects of interest to geoprofessionals. In this batch is a new standard for testing individual geogrid junction strength and other updated standards for geogrid testing. The standard for geofoam has been updated, so has the standard for SPT sampling. Read on for a list of these updated standards and others.
Happy New Year! Here are a list of updated and new ASTM standards related to geotechnical engineering, materials testing and other subjects of interest to geoprofessionals. In this batch is a new standard for testing individual geogrid junction strength and other updated standards for geogrid testing. The standard for geofoam has been updated, so has the standard for SPT sampling. Read on for a list of these updated standards and others.