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Houston’s Highways, Some of Busiest in Nation, Use Innovative TerraThane Polyurethane Foam Technology to Repair Bad Bridge Approaches, Uneven Joints, and Roadway Depressions.
MOUNTAIRY,NC—Highways around Houston, TX, known as one the nation’s worst cities for traffic behind Los Angeles, D.C., and Atlanta, need constant repair, but can’t be closed while the work is done. Nortex Concrete Lift and Stabilization, Inc., a Ft. Worth, TX company, recently completed a whirlwind repair project on one of the city’s busiest corridors in the NE quadrant where I-10, 610 Loop, I-59, and I-69 feed millions of cars daily to, from, and around Harris County.
Normal groundwater erosion beneath the highways causes the concrete highway slabs to drop, roadway depressions, uneven bridge approaches, and uneven joints that make driving bumpy and uncomfortable, dangerous, and causes severe wear and tear on automobiles.
To make the repairs, the Texas Department of Transportation, TXDOT, brought in Nortex. The company carefully planned out the repairs for the half million pound project, and sent out four crews each with it’s own box truck rig to use a relatively new technology called “foamjacking.” Foamjacking uses high-density polyurethane foam to fill the subterranean voids, and lift the concrete slabs to proper level. “We’ve been lifting and stabilizing roadways with polyurethane foam since we got into the business back in 2003,” says Casey Derosa, asst. gen. mgr. of Nortex. “It’s a far superior method versus the old way of mudjacking.” Mudjacking is a ubiquitous term for a mix of mud, sand, cement, crushed limestone, and water hydraulically pumped into large holes drilled into the concrete slabs to fill voids and level the slabs. Mudjacking uses more and much larger equipment, and requires larger holes to be drilled. It typically requires the roadway to be closed much longer than foamjacking, and takes more time to clean up.
Fugro has completed one of the largest offshore geotechnical investigations in history according to Hydro-International.com. The investigation was performed by two vessels, MV Greatship Manisha and MV Bucentaur (pictured here), for DONG Energy's 1.2 gigawatt Hornsea Project One project which is located 120 km off the UK's Yorkshire coast. The investigation (contract valued at GBP13 million) consisted of 2,800 metres of seabed cone penetration testing and more than 5,000 metres of boreholes over a four month period. [Source: Hydro International. Image: Hydro International]
What will 2015 hold for the tunneling industry? Tunnel Business Magazine asked a panel of 4 industry experts that question. The panel consisted of a Colorado School of Mines Professor as well as reps from Black and Veatch, AECOM, and Kenall Manufacturing. In general they seem to agree that there are opportunities in the US for large combined sewer outfall (CSO) projects, water distribution projects, and even high-speed rail, particularly in California. [Source: Check out all of the analysis at Tunnel Business Magazine]
A team from Northeastern University has a very interesting van used for quantitatively assessing pavement condition using a variety of sensors. They use cameras, laser profilers, accelerometers on axles, pressure sensors in the tires, microphones, and even ground penetrating radar. The researchers reportedly characterized pavement condition of 150 miles of road in 4 days in Beverly, Massachussets, a task that took public employees about 1 year the last time it was performed, in 2010. The cost of the survey was around $25,000. The technology is expected to be commercialized this month. [Source: The Boston Globe. Image: Boston Globe]
Not too much to say about this, but check out the photo. The entire westbound portion of US Highway 52 near the Ohio River was closed last week as a house-sized boulder and other rockfall debris landed on the roadway. Crews anticipated it would take several days to clear the material and reopen the road. [Source: WLWT News via USGS Landslide Events. Image: Kentucky Transportation Cabinet via WLWT]
SALT LAKE CITY, April 13, 2015 /PRNewswire/ -- Boart Longyear (www.BoartLongyear.com), the world's leading provider of integrated drilling services and drilling products, is proud to introduce the LS™250 MiniSonic™, a compact rig suitable for a wide variety of environmental, geotechnical, water and mining projects.
Capable of drilling to depths of up to 250 feet (78m) when used with 4.75 inch (121mm) casing, the wide 600mm rubber tracks provide low ground pressure (.28 bar/4psi) and make it perfect for jobs in the most sensitive and fragile terrains. Plus, its smaller footprint makes it appropriate for projects with small drill pads, environmentally sensitive areas or hard-to-reach sites and requires less support equipment – making it a low-cost solution for a variety of mining, environmental, geotechnical and infrastructure drilling projects.
[Editor] Click through for the rest of the press release from Boart Longyear. [/Editor]
Since March of 2003, the FHWA’s Geotechnical Engineering Circular Number 7 (GEC No. 7) has been the standard reference document for design and construction of soil nail retaining walls in roadway applications, and really in all applications. The FHWA has released an updated version of this manual as of February of 2015. This new version is still called GEC No. 7, but now titled “Soil Nail Walls Reference Manual.” You can download the document from the FHWA’s Geotechnical Engineering website.
I am still in the process of working through the manual, but one of the major changes is the addition of the implementation of the Load and Resistance Factor Design (LRFD) platform. This will have an implication on all future soil nail walls for roadway projects.
The manual also appears to have removed example problems solved using SNAILZ software (by CalTrans) in favor of the FHWA’s own Soil Nail Analysis Program (SNAP) 2 software. I guess we’re going to have to get familiar with that software as well. I’m strongly considering looking into SNAIL Plus by DeepExcav, a commercial product. I’ve seen demos before, and have been very impressed.
Finally, I was very curious to see what they would say about hollow bar soil nails. They review some of the work done in the last 5 years or so done by the FHWA and ADSC. If I understood correctly, it appears that they are saying that because of the uncertainties regarding damage to corrosion protection during installation, they are still not recommending hollow bar nails for roadway applications, except if the ground conditions are non-aggressive and if you use sacrificial steel. I suppose that at least opens the door to this technology for collapsing ground situations.
There was a significant slope failure at the Yeager Airport near Charleston, West Virginia last week. A 2005 project to create an Engineered Material Arresting System (EMAS) at the end of the runway required a massive reinforced soil structure fill slope over 200 feet high since the airport was constructed on top of a hill. According to a presentation published by the geogrid manufacturer, this project was the tallest known geosynthetic reinforced 1:1 fill slope in North America (as of 2010). The slope failure follows a period of significant snow melt and rainfall. It is a deep-seated failure, apparently a compound failure that cuts through the reinforcement based on one of the photos available in the Charleston Daily Mail article cited in the article at the Landslide Blog. I'm sure there will be much more information about this massive failure in the coming months.
National Driller has a nice interview with the 2015 Terzaghi Lecturer, Donald Bruce, President of Geosystems. Bruce, best known for his expertise in grouting, will deliver his Terzaghi Lecture at this week's IFCEE conference in San Antonio. [Source: Read the interview at National Driller. Image: National Driller]
Advanced Construction Technology Services (ACTS) has contracts for geotechnical work for 3 lines of the proposed subway in Doha, Qatar. They have completed investigations for approximately 95 km of line and 51 stations and are currently working on the recommendations for track designers. The contract for the these services is worth approximately $1.37 million. [Source: Trade Arabia. Image: Trade Arabia]
EarthScience Information Systems (ESCIS) is pleased to announce the release of the Shoalhaven City Council Aqua Data website, a branding of the ESdat Public Portal.
Aqua Data is a web-portal providing greatly enhanced community access to the results of water quality monitoring completed by Shoalhaven City Council (SCC). Aqua Data is the public interface of a detailed system designed to streamline the way SCC manage and share environmental data.
Aqua Data is accessed via a link on the Shoalhaven City Council web site directing users to the Aqua Data home page
[Editor]Click through for the rest of the press release and a link to go check out the Aqua Data interface! [/Editor]
WSDOT reported that Bertha has slowly began moving again. It must tunnel through 20 feet of unreinforced concrete with its broken seal to break through into the rescue shaft. Once that happens, the repairs to her cutterhead can commence. The Seattle Tunnel Partners predict Bertha will overheat, as she did before stopping for repairs. If that occurs, they will stop tunneling to wait for the machine to cool before continuing. STP crews also chipped away at a Bertha-sized cut-out in the access shaft to make for a cleaner breakthrough. See video below. [Source: WSDOT and WSDOT YouTube Channel. Image: YouTube]