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Crews trying to learn extent of Wanapum Dam crack

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Crux is providing challenging access exploratory drilling services at the Wanapum Dam in central Washington.  A crack was discovered on February 27, 2014 and the geotechnical exploration program is intended to provide more information regarding the extent of this crack.  Six borings have been completed to-date, and Crux crews expect to drill a minimum of twenty by the conclusion of the project.

Click here to view the story on KREM.com

 

Exploration drilling started at proposed dam site

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Crux crews are onsite near Whiteriver, AZ to complete core drilling and sampling at the proposed Miner Flat dam site. Thirteen angled core holes and a total of approximately 3,365 feet of drilling will be completed. Access to borings is being achieved through a combination of track vehicle and helicopter, and core recovery in the area has proven challenging in the past. All operations are taking place on White Mountain Apache Tribe lands and require close coordination with tribal representatives.

Geotechnical Exploration Drilling

If constructed, the dam will cross the north fork of the White River, measuring approximately 160 feet high and with a crest length of approximately 450 feet. The proposed project, including the dam, as well as a storage reservoir, a pumping plant, treatment facilities, and a distribution system, would provide long-term water stability and reliability to the Fort Apache Indian Reservation.

Crux is performing permeability testing throughout drilling operations and Vibrating Wire Piezometers will be installed in eight of the thirteen borings. Downhole imaging will be completed in select borings by Crux Oriented Borehole Logging (COBL). Drilling operations commenced on March 7, 2014 and Crux expects to be onsite until June 2014.  Continue reading →

Company Profile Featured in Piling Canada Magazine

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Piling CanadaA History of Problem Solving 

When Crux first began installing micropiles in 2002, the company was already known for providing difficult-access geotechnical exploration services throughout the western United States for tunnel, dam, highway and slope stabilization projects, including the Hoover Dam Bypass.  Crux initially utilized micropiles for structure foundation support and slope stabilization before adapting the technology as a foundation alternative in the electrical transmission market. Micropiles provide the ability to install a high capacity deep foundation system in remote or environmentally sensitive locations, explained Tunison, Crux’s Vice President of Operations.

“Micropiles are replacement piles constructed using high-strength grout and steel, and can be installed using lightweight equipment,” he explained.

In 2004, Crux began construction on the 57-mile-long Swan Lake-Lake Tyee Intertie between two hydroelectric projects in Southeast Alaska.  This was the first project of its magnitude to use helicopter-supported micropile foundations exclusively for its whole alignment, relying on Crux’s customized drills, skilled helicopter support, and specially trained drillers.

View Full Article →

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Micropiles Installed in New Jersey Wetland

Micropiles installed in new jersey wetland

Crux recently provided micropile foundation EPC services within a Priority Wetland for Public Service Electric & Gas Company’s (PSE&G) Susquehanna-Roseland Electric Reliability Project.  The specialty deep foundation was selected to accommodate challenging subsurface conditions and access constraints associated with the protected area.

The full alignment will span from Berwick, Pa. to Roseland, N.J., with a 1.5-mile segment traversing the Troy Meadows area in Morris County, New Jersey.  Micropile foundations were selected for all seven steel pole structures within the wetland due to standing water and other permit access restrictions.  Prime contractor KH&M (a joint venture between Kiewit and Henkles & McCoy) was permitted to mat a roadway to one structure, but the remaining six required helicopter support for materials and equipment.  Micropiles are lightweight elements and can be installed using lightweight equipment, making them conducive to these types of restrictions.

In order to minimize impacts to the wetland and facilitate construction activities, a unique closed cell cofferdam was employed at each structure site.  This setup provided a stable platform for equipment in soft soils and groundwater, contained drill spoils from entering the wetland, and acted as a form for concrete placement.  A rotating drill carriage and micropile drill were set on top of the cofferdam to install micropiles in a battered array.  Micropiles proved to be an efficient choice to bridge through extremely soft soils and reach underlying bedrock, which varied in depth between 60 feet to 115 feet below ground level.

Continue reading →

Northwest Transmission Line: Powering Growth

Building & Construction Canada: Powering Growth
Affiliated publications Building & Construction Canada and Energy & Infrastructure Magazine feature an article in their Winter 2013 issues on the construction of the Northwest Transmission Line (NTL).  The article, titled “Powering Growth,” discusses various challenges associated with construction of the alignment, located in Northern British Columbia.

Valard Construction, a Quanta Services company, teamed with Burns & McDonnell to lead the 214-mile EPC project.  Crux worked with Valard to provide design-build foundation services for seven lattice tower structures on the alignment located in particularly challenging terrain.  Once completed, the NTL will connect remote areas of the province to the grid and pave the way for potential industrial developments.

 

Read the full article to learn more about the NTL and see the Vendor Focus column on page 24 for information regarding Crux’s alternative foundation work.

 

Photo Gallery: Micropiles as a Foundation Alternative

As a followup to the Burns & McDonnell sponsored Advanced Technologies Webinar Series, Transmission & Distribution World is featuring related photo galleries on their website.  Visit the Micropiles as a Foundation Alternative gallery to view project photos where micropiles were utilized to solve a number of challenges, including access restrictions, environmental regulations, low overhead clearance and challenging subsurface conditions.

Transmission & Distribution World

North American Tunnelling Journal: Ahead of the Game

“Specialty contractors are in agreement that a general trend is towards more acceptance and earlier adoption of pre-excavation grouting.” 

With a number of complex tunneling projects in the works, several dealing with challenging ground conditions, the use of pre-excavation grouting techniques is increasing.  In the September 2013 issue of North American Tunnelling Journal, Crux Subsurface, Malcolm Drilling, Moretrench and Hayward Baker provide a detailed look at the types and benefits of these techniques in the industry.

Specialty Grouting

Read the Article →

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Crux begins work on BC Hydro project

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Northwest Transmission Line

Crux has mobilized to British Columbia, Canada, to provide specialty foundation services on BC Hydro’s Northwest Transmission Line (NTL). The company has been awarded design-build micropile foundation work for seven lattice tower structures on the new 214-mile (344 km) alignment. Crux will be working as a subcontractor to Valard Construction, the general contractor for the NTL. Once completed, the line will connect the Skeena Substation near Terrace, B.C., with a new substation near Bob Quinn Lake.

Crux has significant experience providing specialty foundation design and construction throughout the United States, but this will mark the first Canadian transmission project for the company.

“The logistics of transmission line construction are so similar between Canada and the United States that it was a natural transition for us,” says Crux President, Nick Salisbury. “Some of the structures on the NTL alignment are located in challenging terrain and hard rock, and we believe that micropile foundations provide the best solution to construction challenges in these areas.”

Continue reading →

Join Crux on July 17 For A Live Webinar Presentation!

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As part of the Advanced Technologies Webinar Series, Crux President Nick Salisbury will present the applications and benefits of utilizing micropile foundations in the transmission industry.

Webinar - Micropiles: A Foundation Alternative for Challenging Conditions

To register, visit: http://www.burnsmcd.com/Services/Detail/Advanced-Technology-Series

Busy on the 17th?  The recorded webinar will be available in the Burns & McDonnell archives approximately two weeks after the live webinar date.

 

U.S. 89 Landslide Exploration

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Crux recently concluded an exploration drilling program at a landslide site near Page, Ariz.  The slide occurred on Feb. 20, 2013, causing more than 150 feet of roadway to buckle and temporarily closing a portion of U.S. 89.

Contracted by Kleinfelder, Crux provided emergency core drilling and instrumentation services on the project to locate precisely where the landslide occurred, determine if it was still moving and establish the general stability of the slope.  Seventeen core holes were drilled to depths of between 29 and 250 feet.  The damage to the roadway created access challenges, requiring a combination of track mounted drill rigs and helicopter support.

 

Continue reading →

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