The girders of an old bridge traveled for more than 50 years by visitors to and from the Outer Banks of North Carolina could help improve future bridge construction.

The Herbert C. Bonner Bridge was dismantled beginning in 2019 after a 2.8-mile replacement bridge was constructed. The bridge withstood decades of punishment in a harsh windy, salty environment, including numerous tropical storms and hurricanes, giving researchers a unique look at how the girders held up and how much more they could take.

The N.C. Department of Transportation, through a partnership with N.C. State University, salvaged the old bridge’s concrete girders and had them transported to NCSU’s Constructed Facilities Lab in Raleigh for stress testing.

The tests determine where weaknesses develop in the girder under constant regular use. The girders are also put under extreme pressure until they break.

“What we’re trying to really investigate is the amount of prestressing in this structure,” says Dr. Giorgio T. Proestos, NCSU assistant professor, on a recent NCDOT video (watch at the end of this story).

“Is it enough or should there be less? And how does that prestressing change throughout those 60 years?”

Researchers at N.C. State University conduct stress tests of a girder from the former Bonner Bridge to the Outer Banks.NCDOTAccording to the NCDOT, it took 20,000 pounds of pressure to break one of the bridge’s girders. Sensors with cameras show how the girder reacts under pressure.

“Based on the results of the experiment, there might be changes in the way things are done moving forward,” Proestos says.

The Bonner Bridge was built in 1963 over the Oregon Inlet between the mainland and the Outer Banks. Demolition and dismantlement of the bridge began in 2019 after the Marc Basnight Bridge opened.

“This is a very unique opportunity,” says Neil Mastin, who manages NCDOT’s Research and Development unit. “It’s not often you get a bridge in that extreme environment for nearly 60 years that was intact enough that we can actually use it for testing.”

Mastin says NCDOT will publish the test results, which could have a national impact on bridge design and construction.

Check out NCDOT’s video below of the girders undergoing stress testing:

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IREL Recruitment for Graduate/Diploma Trainee and Others with 54 Posts vacancies, last date to apply is 05-10-2021

The post IREL Recruitment for Graduate/Diploma Trainee and Others | 54 Posts | 05-10-2021 appeared first on ConstructionPlacements.

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The new JLG 1075 telehandler is a 10,000-pound class telehandler designed to increase productivity with its 75-foot lift height that reduces the need for more costly cranes on the job site. Capable of taking loads up to eight stories, the JLG 1075 also features 60-feet of forward reach and 30-feet of up-and-over reach for more precise load placement.

Frame leveling up to eight degrees aids setup on uneven ground. Lift capacity at full height is 6,000 pounds and max reach at 2,100 pounds. A 160 horsepower Cummins engine powers the unit and provides 22,500 pounds of drawbar pull. A right-side electronic mirror with dual cameras enhances safety by allowing operators to see more.

Komatsu forklift hydrostatic drive lowers maintenance costs

The Komatsu FH100-160-1 is designed for heavy loads and long-term durability.KomatsuKomatsu’s new FH100-160-1 series of forklifts borrow technology from the company’s loaders, dozers and excavators including a hydrostatic drive that eliminates wear on drive and brake components. According to the company, the power and design of the FH100-160-1 forklifts make them good choices for industries where heavy loads are common, including freight and logistics, shipping and ports, manufacturing, construction, metal industries, oil and gas, and recycling and waste.

Compared to traditional torque converter systems, the hydrostatics on the FH100-160-1 reduce maintenance costs, fuel consumption and downtime. Sealed wet multiple-disc brakes provide protection from dust, dirt and debris, durability, fade and water resistance, and prompt, reliable braking in high-cycle operations.

New Tadano crawler crane fills gap in market

The flexible track position system on the Tadano GTC-1600 offers multiple different track width setups.TadanoThe Tadano Group has launched an all-new 160-ton tele-boom crawler crane: the Tadano GTC-1600. Designed to fill a gap in the telescopic boom crawler market, the Tadano GTC-1600 has more than 200 feet of main boom length and the ability to work on out-of-level slopes up to four degrees.

The six-section boom extends from 42.8 feet to up to 200.1 feet. The boom uses a single cylinder telescoping and pinning system to extend and retract all the sections automatically and can be locked in selected working positions.

Complimenting the boom is a 33.8-foot by 59.1-foot bi-fold jib with offsets up to 40 degrees. A jib length of up to 105 feet is possible with two 23-foot optional lattice inserts, for a maximum tip height of 305 feet. An optional 11.8-foot heavy-lift jib with 20-degree and 40-degree offsets is also available for tilt-up work in tight spaces.

Tadano’s Opti-Width flexible track position system gives you a numerous symmetrical and asymmetrical track-width setups without requiring you to pin the track frames in fixed positions. The GTC-1600’s hydraulic system makes for smooth and seamless multi-function operation, allowing travel, hoisting, and boom telescoping all at the same time.

Grove updates TMS9000-2 truck crane for more power and faster setup

Grove’s refreshed TMS9000-2 truck crane lost 1,000 pounds and gained 25 horsepower.Manitowoc

With the addition of the new Cummins X12 Tier 4 Final engine, Grove’s TMS9000-2 truck crane gains an extra 25 horsepower and now puts out 475 horsepower. In addition, changes to the outrigger design and placement enhance setup procedure, while a new rear-access ladder option adds practicality for day-to-day use.

The rear outrigger box has been raised by just under five inches to improve the departure angle to 18-degrees, while the front outrigger jacks have been raised 3.5 inches to improve ground clearance. This also makes sliding outrigger mats underneath the pads even easier. Additionally, there is now an extra three inches of outrigger stroke, while the outrigger pad size has been increased from 20 to 24 inches.

According to Manitowoc, the Grove TMS9000-2 has the lowest GVW in the 115-ton class, and the latest model has slimmed down by 1,000 pounds to a svelte 80,311 pounds for the basic configuration. The truck crane’s load charts remain unaffected, courtesy of the 36 x 169 foot six-section Megaform boom and its single telescopic cylinder with fully hydraulic twin-lock pinning system. Manitowoc’s automated laser-welding process leaves just one weld seam on the boom, rather than the previous three, to produce a higher-quality, stronger and lighter design.

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