When the last justice center in Bucks County, Pa. was built, the county’s population was only 310,000, and there were four judges to handle the case load. Today, this county located northeast of Philadelphia has more than 625,000 residents, and 13 judges. Construction of a new, modern justice center to handle all of the legal activities is well past due.
County officials broke ground on the $84 million Bucks County Justice Center in Doylestown on July 19, 2011. When the time came for general contractor Ernest Bock and Sons of Philadelphia, Pa., to subcontract the building’s 11,000 cubic-yards of concrete work, one company was at the top of the list: Carson Concrete Corporation of Boothwyn, Pa.
“The project requires 1,100 ready mix trucks delivering concrete for the footings, walls, and 300,000 square feet of floors,” says Anthony Samango, vice president of Carson Concrete Corp. “We will also use 500 tons of reinforcing steel.”
Carson is no stranger to high-profile commercial concrete projects. The contractor helped to construct the Philadelphia Phillies baseball stadium, and its crews completed the concrete frame work of the 50-story St. James Place apartment complex in Philadelphia. “Since 1977, we’ve completed more than 800 jobs, poured millions of yards of concrete, set 30,000,000 ft2 of formwork and placed 100,000 US tons of rebar,” says Samango.
Heart and Soul
Securing the new justice center project meant Carson needed a new crane. Company officials were looking for a rugged and reliable crane that would efficiently handle numerous picks every day of the project, from start to finish.
Since the crane would be operating on an undeveloped site, Carson ruled out truck and crawler cranes, preferring the rough-terrain crane design. “Truck cranes are better rental units, used for a one-day job at a developed site,” Samango says.
Tom Limbach, sales training manager for Terex Cranes, adds, “Truck cranes may not be designed for consistent use on undeveloped sites and lattice-boom crawlers do not offer the flexibility of a telescopic boom found on a hydraulic crane. You have to remove sections of a lattice-boom crawler crane’s boom to change the length, which is inconvenient on a confined site.”
Bottom line, Carson needed a reliable rough terrain crane to work at the site. “We were looking for a utility crane that moves all day, every day,” says Samango. “The crane must lift and place formwork, reinforcing steel and concrete, virtually anything we need it to.”
A recent change in Pennsylvania’s regulations for crane operation meant the 70-ton Terex RT670 RT crane was the right choice. Prior to May 2011, any crane with over 40 tons of capacity required two workers for crane operation. After this time, regulations were updated which moved the benchmark to 80 tons. This gave Carson the option of choosing a much higher capacity crane to complete the justice center project.
During the purchasing process, Samango visited the Terex RT crane manufacturing facility in Waverly, Iowa. He met with Limbach and Tony Marlin, eastern sales director for Terex Cranes, to discuss his options. He watched the line as Terex team members built the RT670 rough terrain crane and operated one himself.
“The RT670 met all the specs we needed, and it was the largest rough terrain crane we could operate with one person,” explains Samango. So Carson bought the RT670 initially for the justice center project and then for future applications of a similar nature.
Big Crane Features
Used for fast-paced, heavy-duty lifting to support the concrete construction efforts, the Terex RT670 will be at the Bucks County Justice Center jobsite for about four months. Carson’s operators have it set up with a two-part line. The crane’s 111-foot telescopic main boom offers plenty of length for lifting to support the concrete work on the 9-story building. When the need arises in the future, the available 57-foot off-settable jib offers a 170-foot maximum tip height.
The RT670 boasts the same undercarriage of the larger 80-ton Terex RT780 Rough Terrain crane. This gives the RT670 a heavier undercarriage and a wider, 24-foot fully extended outrigger footprint than similar class models, which assists with setting the large wall panels. “The 80-ton undercarriage provides a stable platform and rock-solid lifting performance for Carson’s crane operator,” says Limbach.
Powered by a 215-hp Tier 4 interim (Stage IIIB) compliant diesel engine (with an optional Tier 3/Stage III engine available for markets not using ultralow sulfur diesel fuel), the RT670 features three independent hydraulic pumping systems. This affords simultaneous operation of crane functions – including lifting and slewing – without losing performance.
Electro proportional joystick control takes the heat generated by hydraulic controls out of the cab. Additionally, lever effort for crane movement is minimal, and lever response is unaffected by ambient temperature change.
“Our operators also like the dual (axis) joystick feature of the RT670,” says Samango. Limbach explained that most cranes in this class have two single-axis levers, one for fore and aft movement and another for side to side. “The RT670’s responsive controls combine both functions into a single joystick, providing easy operation,” he adds.
This helps to improve lift efficiency at the justice center jobsite, especially when working with the formwork for the walls. These forms are constructed of 9-ft square panels consisting of plywood and steel. The panels are maneuvered, clamped together and lifted into position with the RT670.
For this project, the wall panels reach a height of 35 feet. With its 70-ton rated capacity, the RT670 gives Carson’s crew plenty of options for working with large panel sizes. “We can pick larger, heavier items with the 70-ton crane, which would have to be otherwise broken up into multiple picks with a smaller crane,” mentions Samango. “The RT670 allows us to make fewer picks and save time.”
Another time saver for Carson’s operator is the on-board computer system, which Samango says is very easy to learn. “This is just one more of those big crane features found in the smaller RT670,” says Limbach. “The system uses a pictograph intuitive display, so it is very easy for the operator to adjust settings and operate the crane.”
Assisting with formwork construction and placing, loading and unloading trailers and helping to deliver concrete where it’s required, the RT670 must be fast and efficient to keep workers busy and the project on schedule. Its two-speed main and auxiliary winches deliver on-the-fly shifting between high and low speeds and offer a maximum 533-ft/min winch speed. It also offers a strong, 18,450-pound maximum winch line pull.
From formwork to concrete, the Terex RT670 has consistently risen to every lift challenge presented by Carson’s crews thus far. With its three steering modes—front wheel; four-wheel concentric; and four-wheel crab—it quickly navigates around the site cluttered with rebar and panels. Probably more important, its four-wheel drive helps ensure “it doesn’t get stuck in the mud,” says Samango.