Construction Builds around Historic Hanna-Barbera Studio May 2006

“Re-shoring” enables 58-Meter boom pump setup on elevated deck

STURTEVANT, Wis. (May 1, 2006): Hollywood’s Hanna-Barbera, the world's first animated television studio, is transforming its original site into new offices, stores and apartments near Universal CityWalk. Ironically, creative ingenuity similar to what sparked the animation of Scooby-Doo and George Jetson is still common at the site, as contractors undertake ingenious ways of placing concrete while working around the preserved portion of the historic complex.

Built in 1963, the studio closed in 1998 when Time Warner acquired Hanna-Barbera Productions and moved the company. In 2002, Los Angeles-based developer William McGregor purchased the property and proposed razing the three-building complex. The plan drew criticism that a historically significant structure would be destroyed and neighborhood traffic increased. In the wake of this backlash, the developer opted to save and incorporate the historic icon into a scaled-down commercial and residential development.

Today, the main studio building is being converted into office space, an adjacent building transformed into a health club and 5,000 square feet of the third structure developed into retail stores. In addition, a new underground parking garage and three-story, 47-unit luxury apartment building – the Cahuenga Universal Apartments – will rise from the Hanna-Barbera area. All are under the guidance of general contractor American Constructors of Huntington Beach, California.

With space restrictions and limited access from only two sides, working around the original building meant overcoming some construction hurdles. Placing concrete for the slab-on-grade and first elevated deck pour of the parking garage was feasible with concrete boom pumps that could set up and relocate on grade. The two remaining elevated decks, however, posed obstacles.

The option of a crane and bucket was quickly ruled out for lack of efficiency. A second alternative of running 500 feet of delivery system was deemed undesirable, as pumping concrete at around 50 cubic yards an hour would take 14 hours and require ten laborers for each typical 700 cubic yard pour.

Enlisting the long 190 ft. reach and maximum 260 cubic yard an hour output of a Putzmeister BSF 58.20H truck-mounted concrete boom pump proved to be a better alternative. The pump is one of many in the Fleming Concrete Pumping, Inc. fleet. Based in Santa Ana, California, Fleming claims to have the only two Putzmeister BSF 58-Meter boom pumps mounted on “seven-axle” trucks in the United States. Although the seven-axle mounting on a Tor chassis provides greater maneuverability, it also accommodates vehicle restrictions instituted by the Southern California DOT – regulations even stricter than other parts of the Golden State.

Positioning the mighty boom pump atop the elevated parking deck would attain full concrete coverage without dragging hose. However, the elevated parking deck was designed for cars at about 100 pounds per square foot. It would require over a thousand times that amount to accommodate a truck-mounted 58-Meter boom pump with its extremely long reach capabilities.

The solution to this challenge was “re-shoring”, as termed by Clete and Mark Zastrow of Reliance Company in Glendale, California, the concrete contractors for the special project.

“We thought that by using additional vertical shoring posts, we could transfer the weight of a sizeable boom pump on an elevated deck to the ten-inch thick concrete slab-on-grade below,” says Clete Zastrow.

Mark Zastrow took the initiative and found a structural engineering firm to perform the calculations, employing A. J. Miller and Associates of Oakland, California because of their familiarity with cranes.

Mark notes, “The firm’s engineers calculated the extra shoring and additional reinforcement needed to support the BSF 58-Meter atop the elevated deck, taking into consideration the unit’s weight along with each outrigger’s load factor.”

Fortunately, the boom would provide enough reach so its hopper could be positioned at the deck’s edge from either of the two accessible U-shaped sides. This meant ready-mix trucks could remain on grade while discharging concrete and would not need to be figured into the equation.

“This is the first time we’ve used this technique,” says Mark. “Although it may have been done before, I highly doubt it was ever attempted for the substantial size and 34 foot wide outrigger span of a large boom pump.” Once the technique was approved by the engineer of record, the entire re-shoring process took about three hours of installation on each side of the site. As a typical six foot vertical shoring post handles about 7,000 pounds per square foot, the calculations indicated that an additional group of sixteen posts would be required to accommodate each BSF 58-Meter outrigger below the eleven-inch elevated deck.

Consequently, four groups of 16 posts were required for each outrigger. Each group was positioned in four rows with four posts per row, spaced about a foot apart. Although each outrigger has about an 84,000 pound load factor, each was structurally engineered to withstand 112,000 pounds per square foot as an added safety measure.

To more than accommodate the travel path of the entire unit, an 8 ft. wide and 60 ft. long area was also re-shored. It too required 16 posts, but they were grouped in sets of two around the perimeter of the truck’s base while spaced about six feet apart. The area below was re-shored for approximately 140,000 lbs per square foot, which far exceeded the unit’s actual weight.

The two elevated decks require eight pours. All are being reliably pumped with the BSF 58-Meter, and expertly placed and finished by Team Finish, Inc. of Brea, California.

Under the expertise of Fleming’s veteran operator Scott Lee, the boom pump is attaining approximately 170 cubic yards an hour output, taking about four hours to pump and involving minimum labor. Equipment performance, trained operators and attentive service are all key factors that keep Reliance a loyal Fleming customer.

“By utilizing a re-shoring approach along with Fleming’s dependable pump, we’re saving about three months of time,” says Clete. “The outside structural engineering costs are minimal compared to the substantial time and labor savings.”

“The ingenious solution by Reliance reveals that re-shoring can be successfully accomplished with a long reaching boom pump like the 58-Meter,” says Brian Ayres, Fleming’s VP of Sales. “This means contractors struggling with similar situations now have a viable alternative, as long as it structurally meets engineering approval.” Fleming gives Reliance further high marks for their professionalism. “Although setup was critical on this particular project, our operators can show up for any job with Reliance and it’s like driving into a parking space,” adds Ayres. “A line is drawn where the truck cab should stop; and four steel trench plates are used for added safety, being precisely placed in the exact spots needed for outrigger setup. It results in a safe and efficient process.”

In January 2006, Associated Ready Mix of Sun Valley, California dispatched the first load of 4000-psi concrete, and the last load is planned for this July. At that time, over 8,000 total cubic yards of concrete will have been incorporated into the structure, totaling $4.5 million for the concrete work.

SPECS Developer: William McGregor – Los Angeles, CA General contractor: American Constructors – Huntington Beach, CA Concrete contractor: Reliance Company – Glendale, CA Pumping contractor: Fleming Concrete Pumping, Inc. – Santa Ana, CA Place and finish contractor: Team Finish, Inc. – Brea, CA Ready mix supplier: Associated Ready Mix – Sun Valley, CA