It's a project that kicked off in February 2014 with the largest continuous concrete pour as determined by GUINESS WORLD RECORDS. Since then, the mixed-use Wilshire Grand project in downtown Las Angeles, owned by Korean Air Lines Co., Ltd. (Korean Air), has been progressing vertically with the help of two Putzmeister BSA 14000 Trailer Pumps, four Putzmeister MX 34/38Z Placing Booms and one Putzmeister Placing Boom Tower. After more than two years of work, the project has 'topped out' its concrete and steel core at more than 800 feet.
Upon completion in 2017, the new, 73-story Wilshire Grand project in downtown Los Angeles will be the tallest structure west of the Mississippi. To coordinate the fleet of pumps, including 16 Putzmeister America, Inc. (Putzmeister) units, required for the record-breaking, 21,200-cubic-yard (19,400m3) mat pour, Turner Construction Company, the project’s general contractor, worked with Conco Construction Companies (Conco), one of the largest pumping and belt companies in the U.S. The pour included 227 ready mix trucks making more than 2,100 trips and pouring 82 million pounds of concrete during an 18 ½-hour period.
With the foundation in place, the crew has been working on the attached parking structure and 73-story building that will make up the Wilshire Grand project. Both of the existing Putzmeister MX 34/38Z Placing Boom Towers that were used for the mat pour have remained in place while the crew builds up. Two additional Putzmeister MX 34/38Z Placing Booms were constructed to help place concrete for the underground parking structure, and the two Putzmeister trailer pumps used on the mat pour have also remained on site to pump the concrete to the placing towers.
“We utilized Putzmeister equipment because of its proven durability and reliability,” said Doug Marquis, general manager at Conco. “With a high-profile job like this one, it’s essential to have the highest-quality equipment in place to minimize any potential for break downs and help keep the project on schedule.”
In total, the crew has pumped approximately 160,000 cubic yards (122,330m2) of concrete vertically, including lightweight concrete and 8,000 psi mixes. A building of this height requires a pump that can maintain a balance between power and pressure to be able to deliver concrete floor after floor. The amount of friction that is generated during the pumping process as the concrete moves through the lines increases the higher the concrete is pumped. That friction has a significant impact on the plasticity of the concrete at the point of placement. Having the proper equipment helps minimize the amount of labor necessary on the deck to place and finish the concrete, allowing for a more aggressive schedule.
“The Putzmeister 14000 electric and diesel pumps performed flawlessly to push concrete over 1,165 horizontal and vertical feet,” said Michael Marchesano, Turner Construction’s general superintendent.
Wilshire Grand is a podium-style high-rise, which means it has a “podium” or base section spread out at the foot of the building; from that base, the much taller tower is erected. After the base—the first few floors that comprise the retail and restaurant space—was poured, the setup consisted of one placing boom on the main tower, as well as three on top of the podium.
The two Putzmeister BSA 14000 Trailer Pumps worked in conjunction with the placing systems to deliver 90 percent of the concrete for the job. The setup allowed for multiple concrete placements to occur concurrently in order to meet the aggressive construction schedule. Additionally, a Putzmeister 36Z-Meter. Truck-Mounted Concrete Boom pump was used to place concrete on the lower levels of the structure, allowing for more flexibility in range.
Once the crews started working on the vertical placement for the tower of the structure, they utilized a single placing boom on a tower climbing system. The typical vertical concrete floor was placed on a four-day cycle, which included jumping the climbing system.
“This strategic setup was the result of project upfront planning by Turner Construction and Conco. These measures maximized the rewards of using the Putzmeister pumping equipment,” added Marchesano. “Every detail was measured, including redundancy pump station location, system sizing, and layout to enhance safety and avoid building sequence delays.”
As the largest Asian provider of air service to Los Angeles, Korean Air has had a significant impact on the region’s economy for decades. In 1989, the company purchased the original Wilshire Grand building because it recognized the need for world-class accommodations in Los Angeles, and planned to eventually create that true luxury flagship hotel in the internationally traveled city. The Wilshire Grand project will continue Korean Air’s investment in Los Angeles by infusing more than $1 billion into the local economy.
The Wilshire Grand Center will not only boast luxury hotel rooms, but also cutting edge restaurants, businesses and attractive nightlife offerings. The project will play a critical role in the city’s commitment to add 5,000 new hotel rooms citywide—contributing to 20 percent of that goal.
Owner/Developer: Korean Air Lines Co., Ltd. – Seoul, South Korea
General Contractor: Turner Construction Company – New York, NY
Equipment Owner: The Conco Construction Companies – Concord, CA
Ready Mix Concrete Provider: Catalina Pacific Concrete Company – Glendora, CA
Equipment: (2) Putzmeister BSA 1400 Trailer Pumps, (4) Putzmeister MX 34/38Z Placing Booms and (1) Putzmeister Placing Boom Tower, (1) Putzmeister Thom-Katt® TK 50 Trailer Pump, (1) Putzmeister 36Z-Meter Truck-Mounted Concrete Boom Pump.