A Concrete Symphony
A Concrete Symphony
As one of the tallest buildings to be built in Hawaii, Symphony Honolulu is a 45-story luxury condominium rising from the heart of the Kapiolani corridor. To assist in its lofty construction, Putzmeister equipment is performing ingenious concrete placing feats with its long-reaching truck-mounted boom pumps and its placing system that has become an integral part of high rise construction techniques new to Hawaii.
Climbing 400 feet into wide-open blue skies, Symphony tower will be home to 388 private residences with floor-to-ceiling windows, boasting panoramic views of the Pacific, Diamond Head and downtown Honolulu. A condo unit averages 1,100 square feet (102m²) and starts at $500,000. The 3.35 acre (1.35 hectare) development is across from the Neal S. Blaisdell Center, home of the Hawaii Symphony Orchestra, thus the tower's name.
The lavish residential high rise features finely orchestrated amenities with 34,000 square foot (3,159m²) of open and recreation space with a grand terrace that includes a fitness center, lap pool and spa, movie theater and party pavilions. The pedestrian-oriented, urban project also includes 80,000 square feet (7,432m²) of commercial space on the lower floors.
Construction is estimated to take about 25 months under the expertise of Honolulu-based Nordic PCL Construction, the general contractor, with Ohana Concrete Pumping, Inc. of Pearl City, Hawaii responsible for the intricate placement of 45,000 total cubic yards (34,405m³) of concrete upon completion in 2016.
From Ground Up
To create the foundation for the project’s huge 270 foot x 274 foot (82m x 84m) footprint, 480 auger cast piles were drilled 135 feet (41m) deep and grout pumped into each hole. Three different mat foundations were required and concrete placed up to an eight foot (2.4m) thickness while employing Ohana’s 43Z- and 47Z-meter truck-mounted boom pumps, needed for their long reaches at more than 150 foot (46m).
The first three floors of the main 45-story tower were pumped using truck-mounted boom pumps before a detachable 38-meter placing boom was installed to take over concrete placement. The contractor is utilizing a hydraulic self-climbing formwork system, so no placing boom tower is needed, as the entire core formwork is raised independent of the crane. This approach is a new concept to Hawaii and a first for most construction crews involved with the project.
Implementing the novel technique, which is designed to increase job site production and reduce labor costs, Tim Rippy, Nordic superintendent says, “We selected this new system because of its self-jacking formwork that meant we didn’t need a crane to climb.”
A Putzmeister clamp down mounting base, specifically designed to accommodate mounting without a tower, was used to fasten the placing boom to the formwork within the elevator shaft. According to Joe Frederick, operations manager at Ohana, “We supplied the cross frame to Nordic who mounted it, which is an easy process as it only requires four long bolts.”
Frederick added, “Now that the new system is in place and the tower rising, it means one less step for us, as we don’t have to jack up the placing boom tower for each level. We just show up and start pumping concrete.”
Typically, a high pressure trailer-mounted concrete pump would be used to pump the concrete to the placing boom; however, a maze of scaffolding surrounded the perimeter of the job site, which prevented its setup.
To overcome this obstacle, Ohana used truck-mounted boom pumps, which had to be set up in the street. They extended their booms over the immense amount of scaffolding to tie directly into the pipeline below the pedestal, using a 90-degree elbow that would deliver the concrete to the placing boom. As the building progressed upward, different sized models were selected, starting with the 43Z-meter for the lower floors, and ending at the sixth floor utilizing the 61-meter, the biggest boom pump known throughout the South Pacific. The boom extended out more than 180 feet (55m) horizontally to deliver concrete to the placing boom.
Upon reaching the seventh floor, a small area on the crowded job site became available to set up a BSA 2110 HP-D trailer pump. At this point, the trailer pump took over delivering the concrete, as it is capable of up to 133 yd³/hr (102 m³/hr) outputs and high 2,176 psi (150 bar) pressures.
“This high profile project is of special significance as it illustrates our company's advancement as we celebrate our tenth year in business," says Kathy Thornberry, CEO of Ohana, a Woman Business Enterprise.
Thornberry explains, “In 2005, we started from scratch with the purchase of one 47Z-Meter Putzmeister boom pump. Just three years later, we had expanded our fleet to seven boom pumps before we were forced to ride out the severe economic downturn. Once our market recovered, we started handling high rise projects, which includes the Symphony that is going strong during our ten year anniversary."
Under the direction of Thornberry and her brothers William Frederick, President; and Joe Frederick, Operations Manager, Ohana's fleet today features truck-mounted boom pumps; placing system that includes pin-connect placing boom towers, hydraulic climbing system, a clamp down base and hydraulic diversion valves; along with a Telebelt® conveyor, and Thom-Katt® trailer pump.
However, even though the company's fleet has grown over the past decade, the models needed for this large-scale job were already committed to other major projects, so the company sought out additional Putzmeister equipment from Ralph’s Concrete Pumping of Seattle, Washington, who supplied a placing boom with a Series II detach and a trailer pump for the project.
“Our entire fleet is Putzmeister so we felt more comfortable getting the same brand from the mainland,” says Frederick. “This equipment arrangement with Ralph’s worked out really well.”
The tower’s design includes 1.5 million square feet (139,355m²) of concrete form work, with a considerable amount of that in a seven-story podium of which the first three levels will house restaurants, retail and a luxury car dealership, the next three accommodate parking and the seventh level is the grand terrace. To place concrete for the podium, a Putzmeister 36-meter placing boom, detached from its truck, is flown between two 40-foot (12m) freestanding towers to access the large footprint. With a simple four-pin connection, the placing boom can be quickly moved from one tower to the next and then easily reconnected.
Another process that accelerated the project's speed was the ease in moving the placing system among the numerous towers. It involved a simple four-pin disconnect from the tower, then picking and moving the boom and pedestal together to the next tower, followed by an quick reconnection with four bolts.Another process that accelerated the project's speed was the ease in moving the placing system among the numerous towers. It involved a simple four-pin disconnect from the tower, then picking and moving the boom and pedestal together to the next tower, followed by an quick reconnection with four bolts.The on-site high pressure trailer pump also supplies the concrete for these two added tower locations, with concrete being diverted accordingly via pipeline strategically placed to accommodate this arrangement.
The SDVH 3/2 hydraulic diversion valve by Putzmeister Pipe Technology is being used for system blow out, as it prevents any movement of the connected delivery line. The leak-proof valve handles 1885 psi (130 bar) pressures at heights up to 985 feet (300m), more than double the height of the Symphony.
The main tower is quickly rising out of the ground with concrete placed to the tenth floor at the start of the new year. “Every project today is on a tight schedule, and Ohana and their equipment have been doing a great job,” says Rippy. “We’ve had no issues at all.”
The high-profile project is on a five-day floor completion schedule so Ohana is kept busy placing concrete on a regular basis. However, mother nature did cause disruptions to the schedule. In recorded history, Hawaii had never been hit by two tropical cyclones in one year. That is, until 2014 when two major storms blew in only two months apart — Tropical Storms Iselle in August and Ana in October.
The threat of both these tropical storms interrupted the project’s timeline, as extra precautions were taken before the storms arrived to button down the hatches and shut down the job. Fortunately, the storms didn't cause much havoc, so crews could resume work soon after the storms passed, but they did contend with the excessive rain that followed.
A Strong Finish
Going green, Symphony is designed with USGBC LEED certified criteria, PV solar panels, EV charging stations in the garage and gray water reclamation. Construction started in November 2013 and completion is slated for early 2016. Nearly 70 percent of the available units sold within the first two days of sales.