According to the developer, it was impossible to build a tower of this height using conventional construction methods, so a clumsy triangular location near the Greektown neighborhood was chosen for the project. It would have prevented the use of tower cranes.
Liftbuild’s construction system is a hypermodular version of the “lift slab” technology that has its roots in the early 1950s. However, in the latest iteration, it works like this: First, the foundation is prepared and a number of central spines are constructed to accommodate the stairs and elevators to the full height of the building.
Then build each floor from the roof down to the ground, from steel and concrete slabs, to facades, flooring, walls, electrical, plumbing, fire protection, ducting, and more.
Riftbuild/Burton Marlowe
Liftbuild works with a variety of contractors to ensure that everything is done on the ground where possible, prefabricated parts can be quickly installed, and factory-type assembly that minimizes lifting realize the area. Anything that needs to be installed under the slab can be done by jacking it up all around the spine to a comfortable working height.
As each 500-ton floor is ready, eight powerful strand jacks lift it to the top of its spine. It takes about 10 hours to lift the top floor. And once installed, a unique bolted connection permanently locks the floor to the spine. For Exchange buildings, no further structural supports or trusses are included. Each floor is a cantilever design supported only by his two spines, so there are no outside pillars to block the view from the occupants’ windows. In fact, there are no interior walls or stone pillars other than two spines. So designers can take each floor out into the city and lay it out however they like.
Liftbuild’s parent company, Barton Marlow, led the design and construction and funded the project to demonstrate its capabilities. The company says this should be a big leap forward in terms of worker safety. Because when your spine is upright, you don’t have to work at heights or hang from the outside ropes.
And, of course, we need to be able to install these things cheaper and faster. Liftbuild says it’s 10-20% cheaper, up to 50% faster and uses significantly fewer workers than regular construction, but it’s improved methods will allow construction partners and contractors to do more in future construction. We need to prove these claims. Find out how to best use your system. Either way, you’ll definitely have less crane rides and less stairs.
As of late January, all the liftable floors have been lifted and locked in place, leaving only the bottom two floors, which are conventionally constructed. “We are extremely pleased with the results of our first proof of concept of the Liftbuild technology. Our implementation of our unique method has proven to produce the benefits we had expected, achieved with Exchange Building. We are confident that the results presented will set Liftbuild ready for broader commercialization. With this milestone, we are transitioning to improved safety, improved labor efficiency, and improved project stakeholders. We will focus on the next opportunity to deploy the Liftbuild methodology to achieve a shorter schedule for
Riftbuild/Burton Marlowe
The Exchange is the first American example of this kind of building technique, although earlier and incomplete versions of the lifted slab concept had been used before. Perhaps best known is Lambiance Plaza in Connecticut, which collapsed during construction due to shoddy supervision and poor planning, killing 28 workers.
Most recently, in 2018, TGE LLC used technology similar to Liftbuild to construct two 10-story L-shaped office buildings in Bangalore, India. You can see how his previous TGE build launched in the timelapse below.
SRR3 new construction 2017
Source: Liftbuild by Engineering News-Record
