TTen Hudson Yards is one of the very first concrete office buildings in NYC. This 50 story 895-foot tall project consisted of 107,000 cubic yards of concrete. This building is the first structure of a 17,000,000 square foot complex on the west side of Manhattan. This project was built over an existing railroad yard which remained open during construction. In addition to the railroad yard, 10 Hudson Yards had to straddle the Highline; a well-used park converted from an old elevated train track.
This project is one of the very few post-tensioned buildings in NYC. The design required high strength concrete of 14,000 psi in its foundation and lower shear walls. Slag was used to get the required strength (surpassed by achieving 16,000 psi) while also minimizing heat gain in mass concrete. Slag helped in the finishability for the ceilings which optimized floor to ceiling elevation (without hung ceilings). The structural system was composed of high-strength concrete shear walls and post-tensioned beams using a filigree slab system. Without the added strength given by the slag, this innovative design would not have been possible. The 14,000 mix design consisted of 350 lbs. of cement, 700 lbs. of slag, and 50 lbs. of silica fume, and achieved over 16,000 psi.
This project achieved high strength while meeting the stringent specifications for mass concrete. Slag finishing attributes were required to use exposed concrete to create a loft-like experience in lieu of the standard hung ceilings. Slag’s workable consistency and finishability was a huge contributor to this success.
This building was designed to arch over the existing railroads of NYC and incorporated the beautiful “Highline” tourist walkway through the actual lobby of the structure.
Project credits: Related Companies and Oxford Properties Group, Owner; Kohn Pederson Fox Assoc., Architect; Thornton Tomasetti, Engineer; Tutor Perini, Contractor; Empire Transit, Concrete; LafargeHolcim, Slag Cement