|
Tribeca Green
New York, NY
Buildings Home
> Case Studies: Green Buildings> Tribeca Green
 This
27-story, 357,000 sq. ft. luxury “green” high-rise residential
building is located on North End Avenue overlooking Tear Drop Park
in Battery Park City in lower Manhattan. The $75 million tower designed
by renowned architect Robert A. M. Sterns of New York City, it contains
270 condominium units, ground floor retail spaces, a business center,
cellar level MEP facilities, a basement level garage and a vegetated
“green” roof.
Designed to comply with both the New York State and Battery Park
City Authority “Green Building” Program, the project
achieved LEED Silver compliant status. As such, Tribeca Green attempts
to offer a fresh opportunity to lead a healthier, more eco-friendly
lifestyle. Energy efficiency measures abound throughout the project,
and consequently the building offers a host of environmentally-friendly
features including energy-producing photovoltaic solar panels, a
cogeneration system and a microturbine that will supply clean energy
for a portion of the building needs.
 Tribeca
Green is a reinforced concrete flat plate structure designed by
the structural engineering office of DeSimone Consulting Engineers
of New York City. Selecting concrete not only provided an innovative
means by which to achieve green, but also provided a versatile structure
to meet the project’s architectural requirements and lateral
load demands.
Situated on fill created by excavation of the former World Trade
Center, and adjacent to the Hudson River, the site hosts very poor
soil conditions. The location posed many challenges for design and
construction. To accommodate the situation, numerous 12-inch diameter
200-ton compression piles were extended through the landfill to
bear directly on the bedrock below. The building’s lowest
level is a 12” thick structural pressure slab, which enables
the building to resist the site’s aggressive hydrostatic pressures.
 The
building’s superstructure is 255 feet tall. Concrete strengths
vary depending upon location requirements. Basement pressure slabs,
black water walls and slabs and pile caps all utilize 5,950 psi
concrete. Exterior foundation walls use 4,000 psi. Columns, shear
walls and transfer mat slabs use 8,000 psi concrete with silica
fume for added strength. To meet LEED ratings, the structure’s
concrete mix utilized a high percentage of slag. In the 8,000 psi
mix, slag replaced approximately 47% of the cement, and in the 5,950
psi mix, slag replaced exactly 50% of the cement.
Because a network of beam elements was too difficult to achieve,
transfer slabs were utilized at 2 floor levels. At the 15th floor,
concrete columns were discontinued and again transferred to accommodate
the roof garden setback and the new architectural layouts. A 28”
mat slab was used to handle the shifted loads. At the 25th floor,
columns were discontinued and transferred using a 14” mat
slab.
 In
general, the design also accommodates heavier loads than normally
found in residential design. The sidewalk slab was designed for
superimposed dead loads of 150 psf and live loads of 600 psf. At
the 15th floor, superimposed dead loads of 200 psf were used to
accommodate the roof garden. Black water tanks required a live load
of 650 psf, and a storm water tank required a live load of 450 psf.
The bulkhead roof slab, was designed to support a water tank weighing
in excess of 127,000 lbs. In addition, the concrete structure was
also designed to support solar panels attached to the façade
of the building. Already penalized by a terrible site coefficient,
this added superimposed dead load contributed greatly to the high
seismic forces.
The structure’s lateral support is comprised primarily of
interconnected shear walls and “link” beams. Thicknesses
vary from 12” to 16”, and in some instances are fortified
with 3 layers of vertical reinforcement to accommodate tension forces
generated by the high seismic loads.
To aid the project’s fast paced construction schedule, 8”
thick reinforced concrete flat plates were used with studrails to
augment punching shear capacity were used extensively throughout
the building to. These studrails help alleviate the congestion of
reinforcing steel around columns while preventing punching shear
distress caused by many adjacent mechanical openings.
 A
key advantage of conventional flat slab systems is the reduction
of floor to floor heights which significantly reduced the cost of
formwork and building frame. The flat-slab lends itself to the use
of conventional plywood construction while the lower floor to floor
heights allow for the use of conventional stick shoring. Building
each floor on a two-day cycle is facilitated by selecting this floor
system with the simplified formwork it offers. While an aggressive
construction schedule, the two-day cycle is the preferred method
of construction in New York City. This trend was set in the late
sixties and made possible by the moderate spans and lower floor
to floor heights common in residential hi-rise flat-plate construction.
Unprecedented in residential building construction, the two-day
cycle reduced the floor completion schedule by 50% compared to an
equivalent structural steel floor system.
|
 |
Case Studies:
Cultural Buildings
Educational Institutions
Green Buildings
Healthcare
Hospitality
ICF Buildings
Luxury Residential
Mixed Use
Office Buildings
Religious Structures
Tilt-Up Buildings
| Developer: Related
Companies
Owner Representative: Battery Park
City Authority
Construction Manager:
Bovis Lend Lease
Architect:
Robert A. M. Stern
Structural Engineer: DeSimone Consulting
Engineers
Concrete Hi-Rise Contactor: Northside
Construction
Superstructure Concrete Supplier: Quadrozzi
Corporation
Foundation
Contractor:
JCivetta & Sons
Foundation Concrete Supplier: NYCON
Supply Corporation
|
|
|