Transcript Final Presentation

Design and Analysis
of 110 Third Avenue
Anthony Nicastro
Structural Option
Advisor: Walter Schneider / Ali Memari
The Pennsylvania State University
110 Third Avenue
New York, NY 10003
Spring 2006
Overview
•Building Description
•Existing Structural System
•Problem Statement and Proposed Solutions
•Design Work:
•Floor Layout/Column Design
•Floor Slab
•Lateral System
•Breadth Work
•Building Envelope Design
•Cost and Constructability of PT slabs
Building Description
Project Team
OWNER: TOLL BROTHERS INC.
ARCHITECT: GREENBERG FARROW
STRUCTURAL ENGINEER: AXIS DESIGN GROUP
MEP ENGINEER: MGJ ASSOCIATES INC.
GEOTECHNICAL ENGINEER: LUNGAN
CM AGENT: TISHMAN CONSTRUCTION
CONSULTANT: LZA/THORTON-TOMASETTI
Building Description
Architecture
•Net Square Feet: 107,100 SF
•Usage:
Primary Occupancy- Residential
Secondary Occupancy- Retail, Floor 1
•Number of Stories: 21 above grade, 2 below
•The exterior walls of 110 Third Ave. consist of
a “window wall” system. This system is fixed
window units fabricated with flush aluminum
panels finished to match the window wall that
rests on the slab.
•On the North and East sides of the building
are balconies from floors 8 through 16 and 16
through 21, respectively.
•Setback at floor 16
Building Description
Electrical
•Electrical service is brought into 110 Third
Avenue by Con-Edison service 120/208V 3
Phase 4 wire distributed to two
switchboards located on the cellar level.
•Switchboard 1 services the residential
portions of the building, retail space, and
gym area Switchboard 2 powers utilities
such as the sprinkler system, fire pumps
and elevators.
•Circuit wire sizes are most commonly 2
#12-3/4”C, and branch circuit breakers
are most commonly 1 pole, 20 Amp.
Building Description
Lighting
•Kitchen Fixtures:
Recessed ceiling downlighting.
Continuous undercabinet task lighting.
Pendant task lighting above island countertops.
•Bathrooms:
Recessed ceiling downlighting.
Mirror task lighting.
•Walk-in Closets:
Utility wall Sconce.
•Apartment Halls:
Recessed ceiling downlighting.
•Common Residential Corridors And Elevator Lobbies:
Recessed ceiling downlighting
Building Description
Mechanical System
•2400#/hr and 2,400,000 BTU/hr. steam
supply
•Heat exchanger supplies individual units
via individual hot water unit heaters.
•A second heat exchanger serves the
primary condenser water loop and is tied
to a 2-cell cooling tower serving the
water-source heat pumps at 990 CPM per
tower with 330 tons capacity per tower.
•CFM total is 48680
•Common spaces are conditioned by a
dedicated VAV box rated at 1040 CFM.
Building Description
Structural System
•CIP concrete system
•8” two-way slab system
•Loads are carried from the two-way slab system to concrete columns
ranging from 12x12 to 40x12
•Concrete columns recessed from perimeter approximately 10” to allow for
non-bearing exterior panels
•The only beams present in the structure surround the elevator core and
stairwell, and also grade beams in the basement level that extend to the
face of the building.
•Roof is flat slab system with roof drains nested under pavers
•Footings range from 4’6” square up to 15’ x 9’6”
•Shear walls extend entire height of the building and are located around the
elevator core.
Structural System
Floor system:
•68’ x 75’
•Typical bay size is 12’ to 15’ square
•Loading:
•25 psf DL, 40 psf LL in apts.
•100 psf LL in stairs
•5000 psi Concrete slab, 8” thick typ.
Structural System
Vertical Elements and
Considerations:
•Height restriction of 210’
•21 Stories each approximately
9’-8” except for lower floors and
penthouse
•5000 psi concrete columns
Structural System
Lateral System
•Two-part system
•Shear walls surrounding the
elevator core
•Columns and floor slab cast
monolithically form a moment
frame
Structural System
Structural System
North Elevation
THIRD AVENUE
Structural System
West Elevation
Problem Statement and
Proposed Solutions
• Create a design that meets the height
restriction while including the most floors
possible with the most space possible.
• Floor system must remain 8” thick or
thinner
• Maintain strength of system without
compromising span length
• Ease of construction/installation
Problem Statement and
Proposed Solutions
Depth Work
• Column design
• Floor system design
• Lateral force resisting system design
– Shear wall only
– Combined system
Breadth Work
• Building Envelope Design
• Cost and Constructability of PT slabs
Column Design
• Design floor layout to support larger bays
with fewer columns
• Initial Design:
– Leaning columns, moments from uneven floor
loading only
– PCA COL aided in design of reinforcement
– Hand check of column to insure PCA COL
accurate design
Column Design
• Final Design
– Columns take moment from lateral forces
– Forces on columns taken from ETabs and
reapplied in PCA COL
– All columns remained the same size except for
columns 7 and 8 which increased by an inch in
one direction
• ETabs showed no change in cross sectional area
• PCA COL showed an increase of 1 inch was necessary
Column Design
Column Design
Column Design
Column Design
Architectural Impact of New Column Layout
Floor Slab
• Design post-tensioned slab using
RAM Concept as an aid
• Keep slab 8” thick
• Banded tendons at column lines
Floor Slab
Latitude Tendons
Floor Slab
Longitude Tendons
Floor Slab
Floor Slab
Floor Slab
Lateral Force Resisting System
• Examine a new lateral system:
Shear walls only
Lateral Force Resisting System
Lateral Force Resisting System
• Design the old lateral force resisting
system, a combination system, to
adapt to the new floor layout
Lateral Force Resisting System
Lateral Force Resisting System
Lateral Force Resisting System
Lateral Force Resisting System
Building Envelope Design
• The window-wall system could have
several water penetration issues develop
over the course of the building’s life
• Barrier system that should repel water
and not allow any penetration whatsoever.
• Wall sections provided by the architect do
not show some critical transition points
between materials.
Building Envelope Design
Building Envelope Design
Building Envelope Design
• In the case of 110 Third Avenue, the wall
system provides no way for the glazing
pocket to drain
• Operable windows need a way to drain, so
there should be some way for them to
drain along the sill track.
• The sill track should have weep holes that
can give the water a way to escape the
system without the tendency to penetrate
through to the inside.
Building Envelope Design
Building Envelope Design
•Gaskets should have fully
vulcanized corners—tend to shrink
over time
•Clear sealer applied to exposed
concrete
•Double sealant joint at the head
and the jamb
•Installation of a swing stage
Building Envelope Design
Building Envelope Design
•Addition of a waterstop and
waterstop slurry where floor slab
meets parapet
•Addition of a protection board
underneath the drainage panels—
supplement the system
•Flashing at the ends of the
parapet should continue all the way
down past the pedestal
Cost and Constructability of PT Slabs
• Cost of original, regularly reinforced
floor slab per floor:
$36,994
• Cost of new, post-tensioned slab per
floor:
$40,090
Cost and Constructability of PT Slabs
• Offsetting costs
– Less construction time: Fewer columns
– Less formwork
Cost and Constructability of PT Slabs
• Constructability
– PT contractors not readily available in
the NY metropolitan area
– Contractors from New Jersey
Summary and Conclusions
• PT floor slab not conducive to the New
York construction market because of
availability issues
• Anywhere else, i.e., Washington DC, they
are comparable designs
• The new design for 110 Third Avenue
functions well within the bounds of code
requirements and can be considered a
valid design for the future.
Comments/Questions