Client Longchamp - WordPress.com · Longchamp is a 240 million dollar business employing 800 people in the production of leather products. ! In 2003 British designer, Thomas Heatherwick,

!  Longchamp, a French company based in Paris manufactures and markets fine leather goods including handbags, luggage and accessories.

!  The company was founded in 1948 and opened it’s first factory in 1956.

!  The name “Longchamp” is a tribute to a famous Parisian Horse racing track.

!  Longchamp is a 240 million dollar business employing 800 people in the production of leather products.

!  In 2003 British designer, Thomas Heatherwick, designed Longchamp’s best selling handbag, “The Zip Bag”.

!  Longchamp products are sold in 200 stores across the United States. The SoHo store, profiled in this presentation, is Longchamp’s 100th store worldwide.

Client Longchamp

Project General Information

!  150 tons of steel were used in the overall project

!  Construction time - 111,000 man-hours

!  Overall cost of project - $12,000,000

!  Height of atrium - 60’

!  Cumulative strength of magnets in display features - 13.5 tons (enough to support the weight of 10 N.Y.C. Taxi cabs)

!  Specific to Steel Landscape: !  Cost of steel landscape - $2,000,000. !  Construction time - 27,750 man hrs. (steel landscape only) !  Thickness of steel plates - 1 !” !  Weight - 55 tons !  Dimensions - 27’ x 46‘ x 60’ !  Number of steel “ribbons” - 30 !  Total length of ribbons - 1800’ !  Thickness of rubber strips - 3/16” + 1/16” glue !  Total length of natural rubber strips - 3000’ (equal to the width of Central Park)

!  Materials draw customers from the entrance into the store and up to the second floor.

!  30 ribbons of steel cascade through the core.

!  Floor areas are finished with red maple boards.

!  The building’s original brick walls and cast iron columns are exposed.

!  The ceiling is made from laminated sheets of ash veneer.

!  Display fixtures are fabricated from a variety of widths pale American ash laminated panels.

!  Openings in the ceiling reveal the original textures of the building and the current MEP systems.

Project Materials

!  Materials draw customers from the entrance into the store and up to the second floor.

!  30 ribbons of steel cascade through the core.

!  Floor areas are finished with red maple boards.

!  The building’s original brick walls and cast iron columns are exposed.

!  The ceiling is made from laminated sheets of ash veneer.

!  Display fixtures are fabricated from a variety of widths pale American ash laminated panels.

!  Openings in the ceiling reveal the original textures of the building and the current MEP systems.

Project Materials

!  Materials draw customers from the entrance into the store and up to the second floor.

!  30 ribbons of steel cascade through the core.

!  Floor areas are finished with red maple boards.

!  The building’s original brick walls and cast iron columns are exposed.

!  The ceiling is made from laminated sheets of ash veneer.

!  Display fixtures are fabricated from a variety of widths pale American ash laminated panels.

!  Openings in the ceiling reveal the original textures of the building and the current MEP systems.

Project Materials

!  Materials draw customers from the entrance into the store and up to the second floor.

!  30 ribbons of steel cascade through the core.

!  Floor areas are finished with red maple boards.

!  The building’s original brick walls and cast iron columns are exposed.

!  The ceiling is made from laminated sheets of ash veneer.

!  Display fixtures are fabricated from a variety of widths pale American ash laminated panels.

!  Openings in the ceiling reveal the original textures of the building and the current MEP systems.

Project Materials

!  A “Theater for Retail”.

!  A major piece of Architecture behind an unassuming facade.

!  A topography of walkways, landings, and steps that draw the visitor from the entrance at the ground floor to the second floor.

!  Longchamp wanted a unique architectural ensemble to be appreciated as one of a kind.

!  “If we have no store at the ground floor, then everyone has to go up”. Thomas Heatherwick

!  Upper floors with windows have much more light than if the retail area were located at ground level.

!  Atrium and skylights flood the steel river with light.

!  “Like insects, people are attracted to light”. Thomas Heatherwick

Design Concept

Project Program

1700 SF

THIRD FLOOR | Terrace & Offices

2130 SF

BASEMENT | Storage

1500 SF

GROUND FLOOR | Entry / Reception

TOTAL NET AREA | 9830 SF

4500 SF

SECOND FLOOR | Retail

Support Distribution

Brick Wall

Vertical Support

Lateral Support

!  Retrofitting an existing building (1930s era) with a design this innovative made the structural engineering of the project both unusual and challenging.

!  Structural Interventions on the existing building: !  Addition of third floor !  Repositioning of elevator & egress stairs. !  Punching shaft through floors to allow for stairs,

atrium, and skylight. !  New foundation to support 55 ton staircase. !  Major structural reinforcement throughout building.

!  Live Loads: Roof & Monumental Stair 100 psf 1st & 2nd Floors 75 psf

!  Maximum Stress Allowed : Fu = 0.75 Fy

!  Dynamic Vibration Analysis of the monumental stair design tested both 36 KSI and 50 KSI steel. The results revealed no difference in performance so for economy 36 KSI was used.

Design Structural Stress Distribution

Gre

en S

treet

Spring Street

Second Floor Plan

!  The Monumental Stair is exempt from Fire Protection since there are two other exit stairways.

!  The site contained an existing 36” wide egress stair. A second fire rated (2 hour), 44” wide, egress stair was added.

!  Accessibility to the upper floors is provided by a new elevator enclosed in a two hour fire rated envelope.

!  Maximum actual travel distance of design is 88’ - 5”

Design Egress Plan

Existing 36” Stair

New 44” Stair

88’-5

”

!  The display shelves which line the perimeter of the sales area share the sensibility of the steel stair in that they appear as ribbons of material cut of, but not detached from, the whole.

!  The forms which become the display shelves are softly folded down from the thick ceiling panel and then in turn the individual shelves appear as layers which have progressively delaminated from that thickness of the vertical forms .

!  The voids left by the “peeling down” of the display units reveal the services (MEP) located in the space above.

!  The ceiling and display shelves were fabricated by laminating multiple layers of wood, with the final surface being a fine veneer of natural colored American ash.

Design Display Units

F o r m s F o r m s

!  The display shelves which line the perimeter of the sales area share the sensibility of the steel stair in that they appear as ribbons of material cut of, but not detached from, the whole.

!  The forms which become the display shelves are softly folded down from the thick ceiling panel and then in turn the individual shelves appear as layers which have progressively delaminated from that thickness of the vertical forms .

!  The voids left by the “peeling down” of the display units reveal the services (MEP) located in the space above.

!  The ceiling and display shelves were fabricated by laminating multiple layers of wood, with the final surface being a fine veneer of natural colored American ash.

Design Display Units

!  “The stairway is enclosed by an impossibly etherial glass balustrade, that shimmers like transparent fabric.” Architectural Review

!  The preliminary design was rigid in character and appeared to be an attempt not to compete with the highly innovative stair or to provide a counter point to its curves.

!  Heatherwick Studio was not satisfied with this design and spent the next year experimenting with alternate designs and materials.

!  The result is a balustrade that is as noteworthy as the stair it protects.

!  The balustrade is a series of hand-formed panels fashioned from a thermoplastic referred to as PETG (polyethylene terephthalate glycol). This plastic is generally used for the manufacture of airplane windsheilds and headlight reflectors.

!  True to the nature of hand crafting, each of the 46 panels is unique.

!  Steel uprights welded to the steel stair support both the panels and a very simple steel hand rail.

Design Balustrade

!  Uninterrupted forward and upward circulation.

!  1 !” steel thick rolled steel plates form 30 sinuous ribbons.

!  Stair rises a height of 17’- 5” to the second floor with two landings.

!  Tread depth - 11 " “ | Riser height - 7”

!  Weight - 55 tons

!  Fabrication time - 6 months

!  3/16” thick natural rubber in a warm burnt ochre color is applied to tread (top & bottom since both are exposed).

!  High-powered magnets attach sculptural display forms anywhere on steel “stairs” to display leather goods.

!  The steel handrail is enclosed by thermoplastic panels.

Steel Landscape Physical Properties

F o r m s

F o r m s

Water jet

!  Curved steel templates of the tread profile were cut using a water jet.

!  A water jet uses a jewel nozzle with a 0.004”- 0.015” diameter orifice to pin point a highly pressurized water spray on the material to be cut.

!  The pressure is typically between 20 - 55,000 psi (30 times the pressure of a power washer)

!  A water jet system uses a supersonic erosion process in which stream velocity, not pressure cuts the material.

!  A water jet never gets dull & cannot overheat.

!  Abrasives are often added to pure water to cut tougher materials.

!  The mixture leaves the nozzle at a speed greater that 900 mph.

!  With a 30 HP pump, an abrasive jet can cut #” thick Titanium at a rate of 7” per min.

Fabrication Cutting the Steel

welding

Steel Landscape Fabrication Bending the Steel

!  The steel members were incrementally bent to meet pre-determined profiles.

!  The incremental bending was accomplished using a hydraulic press break.

!  All markings on the steel were eventually ground off .

Chalk marks at regular intervals determine where the Press Break will bend the plate.

The amount of curl is determined by the frequency of Press Break compressions.

The Press Break causes the plate to curl up.

Shear press

!  After the stair was fitted in the shop it was dismantled and shipped in segments to the site.

!  All rigging fasteners and connections were shop-welded.

!  The size of the segments was determined prior to the fabrication according to the installation site’s clearance dimensions.

!  Since no horizontal span was involved, the segment parallel to the wall was fabricated from thinner (1/2”) steel plate.

Steel Landscape Assembly

installation

Steel Landscape Installation Sequence