a tram stop for vancouver

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A STREETCAR SHELTER FOR THE ARBUTUS CORRIDORA STUDIED SIMPLICITY: EXPRESSING THE W-SHAPE

BENJAMIN BYE | ARCHITECTURE 462 | THURSDAY NOON LAB | LAUREN GARVEY

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SIMPLICITY IN STEEL

In the design of a steel streetcar stop for the Arbutus Corridor in Vancouver, B.C. the exploration of structure as ornament was made. Taking precedent from the structures of Mies Van Der Rohe, the streetcar station showcases the steel that makes its structure. To exemplify and showcase the steel, W-shape mem-bers where utilized for their clear identifi ability as structural ele-ments. To strengthen the purity and clarity of the Van Der Rohe infl uenced structure, a simple and clearly defi ned structural hi-erarchy and load distribution was designed. The structure con-tains four levels of member hierarchy. Purlins act as stiffening members, bracing the weak axis of the cantilevered joists. The joists, running cross sectionally, are the primary spanning mem-bers, collecting the initial snow load and material load on the structure. Two longitudinal girders direct loads from the joists into the four columns. The building is braced through the use of moment connections. Bents are created as the columns are connected by spanning joists and girders. To further brace the structure against strong lateral loads the columns are driven into the ground forming a moment connection at the base of the column. Through the process of designing with pure structural intention a truly simple and beautiful structure can be created. With the focus on clarity and purity of structure, a balance of structural effi ciency and articulation was made. Some members were slightly oversized for this cause, giving more importance to the aesthetic possibilities of the structure than could have been achieved with a purely effi ciency based design. The outcome is one of aesthetically reasoned structural design.

< EXPLODED AXONThe axon brakes apart the streetcar stop and exemplifi es the rational simplicity to which the structure was designed. The ar-ticulation of structural members becomes the ornament of the streetcar stop.

PURLINS

JOISTS

GIRDERS

COLUMNS

CLEAR HIERARCHY

IIT Crown Hall. Mies Van Der Rohe. Structure as Ornament

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AXONOMETRIC DRAWING: STRUCTURAL GEOMETRY

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MODEL PHOTOGRAPHS

STRUCTURAL ARTICULATION

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LONGITUDINAL ELEVATION 1/4”=1’

CROSS SECTION 1/4”=1’

20ft

12ft

8ft

8ft

THE STRUCTURAL UNIT DRAWN

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LONGITUDINAL ELEVATION 1/4”=1’

PLAN 1/4”=1”

20ft

12ft

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EARLY DESIGN WORK:THINKING THROUGH DRAWING

left: many different formal and structural ex-plorations where made at the beginning of the design process, and an evolution was made towards the current structural scheme.

above: day dreaming a simple design detail was born that was to be the genesis of the structure.

below: through drawing, geometries and porpor-tions were tweaked until the final scheme was produced.

thinking through drawing.

unsettling proportions early on... considered, balanced, and appropriate proportions...

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.75 snow load: w= .75k/ft

.75 wind load: 1.8k

.75 wind load: 1.8k

.75 snow load: w= .0375k/ft

dead load: w= .12k/ft

dead load: w= .06k/ft

note: the loads are placed on the joist members because ultimately in this design the purlins purposes is to brace the weak axis of the joists. In studying forces flow in the structure, it was most acurate to distribute loads in this man-ner.

MULTIFRAME: AN OVERVIEW OF THE MODEL

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.75 wind load: 1.8k

Moment Diagram: Because of the high level of wind load on the structure, the columns provide the most lateral resistance so they have the highest moments. The moment graph also illustrates the clear necesity for member hierarchy with the col-umns needing to resit the most force, and the purlins the least. The only member with noticeable weak axis bending is the column, which will be illustrated in the column de-sign check.

Mmax for the structure: 4.825k-ft (column)

Axial Stress Diagram: As tributary mem-bers for all loading on the structure, the columns are the main members that need to take compression and tension stresses in mind. The joists between the columns also contain higher compression stresses, acting as bracing members reacting against the high wind load.

Pmax for the Structure: 3.017k (column)

Deflection Diagram: Deflection in the structure is most prominant in the columns with a total deflection of 0.052 inches. The deflection is well below the maximum al-lowed deflection factor. This graph also illustrates how there is a slight torsional effect in the girder due to the support of the joist cantilever. The actual deflection is neg-ligable, it is just exagerated in the deflection diagram.

Total Deflection For Structure: 0.052in

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TYPICAL CANTILEVER JOIST: A-36 Steel | W6 x 9 Shape | Spanning Member

Mx-max : 1.021k-ft

The weak axis My-max is negligable at 0.002k-ft

Pmax : 0.00k

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Max Deflection: 0.005in

Deflection Check:

Allowable Deflection = l = 4ft x 12in/ft = 0.26in 180 180

Allowable Deflection: 0.26in > Max Deflection: 0.005in

passes deflection check

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DEPARTMENT OF ARCHITECTURESchool of Architecture and Allied ArtsUniversity of Oregon

Architecture 462/562Mark Donofrio

Winter 2012

W ShapesStructural Design - Steel Design Spreadsheet

Copyright © 2011 by Mark Donofrio 1 of 2

Designer: GTF:Ben Bye Lauren Garvey

Material Properties: Section Properties:Steel Type: A36 Section: W6X9

Fy: 36 ksi Area: 2.68 in2

Fu: 58 ksiE: 29000 ksi Axis X-X (Strong Axis) Axis Y-Y (Weak Axis)

Ix: 16.4 in4 Iy: 2.2 in4

Sx: 5.56 in3 Sy: 1.11 in3

rx: 2.47 in ry: 0.905 in

Member Data:Member ID: Typ. Cantilever Axial Properties (Column Buckling):

Unbraced Length - X-Axis: 4 ft Unbraced Length - Y-Axis: 2 ftK-Condition: e K-Condition: eK-Value: 2.1 K-Value: 2.1

Member Loads: Axial Tension P: 0 kipsMoment - Strong Axis: Mx MAX: 1.021 kip-ftMoment - Weak Axis: My MAX: 0.002 kip-ft

Axial - Tension Check [AISC Spec D1]:Utilization:

ft: 0.00 ksi < Ft: 22 ksi OK 0.0%

Axial - Compression Check [AISC Spec E2]:

Strong Axis - X: Weak Axis - X:KL/rx: 40.8 KL/rx: 55.7 <-- Governs

Cc: 126.1

Governing Effective Slenderness Ratio:KL/r = 55.7 Cc = 126.1 Therefore, use EQN E2-1 [AISC]

Utilization:fc: N/A ksi Fc: 17.8 ksi N/A

Flexure Check - Strong Axis [AISC Spec. F1]: Fbx = 0.6Fy

Utilization:fbx: 2.20 ksi < Fbx: 22 ksi OK 10.2%

Flexure Check - Weak Axis [AISC Spec. F2]: Fby = 0.75Fy

Utilization:fby: 0.02 ksi < Fby: 27 ksi OK 0.1%


Member ID: Typ. Cantilever

Combined Stress Check:Axial Compression and Bending [AISC Spec H1]:

F'ex: 89.7 ksi F'

ey: 48.1 ksiCmx: 1 Cmy: 1

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Winter 2012



AISC EQN H1-1

AISC EQN H1-2

AISC EQN H1-3

Axial Tension and Bending [AISC Spec H2]:

AISC EQN H2-1

0.00 + 0.10 + 0.00 = 0.10 < 1.0 OK

Section is satisfactory

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TYPICAL COLUMN: A-36 Steel | W8 x 31 Shape | Supporting Member

Mx-max: 4.825k-ft (strong axis)

My-max: 0.646k-ft (weak axis)

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My-max: 0.646k-ft (weak axis)

Max Deflection: 0.052in

P-max: 3.017k compression

Deflection Check:

Allowable Deflection = h = 8ft x 12in/ft = 0.192in 500 500 Allowable Deflection: 0.192in > Max Deflection: 0.052in


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Winter 2012







Ix: 110 in4 Iy: 37.1 in4

Sx: 27.5 in3 Sy: 9.27 in3

rx: 3.47 in ry: 2.02 in

Member Data:Member ID: Typ. Column Axial Properties (Column Buckling):

Unbraced Length - X-Axis: 8 ft Unbraced Length - Y-Axis: 8 ftK-Condition: c K-Condition: cK-Value: 1.2 K-Value: 1.2

Member Loads: Axial Compression P: 3.017 kipsMoment - Strong Axis: Mx MAX: 4.825 kip-ftMoment - Weak Axis: My MAX: 0.646 kip-ft


ft: N/A ksi Ft: 22 ksi N/A



Cc: 126.1

Governing Effective Slenderness Ratio:KL/r = 57.0 < Cc = 126.1 Therefore, use EQN E2-1 [AISC]

Utilization:fc: 0.33 ksi < Fc: 17.7 ksi OK 1.9%






Member ID: Typ. Column


F'ex: 135.5 ksi F'


AISC EQN H1-1

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Winter 2012



AISC EQN H1-2

fa/Fa: 0.02 < 0.15

AISC EQN H1-3

0.02 + 0.10 + 0.03 = 0.15 < 1.0 OK



AISC EQN H2-1

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TYPICAL GIRDER CANTILEVER: A-36 Steel | W8 x 10 Shape | Spanning Member

Mx-max : 1.616k-ft

Pmax : 0k

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Max Deflection: .042in

Deflection Check:

Allowable Deflection = l = 6ft x 12in/ft = 0.4in 180 180 Allowable Deflection: 0.4in > Max Deflection: 0.042in


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Winter 2012







Ix: 30.8 in4 Iy: 2.09 in4

Sx: 7.81 in3 Sy: 1.06 in3

rx: 3.22 in ry: 0.841 in

Member Data:Member ID: Typ. Girder Axial Properties (Column Buckling):

Unbraced Length - X-Axis: 6 ft Unbraced Length - Y-Axis: 4 ftK-Condition: e K-Condition: eK-Value: 2.1 K-Value: 2.1

Member Loads: Axial Compression P: 0 kipsMoment - Strong Axis: Mx MAX: 1.616 kip-ftMoment - Weak Axis: My MAX: 0.01 kip-ft





Cc: 126.1







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Winter 2012




Member ID: Typ. Girder


F'ex: 67.7 ksi F'


AISC EQN H1-1

AISC EQN H1-2

fa/Fa: 0.00 < 0.15

AISC EQN H1-3

0.00 + 0.11 + 0.00 = 0.12 < 1.0 OK



AISC EQN H2-1

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TYPICAL BRACING JOISTA-36 Steel | W6 x 9 Shape | Bracing Member

Mx-max : 2.735 k

Pmax : 0.768 k Compression

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Max Deflection: .02in

Deflection Check:

Allowable Deflection = l = 4ft x 12in/ft = 0.133in 360 360 Allowable Deflection: 0.133in > Max Deflection: 0.02in


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Winter 2012







Ix: 16.4 in4 Iy: 2.2 in4

Sx: 5.56 in3 Sy: 1.11 in3

rx: 2.47 in ry: 0.905 in

Member Data:Member ID: Typ. Brace JoistAxial Properties (Column Buckling):

Unbraced Length - X-Axis: 4 ft Unbraced Length - Y-Axis: 4 ftK-Condition: a K-Condition: aK-Value: 0.65 K-Value: 0.65

Member Loads: Axial Compression P: 0.768 kipsMoment - Strong Axis: Mx MAX: 2.735 kip-ftMoment - Weak Axis: My MAX: 0.02 kip-ft





Cc: 126.1







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Winter 2012




Member ID: Typ. Brace Joist


F'ex: 935.9 ksi F'


AISC EQN H1-1

AISC EQN H1-2

fa/Fa: 0.01 < 0.15

AISC EQN H1-3

0.01 + 0.27 + 0.01 = 0.30 < 1.0 OK



AISC EQN H2-1

a tram stop for vancouver

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