Aspen Art Museum Creating Innovative Wood Structure

Transcription

1 Aspen Art Museum Creating Innovative Wood Structure Tallinn Wood Architecture Conference November 25-26, 2015

2 Aspen Art Museum

3 Wood Space Frame

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5 THE PLAYERS

6 OUTLINE THE BUILDING CONCEPT THE ARCHITECT S CONCEPT FOR THE ROOF 4 STRUCTURAL CONCEPTS FOR THE ROOF MOCK UPS MATERIAL STRENGTH TESTS FABRICATION ERECTION FINISHED BUILDING

7 THE BUILDING CONCEPT

8 Aspen, Colorado, USA

9 Snow load = ~ 90 psf (4.3 Kpa)

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11 Early rendering view up the main stair

12 Early rendering 3 rd floor terrace with wood space frame

13 Early rendering 3 rd floor terrace with wood space frame

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16 FLOOR PLANS BASEMENT GROUND LEVEL

17 FLOOR PLANS 2 ND FLOOR 3 RD FLOOR

18 3 RD FLOOR REFLECTED CEILING PLAN

19 100 ft x 100 ft on a 4 ft grid Max span = ~ 50ft 30.5m x 30.5m on a 1.2m grid Max span = ~ 15.5m

20 BUILDING SECTION Maximum 3 ft (91 cm) structural depth

21 THE ARCHITECT S CONCEPT

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24 STRUCTURAL CONCEPTS THREE ATTEMPTS AND FAILURES AND THE FINAL ROAD TO SUCCESS

25 1 ST CONCEPT: REINFORCED LAP SPLICES WITH DEHONIT COMPOSITE MATERIAL

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30 2 ND CONCEPT: KNIFE PLATES WITH TIGHT DRIVEN PINS

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37 3 RD CONCEPT: MICRO LAMINATIONS CROSSING AT JOINTS WITH NO HALF LAPS

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56 Hermann in Paris

57 Hermann in Paris

58 FINAL CONCEPT: HALF-LAPPED JOINTS KERTO CHORDS BIRCH PLYWOOD DIAGONALS FULL-THREAD SCREW CONNECTIONS

59 Half-lapped Joints KERTO BOTTOM CHORD LAYER 1

60 KERTO BOTTOM CHORD LAYER 2

61 BIRCH PLYWOOD WEB LAYER 1

62 BIRCH PLYWOOD WEB LAYER 2

63 KERTO TOP CHORD LAYER 1

64 KERTO TOP CHORD LAYER 2

65 Kerto S LVL Chords

66 Birch Plywood Diagonals WHY PLYWOOD?

67 BIRCH PLYWOOD LAYUP

68 mm laminations

69 (3.6 m plywood sheet length) BIRCH PLYWOOD WEB SPLICING PATTERN

70 Why Birch? Specific Gravity Bending Elastic Modulus Compression parallel to grain Compresion perpedicular to grain Shear Doug Fir Birch % increase 130% 134% 119% 115% 142% 174%

71 Connection concept (178 mm wide birch web) (172 mm wide x 133 mm deep Kerto S chord)

72 (172 mm wide x 133 mm deep Kerto S chord) (178 mm wide birch web)

73 4-SCREW JOINT

74 8-SCREW JOINT

75 12-SCREW JOINT

76 15-SCREW JOINT

77 (172 mm wide x 133 mm deep Kerto S chord) (178 mm wide birch web) 15-SCREW JOINT

78 TRUSS FABRICATION MODEL OVERVIEW

79 STRUCTURAL MODEL

80 DEFORMATIONS

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82 NORMAL FORCES TOP CHORD

83 NORMAL FORCES - WEBS

84 NORMAL FORCES BOTTOM CHORD

85 THE MOCK-UP

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96 TESTING

97 BIRCH PLYWOOD LAYUP

98 BIRCH PLYWOOD TEST SPECIMENS

99 BIRCH PLYWOOD TEST SPECIMENS

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104 SHOP FABRICATION

105 Kerto LVL Chords

106 Birch Plywood Diagonals

107 BIRCH PLYWOOD LAMINATIONS

108 THE LIBRARY

109 LAYOUT OF BIRCH PLYWOOD IN PREPARATION FOR GLUING

110 CLAMPING

111 BIRCH PLYWOOD WEB AFTER GLUING with PURBOND HB E452 single-component polyurethane adhesive Test Coupons

112 BIRCH PLYWOOD WEB PRODUCTION

113 BIRCH PLYWOOD WEBS READY TO SHIP (NOTE THICKENED WEBS AT COLUMN LOCATION)

114 SITE CONSTRUCTION

115 TOP OF THE THIRD FLOOR STRUCTURE, READY FOR WOOD SPACE FRAME INSTALLATION

116 SCAFFOLDING

117 Bottom Chords

118 BOTTOM CHORDS

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126 WEB SPLICES

127 COLUMN CONNECTION

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129 20,000 SCREWS -7 C (20 F)

130 8-SCREW CONNECTION (Top) 4-SCREW CONNECTION (Bottom)

131 15-SCREW CONNECTION

132 Quality Control

133 Screw connections

134 Screw connections

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143 Pulling the shores

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146 COMPLETED PROJECT

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154 WHAT WE LEARNED Design challenge centers on the nodes and connections.

155 WHAT WE LEARNED Wood is orthotropic: you must orient the wood fibers to your advantage. Engineered wood products with cross laminated layers were essential to the success of the project

156 WHAT WE LEARNED Hardwood is good

157 WHAT WE LEARNED Curved space frame members are beautiful, and yet at odds with their structural function.

158 WHAT WE LEARNED Knife plates and bolts are expensive and do not always take the best advantage of the wood properties

159 WHAT WE LEARNED Notches in half-lap joints dramatically reduce the strength of wood

160 WHAT WE LEARNED Screws create strong, redundant wood connections

161 WHAT WE LEARNED Preparation of precision virtual models for CNC fabrication is essential.

162 WHAT WE LEARNED The importance of early engagement of fabricators to participate in the design process cannot be overstated.

163 QUESTIONS?