GLASS FOLDED PLATE FACADE - TU Delft

G L A S S FOLDEDP L A T E FACADE

student//Eleftherios Siamopoulos1st mentor//Ate Snijder2nd mentor//Fred Veer

3rd mentor//Winfried MeijerTU Delft//June 2016

//INTRODUCTION

//RESEARCH OBJECTIVES

The main research objective is to explore the design possibilities of a glass folded plate facade, determine its technical qualities over other glass facade systems, and define the way it can be practically implemented.

Explore the mechanical properties of glass.Find the criteria to evaluate the structural integrity of a glass facade element.Find the criteria to evaluate the structural integrity of a glass facade system.Determine the structural advantages of folded plate against other systems.

Explore a range of folding patterns and their structural integrity.Determine the best connection principle for a glass folded plate facade.

Structurally validate the proposed facade system.Investigate ways to weatherproof the facade.

//RESEARCH STRUCTURE

Stage 1 - AnalysisStage 2 - Preliminary designStage 3 - Design of a suitable connectionStage 4 - Structural validationStage 5 - Design development

GLASSPROPERTIES

FOLDEDPLATE

STRUCTURES

GLASSFACADES

//ANALYSIS METHODOLOGY

//GLASS PROPERTIES

//MECHANICAL PROPERTIES OF GLASS

elastic range

plastic range

elastic range

plastic range

elastic range

<0.01mm, 45 MPa0.01mm, 40 MPa0.02mm, 35 MPa0.05mm, 30 MPa0.10mm, 25 MPa

>0.10mm, 20 MPa

Distribution of surface damage for: a) new glass, b) weathered glass, c) glass with inherent damage

Qualitative comparison of the stress-strain graphs for: glass, steel and wood

//PRESTRESSING GLASS - REDUNDANCY IN THE MATERIAL LEVEL

0.2d

0.2d

0.6d

0.2d

0.2d

0.6d

annealed glass

45 Mpa

heat-strengthened glass

70 MPa

Stre

ss C

ross

-sec

tio

nal

Dia

gram

s Fr

actu

re P

atte

rn

fully tempered glass

120 MPa

chemically strengthened glass

150 MPa

//LAMINATED GLASS - REDUNDANCY IN THE ELEMENT LEVEL

SGP (SentryGlas Plus)• tensile strength 300 MPa• 100 times more rigid sttructure than PVB• not affected by temperatures of 70oC• unaffected by load duration• 5 times higher tear strength than PVB• thinner laminate assemblies• safe laminates

PVB (Polyvinylbuteral)• tensile strength 20 MPa• high elasticity• affected by temperatures of 70oC• load duration dependent - prone to creep• average tear strength• safe laminates

CIP (Cast-in-place resin)

EVA (Ethylene vinylacetate)

Stress distribution diagram on a laminated glass cross-section:a) with no layer bondb) with flexible interlayer bondc) with stiff interlayer bond

//GLASS FACADES

//FACADE QUALITIES

• structural

• functional

• aesthetic

//GLASS FACADE SYSTEMS

Hierarchical Systems e.g. primary, secondary, tertiary

structure

Discrete-work Systemsseparation of vertical load-bearing

function and lateral bracing

Redundant Systemsstructures with residual

load-bearing capacity

//GLASS FACADE ELEMENTS

Planar (2D)

Linear (1D)

BendingShearCompressionBending

Pla

te E

lem

ents

Pan

e E

lem

ents

//CASE STUDIES ANALYSIS

Apple 5th Avenue Mark 2

• hierarchical system• bending and axial stiffness due to the thickness of the elements and the form of the system• elements acting as compres-sion plates and as panes loaded under bending • fin elements acting as beams loaded under bending• connection through laminated in fittings• redundancy addressed in the element level through lamina-tion

MAS Museum

• hierarchical system• bending and axial stiffness due to the form of the elements• elements acting as compres-sion plates and as panes loaded under bending • connection through structural adhesives• redundancy addressed in the system level by adding a steel beam

//FOLDED PLATE STRUCTURES

//STRUCTURAL ACTION OF FOLDED PLATE STRUCTURES

h

t b

� = ��8

� = ��

�� = �ℎ�12

2� = �

�� = 2�ℎ�12

� = ��8

� = ��

�� = �ℎ�12

2� = �

�� = 2�ℎ�12

Approximate equality of Second Moment of Area (I), between a folded plate-cross section and a rectan-gular cross section.

Simple folded plate system supported at the corners show c h a r a c t e r i s t i c a l l y large edge deforma-tions.

Inserting end plates to stiffen the struc-ture reduced deflec-tions to 6%. Due to the higher self weight, deflections in the mid-point along the ridge increase slightly.

Inserting a stiff di-aphragm between the supports, we can stiffen the system, significantly reducing midpoint deflections along the ridge

RR

R R

RR

Q

RR

//STRUCTURAL ACTION OF FOLDED PLATE STRUCTURES

Longitudinal and transverse action

In the transverse direction, the folded plate element behaves as a slab, transmitting the loads by the transverse bending of the plates, to their edges. In the direction of the primary span, this folded plate structure, behaves beam-like.

Slab action

In the transverse direction of the folded plate system, the plates act as a continuous beam or slab, with each slab act-ing as a support. The first moment diagram results when the folds are rigid, so the supports are fixed. The second moment diagram results when the folds are hinged, so the supports behave as hinges.

//PRELIMINARY DESIGN

Longitudinal Faceted Origami

//IDENTIFIED FOLDED PLATE PATTERNS

• structural depth

• Ix

• Iz

• surface mass

• elements number

• angles of elements

• total connection length

• connection numbers

• elements<jumbo sheets

//ANALYTICAL EVALUATION

Iz & Ix GraphsThe vertical and the horizontal pink line represent the Iz and Ix cross-section, respectively. The pink dashed lines show the values of the Iz and Ix, corresponding to points on the second moment of area diagrams.

Iz

Ixa b

c d

e f

Iz

Ix

Iz

Ix

Iz

Ix

Iz

Ix

Iz

Ix

2 DivisionStructural

Depth (m)

Ix (m4) Iz (m4)Efficiency

Ix &Iz(cm4/kg)

Mass (kg)

Elements Number

Angles of Elements

(o)

Total Connection Length (m)

Connections Number

Elements <

Jumbo Sheets

a s=32 y=0.10.0000160.0000600.000096

0.0000020.0000580.000098

1.921.87

31091/1/1/1/1/1/1/...

1.40-178.78

547.61/1/1/1/1/1/1/...

True

b s=32 y=0.20.0000600.0002360.000382

0.0000060.0002290.000387

7.056.86

33431/1/1/1/1/1/1/...

3.51-177.46

549.461/1/1/1/1/1/1/...

True

c s=32 y=0.30.0001340.0005290.000858

0.0000140.0005150.000869

14.4714.07

36591/1/1/1/1/1/1/...

2.94-174.91

552.341/1/1/1/1/1/1/...

True

d s=32 y=0.40.0002370.0009400.001525

0.0000250.0009140.001544

23.3122.66

40341/1/1/1/1/1/1/...

3.8-174.94

556.551/1/1/1/1/1/1/...

True

e s=32 y=0.50.0003710.0014690.002382

0.0000400.0014350.002413

32.9832.20

44551/1/1/1/1/1/1/...

3.07-174.15

561.681/1/1/1/1/1/1/...

True

f s=32 y=0.60.0005330.0021150.003430

0.0000570.0020650.003474

43.0842.07

49101/1/1/1/1/1/1/...

5.57-172.84

567.741/1/1/1/1/1/1/...

True

//RANDOM FACETED


Depth (m)


Ix(cm4/kg)

Mass (kg)

Elements Number

Angles of Elements

(o)


Connections Number

Elements <

Jumbo Sheets

ax=6z=6

y=0.10

0.0000380.000093

00.0000380.000093

1.241.24

3043 14445.17-89.66

340.9 144/84 True

bx=6z=6

y=0.20

0.0001480.000368

00.0001480.000368

4.794.79

3096 14445.67-88.67

342.36 144/84 True

cx=6z=6

y=0.30

0.0003320.000826

00.0003320.000826

10.4410.44

3183 14446.46-87.09

345.24 144/84 True

dx=6z=6

y=0.40

0.0005900.001468

00.0005900.001468

17.8817.88

3300 14447.49-85.01

349.56 144/84 True

ex=6z=6

y=0.50

0.0009220.002293

00.0009220.002293

26.7526.75

3446 14448.72-82.56

353.88 144/84 True

fx=6z=6

y=0.60

0.0013270.003301

00.0013270.003301

36.7036.70

3615 14450.08-79.84

359.64 144/84 True

Iz

Ixa b

c d

e f

Iz

Ix

Iz

Ix

Iz

Ix

Iz

Ix

Iz

Ix

//SQUARE FACETED

//EGGBOX FACETEDIz

Ixa b

c d

e f

Iz

Ix

Iz

Ix

Iz

Ix

Iz

Ix

Iz

Ix


Depth (m)


Ix & Iz(cm4/kg)

Mass (kg)

Elements Number

Angles of Elements

(o)


Connections Number

Elements <

Jumbo Sheets

ax=6z=6

yx=0.1

yz=0.4

0.0000930.0000930.000096

0.0014680.0014710.001502

2.8044.35

3317 14487.51-92.49

299.52 156/156 True

bx=6z=6

yx=0.2

yz=0.4

0.0003680.0003680.000375

0.0014680.0014690.001469

10.9343.64

3366 14485.11-94.89

302.64 156/156 True

cx=6z=6

yx=0.3

yz=0.4

0.0008260.0008260.000838

0.0014680.0014710.001502

23.9842.61

3446 14482.85-97.15

305.76 156/156 True

dx=6z=6

yx=0.4

yz=0.4

0.0014680.0014680.001483

0.0014680.0014690.001499

41.3041.31

3555 14480.80-99.20

312 156/156 True

ex=6z=6

yx=0.5

yz=0.4

0.0022930.0022930.002312

0.0014680.0014690.001509

62.1639.81

3690 14478.96-101.04

318.24 156/156 True

fx=6z=6

yx=0.6

yz=0.4

0.0033010.0033020.003324

0.0014680.0014680.001568

85.7938.14

3849 14477.35-102.65

327.6 156/156 True

//EGGBOX FACETED PHYSICAL MODEL

//CONNECTION DESIGN

θ

d

L

Μ max

F

F

Glued-in Plate Connection

Hinged Glued-in Plate Connection

Friction Connection

Glued Butt Joint

Riveted Steel Laminated Connection

Detailkm(kN)

kn(kN/mm2)

kv,i(kN/mm2)

kv,o(kN/mm2)

6.3.1 16 5 1 6

6.3.2 0.6 5 1 6

6.3.3.a 5 0.02 0.02 0.1

6.3.3.b 100 0.5 0.08 1

6.3.4.a 71 3.8 1.0 1.0

6.3.4.b 176 9.4 2.6 2.6

6.3.5 35 3.6 0.33 0.048

6.3.6 4100 220 86 86

//OVERVIEW OF CONNECTIONS

Detailα(-)

6.3.1 - Glued-in Plate Connection

0.622

6.3.2 - Hinged Glued-in Plate Connection

0.058

6.3.3.a - Friction Connection (EPDM)

0.340

6.3.3.b - Friction Connection (Kingersil)

0.911

6.3.4.a - Glued Butt Joint

(Eadh1

=1GPa)0.880

6.3.4.b - Glued Butt Joint (E

adh2=2.5GPa)

0.948

6.3.5 - Riveted Steel Laminated Connection

0.783

6.3.6 - Glass Joint0.998

5mm heat strengthened glass

2x0.9mm SG+ interlayer

PURE sheet 1mm

stainless steel rivet

HY70 epoxy-grout



PURE sheet 1mm


HY70 epoxy-grout


aluminum spacer



1mm PURE sheet

aluminum spacer

HY70 epoxy-grout




1mm PURE sheet


HY70 epoxy-grout




PURE sheet 1mm


HY70 epoxy-grout



PURE sheet 1mm


HY70 epoxy-grout


aluminum spacer



1mm PURE sheet

aluminum spacer

HY70 epoxy-grout




1mm PURE sheet


HY70 epoxy-grout


//CONNECTION PRELIMINARY DESIGN

B - Solid Plate

A - IGU Plate

Specimen Fmax

(N) dL at Fmax

(mm)

O1 4636 11.20

O2 4709 11.77

O3 4431 10.55

O4 4840 12.82

average 4654 -

Specimen Fmax

(N) dL at Fmax

(mm)

S1 4773 11.90

S2 4198 10.35

S3 4458 11.24

S4 4450 10.90

average 4470 -

25.5mm

125mm

30mm

95mm

6mm

//PURE TESTING

//PURE TO PURE BOLTED CONNECTION TESTING

0

200

400

600

800

1000

1200

1400

0 5 10 15 20

Stan

dar

d f

orc

e [N

]

Strain [mm]

PURE to PURE Bolted Connection

W1 W2 W3 W4

PURE to PURE Bolted Connection Variations a) adhesive connection with A-K540 structural adhesiveb) friction connection with 1mm thick stainless steel friction fittings


0.89mm SG+ interlayer

1.5mm PURE sheet

A-K450 structural adhesive

M5 stainless steel bolt


0.89mm SG+ interlayer

1.5mm PURE sheet

1mm stainless steel friction fitting

M5 stainless steel bolt

a

b

//PURE TO GLASS LAMINATION TESTING

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

"A" PURE Connection - Sheet

A1 A2 A3 A4

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

"B" PURE Connection - Sanded

B1 B2 B3 B4

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

”D” PURE Connection - Ø3mm

D1 D2 D3 D4

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

”C” PURE Connection - Interlocking

C1 C2 C3 C4

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

”E” PURE Connection - Ø8mm

E1 E2 E3 E4

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dard

forc

e [N

]

Strain [mm]

”F” PURE Connection - Ø6mm

F1 F2 F3 F4

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

”G” PURE Connection - Ø12mm

G1 G2 G3 G4

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

”H” PURE Connection - Ø3mm Pyramidal

H1 H2 H3 H4 H5

0

500

1000

1500

2000

2500

3000

0 2 4 6 8 10 12 14 16

Stan

dar

d f

orc

e [N

]

Strain [mm]

”I” PURE Connection - Ø3,6,9mm

I1 I2 I3 I4 I5

//PURE JOINT DETAIL


0.9/1.5/0.5mm SG+ sheet

1.5mm PURE sheet

2mm thick stainless steel spacer

HY-70 epoxy-grout

1mm thick stainlesssteel friction fittingM5 stainless steel bolt

θd

L

Μmax

F

F

0

200

400

600

800

1000

1200

1400

1600

1800

2000

00 .050 .1 0.15 0.20 .250 .3

Mom

ent

[Nm

/m]

Rotation [rad]

"P" PURE Joint

P1 P2 P3 P4

1100

0.095 0.0960.088

//PURE JOINT BENDING TESTING

Force - Elongation Table for Specimens P1, P3, P4 for a F=2F

max/3=1100N

Specimen F1100

(N) dL at F1100

(mm)

P1 1100 7.71

P3 1100 7.05

P4 1100 7.63

average 1100 7.46

km=M/θ=11.38kN/rad

//PURE JOINT BENDING TESTING

Detailα(-)

6.3.1 - Glued-in Plate Connection 0.6226.3.2 - Hinged Glued-in Plate Connection 0.058

6.3.3.a - Friction Connection (EPDM) 0.3406.3.3.b - Friction Connection (Kingersil) 0.9116.3.4.a - Glued Butt Joint (E

adh1=1GPa) 0.880

6.3.4.b - Glued Butt Joint (Eadh2

=2.5GPa) 0.9486.3.5 - Riveted Steel Laminated Connection 0.783

6.3.6 - Glass Joint 0.9986.6.1 - PURE Joint 0.549

Analysis 1E=3286N/mm2t=6.28mm

Analysis 3E=3350N/mm2t=7mm



Analysis 2 E=3286N/mm2t=7mm




d=11.4mm

d=8.10mm

d=7.33mm

d=7.47mm

d=8.26mm

d=7.75mm

d=7.43mm

d=7.46mm

}

}

}

}

}

}

}

}

//PURE JOINT SUPPORT ACTION

Μmax

Q

Q

Μmax(?)

Μmax(?)

Q

Μmax

0.14MPa

12MPa

-2.80MPa

10.70MPa

-13.80MPa

5.74MPa

//STRUCTURAL ANALYSIS

+1.2x 1.5x

+1.0x 1.0x

+1.0x 1.0x

Service Limit State

Service Limit State

Ultimate Limit State

//LOADCASES

MAX displacement +

MAX stresses

MAX displacement<h/300(=36.6mm)

MAX stresses<σmax

A//Intact Facade System Scenario

B//Total Failure of Facade Element Scenario

//SAFETY & DESIGN

Material Level (micro)

Material Safety FactorMAX tensile strength

1.5

Pre-stressing Glassheat-strengthened glass - 52MPafully tempered glass - 88MPa

Minimize Superficial Flawscontrolled processing

Lamination of Glass PanelsSG+

MAX tensile strength x 1.1

Protection of Edgespolishing

structural stainless steel spacer

Flexible Connectionas hinged connection as possible

Bending Stiffness of Facadefolded plate structure

Redundancyhyper-static structurealternative load-paths

Structural Schemestructure under compression

Element Level (meso) System Level (macro)

Increase RedundancyReduce Damage Sensitivity

//FINITE ELEMENT MODEL

A

D

C

B

X

ZY

X

ZY

black meshplate mesh and glass

propertiesblack dot mesh

edge mesh and stainless steel spacer properties

magenta meshconnection mesh and con-

nection properties

Tx, Ty, Tz, Rx, Ry, Rz Tx, Ty, Rx, Ry, Rz Tx, Rx, Ry, Rz Tx, Ty

vertical own load

perpendicularwind load

vertical own load

perpendicularwind load

Total Failure of Facade Element

LoadsBoundary ConditionsPlate - Spacer - Connection Meshing

//ULS POSITIVE WINDLOAD- INTACT - TENSILE STRESSES

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

σmax =30.30MPa(=24.55MPa)

σmax=31.55MPa(=26.40MPa)

//ULS POSITIVE WINDLOAD - INTACT - COMPRESSIVE STRESSES

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

σmax=-64.70MPa σmax=-72.05MPa

//SLS POSITIVE WINDLOAD - TOTAL ELEMENT FAILURE - TENSILE STRESSES

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

σmax =27.65MPa(=20.88MPa)

σmax=35.05MPa(=28.00MPa)

//SLS POSITIVE WINDLOAD - TOTAL ELEMENT FAILURE - COMPRESSIVE STRESSES

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

Con

tour L

evel Results

Vec

tor R

esults

Num

eric R

esults

σmax=-52.15MPa σmax=-76.85MPa

//SLS - DISPLACEMENTS

Intact Deformation Results - Positive Wind load Total Element Failure Deformation Results - Positive Wind load

Total Element Failure Deformation Results - Negative Wind loadIntact Deformation Results - Negative Windload

d=7.84mm d=11.2mm

d=5.63mm d=6.84mm

//COMPARISON OF FACADE SYSTEMS

Comparison

Displacement [mm]

12.90 1.57 10.80

Max S1 bottom surface [MPa]

+14.20 +4.34+30.30

(+24.55)

Max S1 top surface [MPa]

+11.60 +3.69+31.55

(+26.40)

Max S3 bottom surface [MPa]

-17.90 -10.90 -64.70

Max S1 top surface [MPa]

-14.90 -14.20 -72.05

Redundancy[Boolean]

NO NO YES

Manufacturability[-]

+ - ++

Cost[-]

+ ++ -

Insulation[-]

- + ++

Form Finding Potential[-]

- + ++

//DESIGN DEVELOPMENT

6mm heat-strengthened glass pane

0.9mm SG+ sheet 0.9mm SG+ sheet 6mm heat-strengthened glass pane

6mm heat-strengthened glass pane

1.5mm perforated PURE sheet

0.9mm SG+ sheet

1.5mm perforated PURE sheet

0.9mm SG+ sheet 2mm thick stainless steel structural spacer

0.9mm SG+ sheet 1.5mm SG+ sheet 6mm heat-strengthenedglass pane

//EXPLODED PLATE DETAIL

//TOP FACADE FOUNDATION DETAILarmed concrete floor slab100mm rockwool insulation20mm thick facadecladding ceramic tiles

extruded aluminum profileM6 steel bolt

extruded aluminumvertical beam

M6 steel bolt125x80mm steel U-profile

slotted holeM12 steel bolt

M15 steel reinforcementwith treads

100mm thick plasticsetting blockcustom made steel profilewaterproofing membrane

20mm thick ceramic facade cladding tile

extruded aluminum beam 5mm thick custom made steel U-profile3mm thick neoprene spacer

60x45x3mm glued-in steel U-profilecompressive insulation

cavi

ty fi

lled

with

rock

woo

l

cavity filled with rockwool

964954

5060

4130

15

4130

15

100 50 15

armed concrete floor slab100mm rockwool insulation

20mm thick facadecladding ceramic tiles

extruded aluminum profileM6 steel bolt

extruded aluminumvertical beam

M6 steel bolt125x80mm steel U-profile

slotted holeM12 steel bolt

cavi

ty fi

lled

with

rock

woo

l M15 steel reinforcementwith treads

100mm thick plasticsetting block

custom made steel profile

cavity filled with rockwool

waterproofing membrane

M12 steel nut and washer

60x2mm stainless steel tube

20mm thick ceramic floor tile

10mm thick cement based grout

80x60x5mm steel U-profile

964

190 100 50 15

154

3015

//BOTTOM FACADE FOUNDATION DETAIL

Conclusions Recommendations

//CONCLUSIONS & RECOMMENDATIONS

1//It is possible to design and construct a self-supported glass folded plate facade, where the skin and the structure are integrated.

2//The Eggbox folded plate pattern is the most adequate for such a structure, as its folds make it very stiff.

3//The PURE sheet joint, is adequate for such a structure due to its semi-rigid behaviour. Its perforations, make it more transparent.

4//A 24mm thick heat-strengthened glass as-sembly is more than enough to take the loads imposed on the facade, even in the case of an element’s failure - redundant structure.

5//Some stress concentrations cannot be avoided.

6//Easier manufacture, less cost, and high po-tential for climate control system’s integration.

1//Investigation of more folded plate patterns and develop a tool for their structural optimi-zation.

2//Develop the proposed connection in terms of the connection’s strength and its local sup-port conditions.

3//Focus on the sustainability aspects of the facade.

thank you!

Documents

GLASS FOLDED PLATE FACADE - TU Delft