How to Stand Out with Tensile Structures...fritted single layer ETFE foil membrane on bronze frame, arch ~ w/ catenary edges ~ UN Porte Cochere NYC 2009 60’ x 200’, polycarb sidewalls,

How to Stand Out with Tensile Structures

Nic Goldsmith

2018 IFAI Expo Dallas Oct 15-18

Standout = one that is prominent or conspicuous because of excellence

fabric structures

The U.S./Canadian fabric structures market experienced growth of 3.5 percent in 2016 and grew to 4.1 percent in 2017.

• There is a continuing increase in demand for engineered structures

• Increase of fabric structure applications—auto dealerships, outdoor sporting events

• More infrastructure projects including stadiums, shade structures, bus stops and other transportation canopies

• Emergency response structures have increased

• Quality and performance has improved ~ coatings have developed

Based on IFAI state of Industry 2017, 2018

1. types of fabric structures ~ applications

a. structurePole structures (tensile)Frame structuresArch structures

b. climateEnclosed – possibly heated/cooledOpen sides – canopies shade/rain

c. permanent/temporaryRetractable – operableDeployable - quick installDemountable – seasonal

2. design process ~ form finding, analysis, CAD

3. manufacturing ~ materials, details

4. installation

Based on IFAI IAA Categories 1,2: tensile structures less than 24,000 sq. ft.

a. structure ~ pole supported freeform perimeter ~ Premium Outlets, Las Vegas 2003PVC fabric, cone patterns with rings, translucent w/ up lighting, permanent

pole ~ separated cable and fabric ~ Finnish Chancery Washington DC 1998cable braced columns for thin steel effect, PVC fabric, nautical rigging, permanent

mast supported ~ 80’ x 100’ summer theater for Hudson Valley Shakespeare 2018, chapiteau concept, seasonal installation, permanent foundations, no crane required, demountable

frame ~ Bard Canopy, Bard College, Rhinebeck NY 2004 covered walkway, open sides, hypar form, no cables, permanent

freeform frame ~ seaman pavilions, Millersburg OH 2014PVC fabric, edge catenaries to frame, translucent & opaque colored fabric, permanent

rectangular frame ~ 1025 Fifth Ave NYC 2011fritted single layer ETFE foil membrane on bronze frame,

arch ~ w/ catenary edges ~ UN Porte Cochere NYC 2009 60’ x 200’, polycarb sidewalls, PTFE & silicone glass fabric, vehicular & pedestrian entries, serpentine trusses fabricated in sections, 5 year lifespan

arch gridshell ~ wood or steel ~ Empire City Casino Yonkers NY 2013 fabric or ETFE foil covering, considerable steel framing, good snow loading, permanent only

b. climate enclosed ~ framed box structure, closed sides, entries at few points, triangulated frame, no snow loads, lighting as design feature, temporary

climate enclosed frame ~ Nike 2012 Olympics, 54% translucent pvc fabric, demountable

climate open air ~ framed tensile fabric walls and canopy ~ Alvin Ailey NYC 2005steel frame, PTFE glass fabric

c. retractable roof ~ Tenara fabric, frame & beams to be powder coated alu, synchronized drive gear on each beam, designed for 100 mph wind, 3min install

Juvia Hotel, Miami BeachDining terrace for 60

c. deployable ~ air beam – low pressure, temporary installations, 5psi pressure, cycled inflation no snow loading

deployable ~ high pressure - air tubes with stiffening membranes – LANMAS ~ US Army, Natick 30 min install, 30 psi pressure with braided Kevlar with urethane bladder, no metal, $$$

deployable ~ air inflated - Dyson D-Tour traveling exhibit 2005tetrahedral frame supports air structure w/ air locks, deployable w/ 4 day setup

deployable ~ external frame with tensioned sidewalls ~ Cadillac ExcelerationPavilion ’96 ~ deployable 8,000 sq ft frame folds from ground with one crane pick, 1 day setup, black out PVC fabric, sidewalls roll up in sections

2. design process

basic design concepts ~ structure: membrane support types

A. frame B. cable & strut

C. cable net D. pneumatic

traditional formfinding ~ physical modeling: soap film, patterning, photo-elastic, wind tunnel, snow

hand sketches

process ~ hand sketch, Rhino modeling, Acad drawings, built project ~ Gicsa Puerta Vallarta

design process with physical models ~ sketches, formfinding, CAD details

finite element analysis: non linear stiffness (NDN), force density (EZ Form, ix Cube), dynamic relaxation (tensyl suite, inTens)

3. manufacturing

a. Materials (Fabric Specific)b. Supply Chainc. Tolerancesd. Machines / Operator Training

coated fabrics foils insulated fabrics mesh fabrics, nets

pvc/poly, ptfe/glass etfe, ectfe nanogel w/ptfe, pvc/poly, ptfe/glass

silicone/glass, eptfe, hdpe foam pvc

r value 1-3 r value 1.9 - 5 r value 3 - 12 none

0 – 64% luminous clear, frit 40% - 98% 0 – 3.5% luminous based on opening

1 – 2 layers 2-5 layers (pillow) 3 layer, 1 layer 1 layer

warranty 10 – 15 10 10 – 15 10 - 15

lifespan 15 – 30+ 30+ 15 – 30+

possible materials

manufacturing ~ details

membrane plate connections ~architectural gradedetails

membrane plate connections ~ commercial grade

site joints – architectural gradeclamping, cable joints for PVC, PTFE, diablo connection

site joints – commercial gradeZipper, grommets, dutch lacing, shackle w/flap, rope lace on guides

mast tops

mast bases – architectural gradetapered masts,

mast bases – commercial gradesimple pin, minimal base plate

branched supports - architectural grade only

cable tie downs – architectural grade plinths, pile caps

tie downs – commercial grade

oculus or rings

struts / spars

humpssurfaces that are continuous

keder frame extrusions

cable fittings

4. installation

installation

a. Planning Sequence – one of the biggest losses on jobsites can be waiting because of poor planning

b. Having qualified people to install

c. Proper appearance of installed fabric

d. Training – including OSHA requirements

the small the big the complex

Fabric Structures as integration of:

1. structure2. form3. climate 4. lighting5. acoustics6. water collection/drainage

The more you can incorporate these elements, the more you will stand out

Your project now becomes more than a tent, it is landscape, infrastructure, etc.

Comfortable space achieved by

functional ETFE film

Hiroshi ARUGA AGC CO., LTD.

15th Oct 2018 in IFAI

Classification for comfortable Space made by ETFE film

Request Corresponding term Today Contents

Safety ・Weather durability

・Tensile Strength at

10% Strain

・MIT bending

New ETFE film

・High tensile Strength

at 10% Strain

・High Clarity

(Haze 2% )

・High resistance to

MIT bending test

Clarity

(as Glass)

・low haze, not milky

Not so hot

Not so bright

light & heat control

・SC (S.H.G.C)

・U value

・UV transmittance

・Visible transmittance

Weather Durability

・UV blocking

・NIR absorbing

・Silver print

・Color

Impressive ・Impressive print ・Digital print by inkjet

ETFE is copolymer resin of ethylene and tetrafluoroethylene.

C

H

H F

C C C

H

H

F

F

F

nm

ethylene tetrafluoroethylene

C

R

R

C

R

Ro

Third monomer (slight amount)

Component of the ETFE

Resin maker can improve modulus, MIT bending performance,

tear strength, and clarity by changing the ratio of m, n, o.

Copolymerize

Kiyotaka Arai, Atsushi Funaki, Suttinun Phongtamrug and Kohji Tashiro. Influence of side branch on the elastic

modulus of ethylene-tetrafluoroethylene terpolymers . Polymer 50(2009),4612-4617

THE and TFE copolymer

ethylene tetrafluoroethylene

Third monomer(slight)

terpolymer

Figure 1. TFE content dependence of the storage

modulus of ETFE copolymer &

terpolymer samples measured at 23°C.

Composition to get the maximum modulus

Maximum

modulus

point

Table.1 Mechanical and Optical properties of 250μm ETFE film

Conventional New

ETFE resin D A E

Melting Point (°C) 268 255 230

Tensile Strength at 10%

Strain (MPa) at 23°C24 22 23 25

Tear strength (N/mm) 230 200 200 220

Haze(%) : Milky 12 11 6 2

MIT bending times to break

（×1000）

T=1mm R=3mm 20 300 250 200


Conventional New

ETFE resin D A E



Strain (MPa) at 23°C24 22 23 25


Haze(%) : Milky 12 11 6 2


（×1000）

T=1mm R=3mm 20 300 250 200By changing film

molding method

By changing

composition of resin

2% Haze

(New Item)

11% Haze

(current)

250μm ETFE Film Transparency

6% Haze

(current)


Conventional New

ETFE resin D A E



Strain (MPa) at 23°C24 22 23 25


Haze(%) : Milky 12 11 6 2


（×1000）

T=1mm R=3mm 20 300 250 200

Fig. sketch of the MIT examination

MIT Bending Test (ASTM D2196)

bending times to breakPlunger

Test pieceBending

mechanism

MIT bending test

R=1 or 3mm

Bending test represents to the resistance to film fluttering.

Essential item for safety


Conventional New

ETFE resin D A E



Strain (MPa) at 23°C24 22 23 25


Haze(%) : Milky 12 11 6 2


（×1000）

T=1mm R=3mm 20 300 250 200





10% Strain

・MIT bending

ETFE Film Grade


10% Strain

・High Clarity

(Haze 2% )

・MIT bending testClarity

(as Glass)


Not so hot

Not so bright


・SC (S.H.G.C)

・U value

・UV transmittance


Weather Durability

・UV blocking

・NIR absorbing

・Color

・Silver print

Impressionable ・Impressionable print ・Digital print

Performance of ETFE film exposed to

outdoor for 30 years in Japan（～1987）

60μm normal film2018

measured,

30 years later

Initial

(1987)

Transmittance 92.2 % 94.0%

Strength to break 55 MPa 60MPa

Elongation to break 355 % 406%

Tear Strength 172 N/mm 214 N/mm

2018

Mr. Yasuda wants to

use it for

another thirty years.

2018

0

10

20

30

40

50

60

70

80

90

100

300 500 700 900 1100

tran

smit

tance

( %

)

wavelength （nm）

initial5 years later10 years later

0

10

20

30

40

50

60

70

80

90

100

300 600 900 1200 1500 1800 2100

tran

smit

tance

( %

)

wavelength （nm）

initial5 years later10 years larer

Optical change of outdoor exposure in Florida

UV blocking ETFE (200μm) NIR absorbing ETFE(200μm)

10 years passed in Florida, Optical change is slight and stable.

16

18

20

22

24

26

0 2 4 6 8 10 12

Str

ength

at1

0%

str

ain

( M

Pa

)

outdoor exposure years in Florida

Strength at 10% strain

200WT 250TB200UVC 200NJ200NJ Print 200IRC200ME AVERAGE

150

170

190

210

230

250

0 2 4 6 8 10 12

Tea

r S

tren

gth

(

N/m

m )

outdoor exposure years in Florida

Tear Strength

200WT 250TB200UVC 200NJ200NJ Print 200IRC200ME AVERAGE

98%

102%

Mechanical change of outdoor exposure in Florida

10 year Passed in Florida , Both index keep initial value

Reason why the optical and mechanical properties do not change for long time

Filer

water glass

（silica）

・ ETFE resin has good weather durability.

・ In functional ETFE film, Silica coating filler are used

Filler CeO ZnO TiO2 LaB6 ATO CWO

Silica coating layer can prevent the chemical reaction between filler

and ETFE. Filler and ETFE are stable for a long time.

Silica

coating

layer

Colored ETFE film

All Color pigments have silica coating layer

Gravure printing film

silver aluminum white Titanium dioxide.

Visible light Solar light SC value

(4mm

Glass =1)Transm

ittance

Reflec

tion

Transm

ittance

Reflec

tion

High Reflection

Silver ink on ETFE17 57 17 58 --

250NJ( ETFE) 90.8 7.6 92.6 6.5 --

90% area print 24 52 24 53 0.35

Table.2 Light and heat propeties of this printed ETFE film

How about visible light transmittance? SC ?

[condition]

90% area print with high reflection

silver ink on 250μm ETFE

Tv and SC depend on ink species and printed area ratio .

Bird‘s nest in Beijing used ETFE print film（～ 2007）

This film is still shiny now,

but how long can this film keep shiny ?

71

10.97

0.94

0.880.84

0.82 0.75

0.5

0.6

0.7

0.8

0.9

1

0 3000 6000 9000 12000 15000Re

tention

of re

flecta

nce (

-)

SWM test hours（H)

Retention of reflectance by accelerated weathering test

10.98

0.92

0.890.82

0.81

0.79

0.5

0.6

0.7

0.8

0.9

1

0 2 4 6 8 10 12Rete

ntion

of re

flecta

nce (

-)

exposure years (Kochi, Japan)

Retention of reflectance by actual exposure test

( Kochi ,

Japan )

1 year outdoor exposure = 1000H in accelerated test . (Relationship)

In 2022 (15 years from 2007), 75% reflectance will keep, shiny !

Actual exposure test and

accelerated weathering test (SWM) Single layer & Back exposure

After

15years

outdoor

2007～

Weather durability test of Silver print

in accelerated test machine

S.W.M.

For more than 10 years request, only 10,8,9 can be used.

Performance is different depending on film makers and fabricators

Tv and SC value of functional ETFE film

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0 20 40 60 80 100

SC

val

ue

Transmittance of visible light ( % )

silver print

White print

White Color

Standard ETFE

UV blocking

NIR absorbing

Bright & Cool





10% Strain

・MIT bending

ETFE Film Grade


10% Strain

・High Clarity

(Haze 2% )

・MIT bending testClarity

(as Glass)


Not so hot

Not so bright


・SC (S.H.G.C)

・U value

・UV transmittance


Weather Durability

・UV blocking

・NIR absorbing

・Silver print

・Color

Impressionable ・Impressionable print ・Digital print by inkjet

Inkjet print to ETFE

Color fading , ink peeling off.

UV cured acrylic ink

250NJ (ETFE)

UV cured acrylic ink：

250UVC(ETFE)

Primer 3μm coating

Inkjet improvement of retention of color and

ink adhesion after weathering test (S.W.M)

S.W.M.

initialAfter S.W.M. 10000H

（= Outdoor 10 years test)After S.W.M. 10000H

（= Outdoor 10 years test)

Development of weather resistance

for over 20 years

・New ink using inorganic pigment ・New ink jet device

Weathering test in progress..

Next task for comfortable Space

Request Today Contents Developing new ETFE item

Safety ・Tensile Strength

at 10% Strain

・Thickness 500μm

・Glass-cloth lamination

membrane

Clarity ・low haze 2%

Not so hot

Not so

bright

・UV blocking

・NIR absorbing

・Silver print

・Color

・Sputtering Technology

Transparent IR reflection

Transparent low E

(Film makers & Fabricators)

Impression

able print

・Digital print for

10 years.

・Digital print technology for

over 20 years outdoor.

We want to make ETFE membrane market to grow

with fabricators and architects.

Documents

How to Stand Out with Tensile Structures...fritted single layer ETFE foil membrane on bronze frame, arch ~ w/ catenary edges ~ UN Porte Cochere NYC 2009 60’ x 200’, polycarb sidewalls,