ADVANCED DESIGN OF GLASS STRUCTURES

Design of glass fin

Viorel Ungureanu

European Erasmus Mundus Master Course Sustainable Constructions

under Natural Hazards and Catastrophic Events 520121-1-2011-1-CZ-ERA MUNDUS-EMMC

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Objectives of the lecture • Design of glass fin Assess glass fin of the facade – see figure. It is simply supported and suspended from its top support. It is bolted to the inside face of a glass facade and silicone seals provide continuous attachment between the edge of the fin and facade. It is assumed that for short-term gust loads the silicone seals are capable of providing lateral restraint to the edge of fin. It is also assumed that the low modulus of silicone does not permit any T-beam action between the fin and the facade.

L = c1 6000 mm b = 500 mm B = c2 1500 mm t = 16 mm wind load w = 1,0 kN/m2 unit weight 2500 kg/m3

L

b

B

tension strength of glass short-term load long-term load float glass (t = 10mm) 28,0 MPa 7,0 MPa toughened glass 59,0 MPa 35,0 MPa

Objectives

Short term load action

Long term load action

Lateral torsional buckling

Deformation

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Short term load action 1. Moment (design value) – simple check

• Wind load w = 1,0 kN/m2

• Load width B = c2 1500 mm

2. Section modulus

3. Short term load action

168

1 32 tELwM kFEd

Objectives

Short term load action

Long term load action

Lateral torsional buckling

Deformation

5,1F

mkNBwwk

2

61 btWy y b

t

dy

Ed fWM

- decision about the type of glass

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Long term load action 4. Axial load in the fin - self weight for = 25kN/m3

5. Long term load action from self weight

LBtLbtN FEd

Objectives

Short term load action

Long term load action

Lateral torsional buckling

Deformation

dfin

Ed fAN

- depends on the type of glass

glass fin glass facade

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Lateral torsional buckling 6. Lateral torsional buckling of the glass fin according to the Australian

standard

• La = length of the beam

• d = b …. height of the glass fin

• Iz moment of inertia

• G = 28 700MPa – shear modulus of elasticity

• J = It …torsional moment of inertia

• yh = 250mm …. location above the neutral axis of the loading point, positive or negative values for suction and compression

• y0 = 250mm …. distance of the restraints from neutral axis

Objectives

Short term load action

Long term load action

Lateral torsional buckling

Deformation

h

za

CR yy

GJydEILM

0

20

22

24

3

121 tbI z 3

31 tbI t

6

Deformation 7. Check - simple approach

8. Vertical deformation

9. Vibration

Objectives

Short term load action

Long term load action

Lateral torsional buckling

Deformation

5003845

lim

4 LEILw

y

k

3

121 btI y

71,MM cr

Ed

Hzf 516

7

Thank you for your attention

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