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ADVANCED DESIGN DESIGN OF GLASS GLASS STRUCTURES Lecture L7 / E3_ME Design of glass balustrade Martina Eliášová European Erasmus Mundus Master Course
Sustainable Constructions under Natural Hazards and Catastrophic Events 520121-1-2011-1-CZ-ERA 520121-1-2011-1-CZ-ERA MUNDUS-EMMC
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Objectives of the lecture Objectives Monolithic glass SLS Monolithic glass ULS Laminated glass SLS Laminated glass ULS
•
Design of glass balustrade
Worked example Design a glass balustrade in a department store as a cantilever with height h = 1100mm. Glass panels are continuously clamped and design load is q . Check the ULS and SLS for convenient type of glas s for a) single layered glass, b) laminated glass (neglect the effect of the interlayer). q
loading q = a 1,5 kN/m glass thickness: t = 8, 10, 12, 15, 19, 25 mm h
design value of glass strength: • float glass
f g,d = 18 MPa
• heat strengthened
f g,d = 25 MPa
• toughened glass
f g,d = 50 MPa
2
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Monolithic glass - SLS Objectives
1. SLS
Monolithic glass SLS
• limit for deformation
Monolithic glass ULS
h
lim
Laminated glass SLS
2h 200
11 mm
• load action – equivalent force from the length of 1.0m
Laminated glass ULS
P Ed
1m
q 1 ,0m
• horizontal deflection of the balustrade
P Ed h 3 EI y
3
t min = …..
lim 11 mm
• one equation for one unknown t t
y
E 70 000 MPa
I y
1 12
3
bt
b = 1,0m
• choose thickness of the glass t t min 3
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Monolithic glass - ULS Objectives
1. ULS
Monolithic glass SLS
• moment at the fixed edge
Monolithic glass ULS
M Ed
h
Laminated glass SLS
P h Ed
• tensile stress from the load action
Laminated glass ULS
t , Ed
M Ed
type of glass, res. f g,d
W y
t
y b = 1,0m
W y
1 6
2
b t
4
Laminated glass - SLS Objectives
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1. SLS
Monolithic glass SLS Monolithic glass ULS
• double layered glass pane with the same thickness 2x t1
h
• safety design no composite action of interlayer (GPVB = 0 ): two glass pane without any connection
Laminated glass SLS Laminated glass ULS
• horizontal deflection of both pane have to be equal
1m
P Ed h
3
3 E 2 I y ,1
lim 11 mm
• moment of inertia of one glass pane
t 1
y b = 1,0m
t 1
I y ,
1
1 12
3
bt
1
• one equation for one unknown t 1 (thickness of each glass pane)
• choose thickness of the glass t 1
t 1,min 5
Laminated glass - ULS Objectives
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1. ULS
Monolithic glass SLS
• moment at the fixed edge
Monolithic glass ULS
M Ed
h
Laminated glass SLS
P h Ed
• tensile stress from the load action at one glass pane
Laminated glass ULS
1
t , Ed
2
M Ed
type of glass, res. f g,d
W y ,
1
y b = 1,0m
t 1
W y ,
1
1 6
2
b t
1
6
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Thank you for your kind attention
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