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EN 1995-1-1Design of timber structures
EC 5-1-1 Design of Timber Structures DIN 1052
EC 5-1-1 Design of Timber Structures
General conceptGeneral concept
EC 5-1-1 Design of Timber Structures
Design situationsDesign situations
• Permanent situation Permanent situation (after erection of the (after erection of the structure)structure)
EC 5-1-1 Design of Timber Structures
• temporary situation temporary situation (during erection)(during erection)
Design situationsDesign situations
EC 5-1-1 Design of Timber Structures
• Accidential situation Accidential situation (impact, fire)(impact, fire)
Design situationsDesign situations
EC 5-1-1 Design of Timber Structures
Limit statesLimit states
• Ultimate limit statesUltimate limit states
• Serviceability limit statesServiceability limit states
For all design situations the limit states shall For all design situations the limit states shall not be exceeded. not be exceeded.
EC 5-1-1 Design of Timber Structures
• Characteristic Actions according Characteristic Actions according to EN 1991to EN 1991
GGkk e.g. self-weighte.g. self-weight
QQkk e.g. wind, snow, traffice.g. wind, snow, traffic
AAkk e.g. impacte.g. impact
ActionsActions
EC 5-1-1 Design of Timber Structures
Ultimate limit stateUltimate limit state
Design values of actionsDesign values of actionsBasic combination:Basic combination:G,j G,j GGk,jk,j + + Q,1 Q,1 QQk,1k,1 + + Q,i Q,i 0,i 0,i QQk,ik,i
e.g. 1,35e.g. 1,35 GGkk + + 1,51,5 WWkk + + 1,51,5 0,5 0,5 SSkk
simplified:simplified:
Most unfavourable variable action: Most unfavourable variable action: G,j G,j GGk,jk,j + + Q1 Q1 QQk,1k,1 1,351,35 GGkk + + 1,51,5 WWkk
All unfavourable variable actions:All unfavourable variable actions:G,j G,j G Gk,jk,j + 1,35 + 1,35 Q Qk,ik,i 1,351,35 ( (GGkk + W + Wkk + S + Skk))
EC 5-1-1 Design of Timber Structures Design and calculation principles
From a statistic point of view it´s unlikely that all actions/loads act at the sametime with their fully values.
0 combination coefficient (in fundamental design situations)
1 frequent coefficient (in accidential design situations and servicability
calculations)
2 quasi-permanent coefficient (in servicability calculations)
Principle rule:
G K Q,1 K ,1 0,i Q,i K ,ii 2
G Q Q
Coefficient for represantative values of actions (for exact national data see: National Applience Documents)
Use of 0 from the second variable action/load.
Design values of actions; coefficient for representative values of actions:
EC 5-1-1 Design of Timber Structures
Combination factorsCombination factors
EC 5-1-1 Design of Timber Structures
Combination factors Combination factors
ActionAction 00 11 22
Domestic residential areasDomestic residential areas 0,70,7 0,50,5 0,30,3
Congregation areasCongregation areas 0,70,7 0,70,7 0,60,6
Storage areasStorage areas 1,01,0 0,90,9 0,80,8
WindWind 0,60,6 0,50,5 0,00,0
Snow (Snow ( 1000 m) 1000 m) 0,50,5 0,20,2 0,00,0
EC 5-1-1 Design of Timber Structures
Partial safety factors for actions Partial safety factors for actions (EN 1990)(EN 1990)
ActionAction permanentpermanent variablevariable
favourablefavourable GG = 1,0 = 1,0 QQ = 0 = 0
unfavourableunfavourable GG = 1,35 = 1,35 QQ = 1,5 = 1,5
13
Ed
Effect of Actions:
Self-LoadWindSnowVariable loadsTemperatureFire....
Rd
Resistance:
StructureStructural ElementsMaterials, E-Modulus etc.cross sections, Area, Moment of Inertia
Semi-probalistic safety concept
≤
Safetyfr
eque
ncy
freq
uenc
y
Effect of actionEffect of action Load carrying Load carrying capacity Rcapacity R
95% quantile95% quantile 5% quantile5% quantile
EEkk RRkk
FF MM
EEdd RRdd
SafetySafety
15
Partial Safety Factors F ( G ,Q ) , M
Gk × G + Qk × Q kmod × Rk / M (timber: M = 1,3)
Safety factors in case of fire or other accidential situations: = 1,0
4. Sicherheitskonzepte
Safety Concept - simplified
EC 5-1-1 Design of Timber Structures
Serviceability limit statesServiceability limit states
Calculation of Calculation of
• deformations deformations
• vibrations vibrations
EC 5-1-1 Design of Timber Structures Design and calculation principles
III.1 Eurocode 5 in basic; loads/actions on structures
. the combination of actions under consideration
d Q kQ Q
d G kG G
Increase the actions/load by partial safety factors gamma factors)
less safety risks
Design situation G Q
Structural design calculation
favourable effect 1,0 -
unfavourable effect 1,35 1,5
Check at servicability limit state
1,0 1,0
EC 5-1-1 Design of Timber Structures
Design values of actionsDesign values of actionscharacteristic (rare) combination: characteristic (rare) combination: GGk,jk,j + Q + Qk,1k,1 + + 0,i 0,i QQk,ik,i
GGkk + W + Wkk + + 0,50,5 SSkk
quasi-permanent combination:quasi-permanent combination:GGk,jk,j + + 2,i 2,i QQk,ik,i
GGkk + + 0,00,0 WWkk + + 0,00,0 SSkk
Serviceability limit statesServiceability limit states
EC 5-1-1 Design of Timber Structures
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor
Safety factorSafety factor
timbertimber
Load duration - and Load duration - and service-class service-class
Safety factorSafety factor
EC 5-1-1 Design of Timber Structures
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor w+s/2 or s+w/2w+s/2 or s+w/2
Safety factorSafety factor
timbertimber
Load duration - and Load duration - and service-class service-class
Safety factorSafety factor
EC 5-1-1 Design of Timber Structures
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor w+s/2 or s+w/2w+s/2 or s+w/2
Safety factorSafety factor = 1,35 (G)= 1,35 (G) = 1,50 (Q)= 1,50 (Q)
timbertimber
Load duration - and Load duration - and service-class service-class
Safety factorSafety factor
EC 5-1-1 Design of Timber Structures
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor w+s/2 or s+w/2w+s/2 or s+w/2
Safety factorSafety factor = 1,35 (G)= 1,35 (G) = 1,50 (Q)= 1,50 (Q)
= ?= ?(permissible stress)(permissible stress)
timbertimber
Load duration - and Load duration - and service-class service-class
Safety factorSafety factor
EC 5-1-1 Design of Timber Structures
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor w+s/2 or s+w/2w+s/2 or s+w/2
Safety factorSafety factor = 1,35 (G)= 1,35 (G) = 1,50 (Q)= 1,50 (Q)
= ?= ?(permissible stress)(permissible stress)
timbertimber
Load duration - and Load duration - and service-class service-class
kkmodmod
0,6 permanent,SC 10,6 permanent,SC 10,9 short, SC 10,9 short, SC 10,5 0,5 permanent, SC 3
0,7 short, SC 30,7 short, SC 3
Safety factorSafety factor
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor w+s/2 or s+w/2w+s/2 or s+w/2
Safety factorSafety factor = 1,35 (G)= 1,35 (G) = 1,50 (Q)= 1,50 (Q)
= ?= ?(permissible stress)(permissible stress)
timbertimber
Load duration - and Load duration - and service-class service-class
kkmodmod
0,6 permanent,SC 10,6 permanent,SC 10,9 short, SC 10,9 short, SC 10,5 0,5 permanent, SC 3
0,7 short, SC 30,7 short, SC 3
??(permissible stress) (permissible stress)
Reduction of 1/6 Reduction of 1/6 (SC 3)(SC 3)
Safety factorSafety factor
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor w+s/2 or s+w/2w+s/2 or s+w/2
Safety factorSafety factor = 1,35 (G)= 1,35 (G) = 1,50 (Q)= 1,50 (Q)
= ?= ?(permissible stress)(permissible stress)
timbertimber
Load duration - and Load duration - and service-class service-class
kkmodmod
0,6 permanent,SC 10,6 permanent,SC 10,9 short, SC 10,9 short, SC 10,5 0,5 permanent, SC 3
0,7 short, SC 30,7 short, SC 3
??(permissible stress) (permissible stress)
Reduction of 1/6 Reduction of 1/6 (SC 3)(SC 3)
Safety factorSafety factor = 1,3 (5%-Quantil)= 1,3 (5%-Quantil)
Comparison of safety conceptsComparison of safety concepts
Taking into account Taking into account Semi-probalistic Semi-probalistic methodmethod
Concept of Concept of permissible permissible
stressesstresses
ActionAction
combinationscombinations Combination factor Combination factor w+s/2 or s+w/2w+s/2 or s+w/2
Safety factorSafety factor = 1,35 (G)= 1,35 (G) = 1,50 (Q)= 1,50 (Q)
= ?= ?(permissible stress)(permissible stress)
timbertimber
Load duration - and Load duration - and service-class service-class
kkmodmod
0,6 permanent,SC 10,6 permanent,SC 10,9 short, SC 10,9 short, SC 10,5 0,5 permanent, SC 3
0,7 short, SC 30,7 short, SC 3
??(permissible stress) (permissible stress)
Reduction of 1/6 Reduction of 1/6 (SC 3)(SC 3)
Safety factorSafety factor = 1,3 (5%-Quantil)= 1,3 (5%-Quantil)
= ?= ?(permissible stress)(permissible stress)
EC 5-1-1 Design of Timber Structures Design and calculation principles
kmod · fk kmod for the action/load with shortest design situation
Ultimate limit state:
Serviceability limit state:
separate for each action/load
wel · (1+ kdef)
def
E
1 k
Influence of service classes and duration of load
EC 5-1-1 Design of Timber Structures Design and calculation principles
III.1 Eurocode 5 in basic; loads/actions on structures
Ultimate limit state: 05d mod
M
XX k
Bending strength:m,k
m,d modM
ff k
t ,0 ,kt ,0,d mod
M
ff k
Servicability limit state: d mX X
Modulus of elasticity: d 0,meanE E
Design value of material properties:
Tensile strength:
EC 5-1-1 Design of Timber Structures Design and calculation principles
d fd
loading resistance
freq
uen
cy
M
Ek
design values
5%-quantiles
fk
x G
QEd
x kmod
III.1 Eurocode 5 in basic; loads/actions on structures
Structural design calculation:
EC 5-1-1 Design of Timber Structures Design and calculation principles
Strength properties for timber (Tab. F. 5 DIN 1052)
(for exact national data see: National Annexes)
EC 5-1-1 Design of Timber Structures Design and calculation principles
Strength properties for gluelam (Tab. F. 9 DIN 1052)
(for exact national data see: National Annexes)
EC 5-1-1 Design of Timber Structures Design and calculation principles
++
-
-
+
-
z
z
yy+
+
-
-
+
-
z
z
yy
Vd
Maße in cm
6
5
12
18
12
24
III.2 Bending, shear, buckling
Design resistance for cross-sections
EC 5-1-1 Design of Timber Structures Design and calculation principles
Vd = design value of the shear force S = static moment (section modulus)
= b·h2/8 (rectangle cross-section)I = second moment of area (moment of inertia)
= b·h3/12 (rectangle cross-section)b = width
fv,d = design shear strength for the actual condition
dd v,d
V1,5 f
A d
v ,d
1,5 V A1
f
dd v,d
V Sf
I b
d
v,d1
f
Shear force
EC 5-1-1 Design of Timber Structures Design and calculation principles
dd
v ,dv ,d
A in cm²V
erf A 15 with V in kNf
f in N/mm²
proportioning:
dd v ,d
V15 f
A d
v ,d
V A15 1
f
d in [N/mm²]
Vd in [kN]
A in [cm²]fv,d in [N/mm²]
dd
A in cm²erf A 9 V with
V in kN
For sawn timber C 24, service class 2 and medium term action:
EC 5-1-1 Design of Timber Structures Design and calculation principles
uniaxial bending
construction
Pfette
Sparren
static systems
dm,d m,d
n
Mf
W d n
m,d
M / W1
f
m,d = design value of bending stress
Md = design value of bending moment
Wn = netto moment of resistance considering the cross section weaks
fm,d = design value of bending strength
rafter
purlin
EC 5-1-1 Design of Timber Structures Design and calculation principles
600 mm h fm,y,k
250 mm h 600 mm
h 250 mm fm,y,k · 1,1
h
0,1
m,y ,k600
fh
dm,d m,d
n
M1000 f
W d n
m,d
M / W1000 1
f
m,d in [N/mm²]
Md in [kNm]
Wn in [cm³]
fm,d in [N/mm²]
E.g. gluelam influence of height:
Ultimate limit state
EC 5-1-1 Design of Timber Structures Design and calculation principles
nd
n dm,d
m,d
W in cm³M
erf W 1000 mit M in kNmf
f in N/mm²
proportioning:
For sawn timber C 24, service class 2 and medium term action:
nn d
d
W in cm³erf W 68 M with
M in kNm
EC 5-1-1 Design of Timber Structures Design and calculation principles
4,3
m
w
y y
100 100 mm
yy wz
qz
yy wz
Fc
Fc
Biegung um y-Achsem,y
Knicken um y-Achsekc,y
Stability of Members
EC 5-1-1 Design of Timber Structures Design and calculation principles
imperfections additional bending moment
c,0,dc,0,d c c,0,d
n
Fk f
A c,0,d n
c c,0,d
F A1
k f
An: local cross section weakenings might be neglected at the stress verification if they are not situated in the middle third of the buckling length.kc: local cross section weakenings might be neglected at the calculation of the buckling coefficient.
Compression members endangered by buckling
Structural design calculation using compressive stress values and reduced compressive strength:
EC 5-1-1 Design of Timber Structures Design and calculation principles
c2 2
rel ,c
1k 1
k k
buckling coefficient / instability factor
k = 2c rel ,c rel ,c0,5 1 0,3
c = 0,2 for solid timber 0,1 for glued laminated timber and LVL
rel,c = Relative Slendernessc,0,k c,0,kef
0,05 0,05
f f
i E E
= ef
i
= Slenderness
ef = · s = effective lenght
= buckling length coefficient
i I A
EC 5-1-1 Design of Timber Structures Design and calculation principles
buckling length coefficient
EC 5-1-1 Design of Timber Structures Design and calculation principles
compression member with intermediate lateral support:
buckling length = distance of lateral supports
different buckling lengths ef,y and ef,z :
2
1y z
Scheibe
hho
hu3
z y
h
EC 5-1-1 Design of Timber Structures Design and calculation principles
procedure at the design calculation:
1. determination of buckling lengths ef for buckling around the principal axis
2. calculation of the slenderness ratio y and z
3. determination of instability factors kc,y und kc,z
ef i with i = 0,289 · h resp. = 0,289 · w at rectangular cross sections
4. verification of buckling resistance
c,0,dc,0,d c c,0,d
n
F10 k f
A c,0,d n
c c,0,d
F A10 1
k f
c,0,d in [N/mm²]
Fc,0,d in [kN]
An in [cm²]
fc,0,d in [N/mm²]
EC 5-1-1 Design of Timber Structures Design and calculation principles
a A Nd, max in kN for a buckling length of lef in m
mm mm² 2,00 2,50 3,00 3,50 4,00 4,50 5,00 5,50 6,00 6,50 7,00
100 10000 72 50,4 36,4 27,4 21,3 17 13,9 11,5 9,7 8,3 7,2
120 14400 130 97,6 72,5 55,2 43,2 34,6 28,3 23,6 20 17,1 14,8
140 19600 202 164 127 98,7 78 62,9 51,6 43,1 36,6 31,4 27,2
160 25600 284 247 202 161 129 105 86,5 72,5 61,5 52,9 45,9
180 32400 375 340 293 243 199 163 136 114 97,1 83,6 72,7
200 40000 476 444 399 343 288 240 201 170 146 126 109
220 48400 587 557 514 459 397 337 286 244 209 181 158
240 57600 709 679 639 586 522 454 391 336 290 252 221
260 67600 841 812 773 723 660 588 515 448 390 340 299
Design resistance of squared columns C 24 in Service class 2 for medium action load
for axail compression a
a
EC 5-1-1 Design of Timber Structures Design and calculation principles
Serviceability limit state
Limiting values: Only Recommendations, disregarding is possible
EC 5-1-1 Design of Timber Structures Design and calculation principles
Vibrations:
To reduce vibrations the fundamental frequency of the floors should be greater than 8 Hz.
EC 5-1-1 Design of Timber Structures Design and calculation principles
Vibrations:
High stiffness of the floor reduce the vibration,
Little deflection under permanent load,
frequency greater than 8 Hz.
For single-span beams
In residential buildings vibrations of the floors often cause unacceptable discomfort to the users. To reduce vibrations the fundamental frequency of the floors should be greater than 8 Hz.
g*,instw 6 mm
EC 5-1-1 Design of Timber Structures Design and calculation principles
Designtables for estimate calculations given in timberdesigntables.pdf
Notice:
First ask for the national standard cross-sectional dimensions, they differ in different territories!
EC 5-1-1 Design of Timber Structures Design and calculation principles
EC 5-1-1 Design of Timber Structures Design and calculation principles
Span tables for Timber C 24 in for floor joists permanent (dead) load gk in kN/m²Single span beams for ulitmate limit state and serviceability limit state except vibration imposed load qk in kN/m²
l gk
m kN/m² 0,60 0,70 0,80 0,90 1,00 0,60 0,70 0,80 0,90 1,001,5 60 x 160 60 x 180 60 x 180 60 x 200 60 x 200 60 x 180 60 x 200 60 x 200 60 x 240 60 x 2401,75 60 x 160 60 x 180 60 x 200 60 x 200 60 x 240 60 x 180 60 x 200 60 x 200 60 x 240 60 x 240
2 60 x 180 60 x 180 60 x 200 60 x 200 60 x 240 60 x 180 60 x 200 60 x 240 60 x 240 60 x 2402,25 60 x 180 60 x 180 60 x 200 60 x 240 60 x 240 60 x 200 60 x 200 60 x 240 60 x 240 60 x 2401,5 60 x 180 60 x 180 60 x 240 60 x 240 60 x 240 60 x 200 60 x 240 60 x 240 60 x 240 80 x 2401,75 60 x 200 60 x 200 60 x 240 60 x 240 60 x 240 60 x 240 60 x 240 60 x 240 80 x 240 80 x 240
2 60 x 200 60 x 200 60 x 240 60 x 240 80 x 240 60 x 240 60 x 240 60 x 240 80 x 240 80 x 2402,25 60 x 200 60 x 240 60 x 240 60 x 240 80 x 240 60 x 240 60 x 240 80 x 240 80 x 240 80 x 2401,5 60 x 240 60 x 240 60 x 240 80 x 240 80 x 240 60 x 240 80 x 240 80 x 240 80 x 240 120 x 2401,75 60 x 240 60 x 240 80 x 240 80 x 240 80 x 240 60 x 240 80 x 240 80 x 240 120 x 200 120 x 240
2 60 x 240 60 x 240 80 x 240 80 x 240 80 x 240 60 x 240 80 x 240 80 x 240 120 x 240 120 x 2402,25 60 x 240 60 x 240 80 x 240 80 x 240 120 x 200 80 x 240 80 x 240 120 x 200 120 x 240 120 x 2401,5 60 x 240 80 x 240 80 x 240 120 x 200 120 x 240 80 x 240 80 x 240 120 x 240 120 x 240 120 x 2401,75 60 x 240 80 x 240 80 x 240 120 x 240 120 x 240 80 x 240 120 x 200 120 x 240 120 x 240 120 x 240
2 80 x 240 80 x 240 120 x 200 120 x 240 120 x 240 80 x 240 120 x 240 120 x 240 120 x 240 -2,25 80 x 240 80 x 240 120 x 240 120 x 240 120 x 240 80 x 240 120 x 240 120 x 240 120 x 240 -1,5 80 x 240 80 x 240 120 x 240 120 x 240 120 x 240 120 x 200 120 x 240 120 x 240 - -1,75 80 x 240 120 x 200 120 x 240 120 x 240 120 x 240 120 x 240 120 x 240 120 x 240 - -
2 80 x 240 120 x 240 120 x 240 120 x 240 - 120 x 240 120 x 240 - - -2,25 80 x 240 120 x 240 120 x 240 120 x 240 - 120 x 240 120 x 240 - - -1,5 100 x 200 120 x 240 120 x 240 - - 120 x 240 120 x 240 - - -1,75 120 x 240 120 x 240 120 x 240 - - 120 x 240 - - - -
2 120 x 240 120 x 240 - - - 120 x 240 - - - -2,25 120 x 240 120 x 240 - - - 120 x 240 - - - -
Joist spacing e in m
imposed load qk = 2,0 kN/m² imposed load qk = 2,75 kN/m²
3,0
3,5
4,0
Joist spacing e in m
4,5
5,0
5,5
Span tables with german sizes, Vibrations of residential floors disregarded
EC 5-1-1 Design of Timber Structures Design and calculation principles
Span tables for Timber C 24 in for floor joistsSingle span beams for ulitmate limit state and serviceability limit state simplified vibration analysis for residential floors included
l gk
m kN/m² 0,60 0,70 0,80 0,90 1,00 0,60 0,70 0,80 0,90 1,001,5 60 x 160 60 x 180 60 x 180 60 x 200 60 x 200 60 x 180 60 x 200 60 x 200 60 x 240 60 x 2401,75 60 x 180 60 x 180 60 x 200 60 x 200 60 x 240 60 x 180 60 x 200 60 x 200 60 x 240 60 x 240
2 60 x 180 60 x 180 60 x 200 60 x 200 60 x 240 60 x 180 60 x 200 60 x 240 60 x 240 60 x 2402,25 60 x 180 60 x 200 60 x 200 60 x 240 60 x 240 60 x 200 60 x 200 60 x 240 60 x 240 60 x 2401,5 60 x 200 60 x 240 60 x 240 60 x 240 60 x 240 60 x 240 60 x 240 60 x 240 60 x 240 80 x 2401,75 60 x 240 60 x 240 60 x 240 60 x 240 80 x 240 60 x 240 60 x 240 60 x 240 80 x 240 80 x 240
2 60 x 240 60 x 240 60 x 240 80 x 240 80 x 240 60 x 240 60 x 240 60 x 240 80 x 240 80 x 2402,25 60 x 240 60 x 240 60 x 240 80 x 240 80 x 240 60 x 240 60 x 240 80 x 240 80 x 240 80 x 2401,5 60 x 240 80 x 240 80 x 240 120 x 240 120 x 240 80 x 240 80 x 240 120 x 240 120 x 240 120 x 2401,75 80 x 240 80 x 240 120 x 240 120 x 240 120 x 240 80 x 240 80 x 240 120 x 240 120 x 240 120 x 240
2 80 x 240 80 x 240 120 x 240 120 x 240 120 x 240 80 x 240 120 x 240 120 x 240 120 x 240 -2,25 80 x 240 120 x 240 120 x 240 120 x 240 - 120 x 240 120 x 240 120 x 240 - -1,5 120 x 240 120 x 240 120 x 240 - - 120 x 240 120 x 240 - - -1,75 120 x 240 120 x 240 - - - 120 x 240 - - - -
2 120 x 240 - - - - 120 x 240 - - - -2,25 120 x 240 - - - - - - - - -
4,5
Joist spacing e in m
3,0
3,5
4,0
imposed load qk = 2,0 kN/m² imposed load qk = 2,75 kN/m²
Joist spacing e in m
Span tables with german sizes, with vibrations as design requirement
EC 5-1-1 Design of Timber Structures
Thank you very much Thank you very much for your attention!for your attention!