This document summarizes key aspects of structural design basis and load considerations according to EN1990:2002 and EN1991:2002, including: 1) Ultimate limit states that must be verified including loss of equilibrium, failure or excessive deformation of members, and ground failure. Design working life ranges from 10-100 years depending on structure type. 2) Combination factors for actions affecting ultimate limit state design considering persistent/transient design situations. 3) Serviceability limit state considerations for vertical and horizontal deflections. 4) Imposed load values that vary based on building use and category from 1.5-7.5 kN/m2. Snow load is calculated based on roof angle, thermal

1. BASIS OF STRUCTURAL DESIGN
(EN1990:2002)
Ultimate limit state verification
(EN1990,cl.6.4.1(1)P)
The following ultimate limit states shall be verified as relevant:
EQU: Loss of equilibrium of the structure, (considering for sliding, overturning or uplift)
STR: Internal failure or excessive deformation of the structure of structural member (Design of structural for
strength of members and frames),
GEO: Failure due to excessive deformation of the ground (Design of structural members such as footing,
piles, basement walls, etc.),
FAT: Fatigue failure of the structure or structural member.
Design working life
(CYS NA EN1990,Table 2.1)
Design working life
category
Indicative design
working life (years)
Examples
1 10 Temporary structures (1)
2 10 – 25 Replaceable structural parts, e.g. gantry girders,
bearings
3 15 – 30 Agricultural and similar structures
4 50 Building structures and other common structures
5 100 Monumental building structures, bridges, and other
civil engineering structures
(1) Structures or parts of structures that can be dismantled with a view to being re-used should
not be considered as temporary.
In the case of replaceable structural parts the design life for the structural determination of loads should be
the design life of the structure.
Design Working life
Ultimate Limit State (ULS)
Ultimate Limit State Concern
(EN1990,cl.3.3(1)P)
 Safety of people,
 Safety of the structure
 Protection of the contents
Design situations
(EN1990,cl.3.2(2)P)
Persistent design situation: Normal use condition
Transient design situation: Temporary condition, e.g. during execution or repair
Accidental design situation: Exceptional condition, e.g. fire, explosion, impact.
Seismic design situation: Structure subject to seismic events.

2. Ultimate Limit State (ULS)
COMBINATION OF ACTIONS FOR PERSISTENT/TRANSIENT DESIGN SITUATION
(EN1990,cl.6.4.3.2)
Persistent and transient design situation – EQU Equation 6.10 (Set A)
6.10 Ed=ΣγG Gk +γQ Qk1 + γQ ψ0,2 Qk2
Action
Favourable
γ
Unfavourable
γ
Permanent (dead,
earth), γG
0.9 1.1
Variable (imposed,
wind), γQ
0 1.5
Note: Single source is not applicable for EQU design situation. Different γ factors can be used in favourable and unfavourable
areas.
Persistent and transient design situation – STR/GEO Equation 6.10, 6.10a & 6.10b (Set B)
6.10
6.10a
6.10b
Ed=ΣγG Gk +γQ Qk1 + γQ ψ0,2 Qk2
Ed=ΣξγG Gk +γQ ψ0,1 Qk1 + γQ ψ0,2 Qk2
Ed=ΣγG Gk +γQ Qk1 + γQ ψ0,2 Qk2
Action
Favourable
γ
Unfavourable
γ
Permanent (dead,
earth), γG
1.0 1.35
Variable (imposed,
wind), γQ
0 1.5
Note: Single source is applicable for STR/GEO design situation.
Persistent and transient design situation – GEO Equation 6.10 (Set C)
6.10 Ed=ΣγG Gk +γQ Qk1 + γQ ψ0,2 Qk2
Action
Favourable
γ
Unfavourable
γ
Permanent (dead,
earth), γG
1.0 1.0
Variable (imposed,
wind), γQ
0 1.3
Note: Single source is applicable for STR/GEO design situation.
Important notes
(EN1990,cl.3.2(2)P)
 Approach 2 (CYS NA EN1990,Table.A1.2(B)) should be used for the
design of the structural members of substructure (i.e. footings, piles,
basement walls, etc.) (CYS NA EN1990,cl. 2.2.3.4).
 Actions that cannot exist simultaneously due to physical of functional
reasons should not be considered together in combination.
 The use of expression 6.10a and 6.10b lead to a more economic
design in most circumstances.


3. Summary table of partial, combination and reduction factors for the STR and GEO ultimate limit states for
buildings
Expression
Unfavourable Permanent action Unfavourable Variable actions
Self-weight Imposed floor loads Wind loads Snow loads
6.10
γG=1.35 γQ,1 =1.5 γQ,iψ0,i =1.5x05=0.75 γQ,iψ0,i =1.5x05=0.75
γG=1.35 γQ,iψ0,i =1.5x07=1.05 γQ,1 =1.5 γQ,iψ0,i =1.5x05=0.75
γG=1.35 γQ,iψ0,i =1.5x07=1.05 γQ,iψ0,i =1.5x05=0.75 γQ,i =1.5
Less favourable equations 6.10a & 6.10b
6.10a
γG=1.35 γQ,iψ0,i =1.5x07=1.05 γQ,iψ0,i =1.5x05=0.75 γQ,iψ0,i =1.5x05=0.75
γG=1.35 γQ,iψ0,i =1.5x07=1.05 γQ,iψ0,i =1.5x05=0.75 γQ,iψ0,i =1.5x05=0.75
γG=1.35 γQ,iψ0,i =1.5x07=1.05 γQ,iψ0,i =1.5x05=0.75 γQ,iψ0,i =1.5x05=0.75
6.10b
ξγG=0.85*1.35 γQ,1 =1.5 γQ,iψ0,i =1.5x05=0.75 γQ,iψ0,i =1.5x05=0.75
ξγG=0.85*1.35 γQ,iψ0,i =1.5x07=1.05 γQ,1 =1.5 γQ,iψ0,i =1.5x05=0.75
ξγG=0.85*1.35 γQ,iψ0,i =1.5x07=1.05 γQ,iψ0,i =1.5x05=0.75 γQ,i =1.5
Note: Shaded boxes indicate the ‘leading variable action’,
Combination (sensitivity) factor, ψ
(CYS NA EN1990:2002, Table A1.1)
Category Specific Use
ψο ψ1 ψ2
A Domestic and residential 0.7 0.5 0.3
B Office 0.7 0.5 0.3
C Areas for Congregation 0.7 0.7 0.6
D Shopping 0.7 0.7 0.6
E Storage 1.0 0.9 0.8
F Traffic < 30 kN vehicle 0.7 0.7 0.6
G Traffic < 160 kN vehicle 0.7 0.5 0.3
H Roofs 0.7 0 0
Snow, altitude < 1000 m 0.5 0.2 0
Wind 0.5 0.2 0

4. Serviceability Limit State (SLS)
COMBINATION OF ACTIONS FOR SERVICEABILITY LIMIT STATE
(EN1990,cl.6.5.3)
Characteristic combination
Equation 6.14b
Ed=Gk +Qk,1 + ψ0 Qk,2
Frequent combination
Equation 6.15b
Ed=Gk + ψ1Qk,1 + ψ2 Qk,2
Quasi-permanent combination
Equation 6.16b
Ed=Gk + ψ2Qk,1
Characteristic value of variable actions
For each variable action there are four representative values:
1.The characteristic value Qk (determine by insufficient data).
2.The combination value ψ0Qk (of an action is intended to take account of the
reduced probability of the simultaneous of two or more variable actions).
3. Frequent value ψ1Qk (exceeded only for a short period of time and is used
primary for the SLS and also the accidental ULS).
4. Quasi-permanent value ψ2Qk (exceeded for a considerable period of time or
considered as an average loading over time and used for the long-term affects
at the SLS and also accidental and seismic ULS).
INDICATIVE LIMITING VALUES FOR VERTICAL DEFLECTIONS
(Manual of EC0 &EC1, Table D.1)
Serviceability Limit States
Vertical deflections
Serviceability Requirement Characteristic Combination (Expression 6.14b
in EC0) wmax
Function and damage to non-
structural elements (e.g.
partition walls claddings etc)
–Brittle
-Non-brittle
Function and damage to
structural elements
≤L/500 to L/360
≤L/300 to L/200
≤L/300 to L/200
Serviceability Limit State (SLS) – Vertical and Horizontal deformations

5. INDICATIVE LIMITING VALUES FOR HORIZONTAL DEFLECTIONS
(Manual of EC0 &EC1, Table D.2)
Serviceability Limit States
Vertical deflections
Serviceability Requirement Characteristic Combination (Expression 6.14b
in EC0) wmax
Function and damage to non-
structural elements
–Single storey buildings top
of column
-Each storey in a multi-storey
building
-The structure as a whole for
a multi-storey building
u≤H/300
u≤H/500 to H/300
u≤H/500

6. Category of use
(EN1991-1-1:2002,Table 6.1)
Category Specific Use Example
A Area for domestic and
residential activities
Rooms in residential buildings and houses bedrooms and wards in
hospitals, bedrooms in hotels and hostels kitchens and toilets
B Office areas
C Areas where people may
congregate (with the
exception of areas
defined under category
A, B, and D1))
C1: Areas with tables, etc. e.g. areas in schools, cafés, restaurants,
dining
halls, reading rooms, receptions.
C2: Areas with fixed seats, e.g. areas in churches, theatres or
cinemas, conference rooms, lecture halls, assembly halls, waiting
rooms, railway waiting rooms.
C3: Areas without obstacles for moving
people, e.g. areas in museums, exhibition rooms, etc. and access
areas in public and administration buildings, hotels, hospitals,
railway station forecourts.
C4: Areas with possible physical activities, e.g. dance halls,
gymnastic rooms, stages.
C5: Areas susceptible to large crowds, e.g. in buildings for public
events like concert halls, sports halls including stands, terraces and
access areas and railway platforms.
D Shopping areas D1: Areas in general retail shops
D2:Areas in departments stores
Imposed loads
(EN 1991-1-1:2002, Table 6.2)
Category Of loaded areas qk
(kN/m2
)
Qk
(kN)
Category A
-Floors
-Stairs
-Balconies
Category B
Category C
-C1
-C2
-C3
-C4
-C5
Category D
-D1
-D2
1.5-2.0
2.0-4.0
2.5-4.0
2.0-3.0
2.0-3.0
3.0-4.0
3.0-5.0
4.5-5.0
5.0-7.5
4.0-5.0
4.0-5.0
2.0-3.0
2.0-4.0
2.0-3.0
1.5-4.5
3.0-4.0
2.5-7.0
4.0-7.0
3.5-7.0
3.5-4.5
3.5-7.0
3.5-7.0Imposed load on Roof
(CYS NA EN1991-1-1, Table 6.10)
Sub-category Actions
Imposed load,
qk
(kN/m2
)
Q (kN)
H
Roof (inaccessible except for
normal maintenance and repair)
0.4 1.0
STRUCTURAL LOADS
(EN1991:2002)
Imposed Loads

7. Permanent load
(EN 1991-1-1:2002, Table A.1-A.12)
Materials Density, γ
(kN/m3
)
Modulus of
Elasticity, E
kN/mm2
Reinforced Concrete
Steel
Glass
Water
Plastic PTFE
Softwood timber
Hardwood timber
Concrete blockwork
Asphalt
Roof tiles
Soil (Sand)
Soil (Clay)
Insulation board
Aluminium
Copper
Cement mortar
Νylon
Epoxy resin
Polystyrene
Carbon fibre
Fibre glass
Granite
25
78
25
10
21-22
5
7
18
22
20
16-18
20-22
3
27
87-89
19-23
11.5
16-20
10-13
20
15
26
17-31
210
74
-
0.3-0.6
10
12
-
-
5-30
-
-
-
69
96
20-31
2-3.5
20
3-3.3
415
10
40-70
Permanent Loads
Typical unit floor Typical loadings Typical unit floor Typical loadings
Steel floor kN/m2
Self weight of beam 0.25
Self weight of decking 0.10
Self weight of meshing 0.05
Ceiling and services 0.15
Total 0.55
Internal ConcreteFloor kN/m2
Partition (minimum) 1.00
Screed (5-70cm) 1.20-1.80
Raised floor 0.40
Concrete floor (15cm) 3.75
Celling and services 0.15
Total 6.50-7.10
External Concrete Floor kN/m2
Slabs / paving 0.95
Screed (50cm) 1.20
Asphalt waterproofing 0.45
Concrete floor (15cm) 3.75
Celling and services 0.15
Total 6.50
Metal deck roofing kN/m2
Live loading: snow/
wind uplift 0.6-1.0
Outer covering, insulation and
metal deck liner 0.30
Purlins-150 deep at 1.5m c/c 0.10
Services 0.10
Total 1.1-1.5
Timber Floor kN/m2
Partition 1.00
Timber boards/plywood 0.15
Timber joist 0.20
Celling and services 0.15
Total 1.50
Timber Flat Roof kN/m2
Asphalt waterproofing 0.45
Timber joist and insulation 0.20
Celling and services 0.15
Total 0.80

8. SNOW LOAD
(EN1991-1-3)
Snow load on roof for transient design situations
s=μiCeCtsk
(EN 1991-1-3Equ.5.1)
Snow load shape coefficients, μ
(EN1991-1-3, Table 5.2)
Angle of pitch of
roof, a
0ο
≤α≤30ο
30ο
≤α≤60ο
α≥60ο
μ1 0.8 0.8(60-α)/30 0
μ2 0.8+0.8 α/30 1.6 -
For monopitch roof use only μ1
For pitched roof use μ1andμ2
THERMAL COEFFICIENTS C
(ΕΝ1991-1-3¨2003, cl. 5.2(8))
Ct=1.0
Thermal transmission on the roof
<1W/m2
K
Exposure coefficient(ΕΝ1991-1-3, Table 5.1)
Topography Ce
Windswept 0.8
Normal 1.0
Sheltered 1.2
CHARACTERISTIC SNOW LOAD
ON GROUND,sk (kN/m2
)
(CYS NA ΕΝ1991-1-3, cl. NA 2.7)
sk = 0.289*(1+(A/452)2
)
A:is the attitude above sea level (m)
Snow load shape coefficients for cylinder roofs, μ
(EN1991-1-3, Eq. 5.4-5.5)
μ1 0.8 μs=0 a≤15o
μ2 μs+μw
μw=(b1+b2)/2h ≤ γh/sk Range must:0.8≤μw≤4
γ:is the weight density of snow may taken as 2kN/m3
Angle of pitch of roof, a β>60ο
β≤60
μ3 should be less than μ3≤2 0 0.2+10 h/b
Monopitch roof Pitch roof Cylinder roof

9. WIND LOAD
(EN1991-1-4)
Fundamental Basic wind velocity, vb,0
(CYS NA EN1991-1-4,Fig.1)
Directional factor
(CYSEN1991-1-4,NA 2.4)
cdir=1.0
(Conservative value for all direction)
Season factor
(CYS EN1991-1-4,NA 2.4)
cseason=1.0
Basic wind velocity
(EN1991-1-4, Eq. 4.1)
vb=cdir.cseasonvb,0
BASIC WIND VELOCITY

10. STRUCTURAL FACTOR
(EN1991-1-4, cl.6.0)
cscd =1.0
Builiding with less than
h≤15m
Natural frequency
f≤5Hz
Walls≤100m high Chimney with circular
cross-sectional area and,
h≤60m
h≤6.5·diameter
h
Determination of cscd
Determine of structural factor cscd
Size factor
(EN1991-1-4,Eq.6.2)
It is on the safe side to use
B2
=1 kp=3
Calculation of R2
can be found in Annex B of
EN1991-1-4:2005
Can be found
Dynamic factor
(EN1991-1-4,Eq.6.3)
It is on the safe side to use
B2
=1 kp=3
Calculation of R2
can be found in Annex B of
EN1991-1-4:2005
Consider Ignore
Upwind Slope≤3o
NOYES
TERRAIN OROGRAPHY,
(EN1991-1-4, cl.4.3.3)
Detail calculation of terrain orography
factor can be found in Annex A of
EN1991-1-4:2005

11. PEAK VELOCITY PRESSURE
Roughness factor, cr(z)
(EN1991-1-4,Eq.4.3-4.5)
cr(z)=kr . ln(z/z0) for zmin≤z≤zmax
cr(z)=cr . (zmin) for z≤zmin
z0: is the roughness length
Maximum height, zmax
(EN1991-1-4, cl. 4.3.2)
zmax=200m
Orography factor co(z)
co(z)=1
Terrain factor,
(EN1991-1-4,cl.4.4)
kr=0.19(z0/z0,II)0.07
Mean wind velocity, vm(z)
(EN1991-1-4 cl.4.3.1 )
vm(z)=cr(z).co(z).vb
Wind turbulence, Iv(z)
(EN1991-1-4,Eq.4.7)
Iv(z)=σv/vm(z)=kl/co(z)ln(z/z0) for
zmin≤z≤zmax
Iv(z)=Iv(zmin) for z≤zmin
Turbulence factor: kl=1.0
(NA CYS EN1991-1-4, cl. NA 2.10)
Note: for co(z)=1 Iv(z) is not important
Peak velocity pressure, qpeak(z)
(EN1991-1-4 Eq.4.8 )
qpeak(z)=[1+7 Iv(z)]0.5ρ vm
2
(z)=ce(z)·0.5·ρ·vb
2
Air density:ρ=1.25kg/m3
Terrain category and terrain parameters (EN1991-1-4, Tab.:4.1)
Terrain
category
Description z0 (m) zmin(m)
0
Sea, costal area exposed to the open
sea.
SEA 0.003 1
I
Lakes or area with negligible
vegetation and without obstacles.
COUNTRY
0.01 1
II
Area with low vegetation such as
grass and isolated obstacles trees,
buildings) with separations of at least
20 obstacle height.
0.05 2
III
Area with regular cover of vegetation
or buildings or woth isolatd obstacles
with seperations of maximum 20
obstacle height (such as villages,
suburban terrain, permanent forest). TOWN
0.3 5
IV*
Area in which at least 15% of the
surface is covered with building and
their average height exceeds 15m.
1.0 10
*
For buildings in terrain category IV, displacement height hdis should be consider and information can be found in Aneex A.5 of EN1991-1-4:2005

12. Values of external pressure coefficient for vertical walls of rectangular plan buildings
(EN1991-1-4, Tab.:4.1)
ZONE A B C D E
h/d cpe,10 cpe,1 cpe,10 cpe,1 cpe,10 cpe,1 cpe,10 cpe,1 cpe,10 cpe,1
5 -1.2 -1.4 -0.8 -1.1 -0.5 +0.8 +1.0 -0.7
1 -1.2 -1.4 -0.8 -1.1 -0.5 +0.8 +1.0 -0.5
≤0.25 -1.2 -1.4 -0.8 -1.1 -0.5 +0.7 +1.0 -0.3
Note: Values for cpe,1 are intended for the design of small elements and fixings with an element of 1m2
or
less such as cladding elements and roofing elements. Values for cpe,10 may be used for the design of the
overall load bearing structure of buildings. The external pressure coeffiecient cpe,1 and cpe,10 is using for
loadaded area of 1m2
and 10m2
respectively.
Reference height ze, depending on h and b, and corresponding velocity pressure profile
(EN1991-1-4, Fig. 7.4)
Key for vertical walls – Flat Roof
(EN1991-1-4, Fig.7.5)
Key for vertical walls –Mono&dual pitch
Roof
(EN1991-1-4, Fig.7.5)
Pressure on surface &Wind force (EN1991-1-4, Eq. 5.1&5.5)
we=qp(ze).(cpe +cpi) & Fw=cscd·Σwe·Aref
EXTERNAL WIND PRESSURE/FORCE ON WALLS

13. EXTERNAL WIND PRESSURE/FORCE ON FLAT ROOF
Recommended values of external pressure coefficients for flat roofs
(EN1991-1-4,Tab. 7.2)
Roof type
Zone
F G H I
cpe,10 cpe,1 cpe,10 cpe,1 cpe,10 cpe,1 cpe,10 cpe,1
Sharp eaves -1.8 -2.5 -1.2 -2.0 -.07 -1.2 +0.2
With
Parapets
hp/h=0.025 -1.6 -2.2 -1.1 -1.8 -0.7 -1.2 -0.2
hp/h=0.05 -1.4 -2.0 -0.9 -1.6 -0.7 -1.2 +0.2
hp/h=0.10 -1.2 -1.8 -0.8 -1.4 -0.7 -1.2 -0.2
Curved
Eaves
r/h=0.05 -1.0 -1.5 -1.2 -1.8 -0.4 +0.2
r/h=0.10 -0.7 -1.2 -0.8 -1.4 -0.3 -0.2
r/h=0.20 -0.5 -0.8 -0.5 -0.8 -0.3 +0.2
Mansard
Eaves
a=30o
-1.0 -1.5 -1.0 -1.5 -0.3 -0.2
a=45o
-1.2 -1.8 -1.3 -1.9 -0.4 +0.2
a=60o
-1.3 -1.9 -1.3 -1.9 -0.5 -0.2
Note: Values for cpe,1 are intended for the design of small elements and fixings with an element of 1m2
or
less such as cladding elements and roofing elements. Values for cpe,10 may be used for the design of the
overall load bearing structure of buildings. The external pressure coeffiecient cpe,1 and cpe,10 is using for
loadaded area of 1m2
and 10m2
respectively.
Pressure on surface &Wind force (EN1991-1-4, Eq. 5.1&5.5)
we=qp(ze).(cpe +cpi) & Fw=cscd·Σwe·Aref

14. Recommended values of external pressure coefficients for monopitch roofs
(EN1991-1-4,Tab. 7.3a)
Pitch
Angle
a
Zone for wind direction θ=0o
Zone for wind direction θ=180o
F G H F G H
cpe,10 cpe,1 cpe,10 cpe,10 cpe,1 cpe,10 cpe,10 cpe,1 cpe,10 cpe,1 cpe,10 cpe,1
5o
-1.7 -2.5 -1.2 -2.0 -0.6 -1.2 -2.3
-2.5 -1.3 -2.0 -0.8 -1.2
+0.0 +0.0 +0.0
15o
-0.9 -2.0 -0.8 -1.5 -0.3
-2.5 -2.8 -1.3 -2.0 -0/9 -1.2
+0.2 +0.2 +0.2
30o
-0.5 -1.5 -0.5 -1.5 -0.2
-1.1 -2.3 -0.8 -1.5 -0.8
+0.7 +0.7 +0.4
45o
-0.0 -0.0 -0.0
-0.6 -1.3 -0.5 -0.7
+0.7 +0.7 +0.6
60o
+0.7 +0.7 +0.7 -0.5 -1.0 -0.5 -0.5
75o
+0.8 +0.8 +0.8 -0.5 -1.0 -0.5 -0.5
Recommended values of external pressure coefficients for monopitch roofs
(EN1991-1-4,Tab. 7.3b)
Pitch
Angle
a
Zone for wind direction θ=90o
Fup Flow G H I
cpe,10 cpe,1 cpe,10 cpe,10 cpe,1 cpe,10 cpe,10 cpe,1 cpe,10 cpe,1
5o
-2.1 -2.6 -2.1 -2.4 -1.8 -2.0 -0.6 -1.2 -0.5
15o
-2.4 -2.9 -1.6 -2.4 -1.9 -2.5 -0.8 -1.2 -0.7 -1.2
30o
-2.1 -2.9 -1.3 -2.0 -1.5 -2.0 -1.0 -1.3 -0.8 -1.2
45o
-1.5 -2.4 -1.3 -2.0 -1.4 -2.0 -1.0 -1.3 -0.9 -1.2
60o
-1.2 -2.0 -1.2 -2.0 -1.2 -2.0 -1.0 -1.3 -0.7 -1.2
75o
-1.2 -2.0 -1.2 -2.0 -1.2 -2.0 -1.0 -1.3 -0.5
Note: Values for cpe,1 are intended for the design of small elements and fixings with an element of 1m2
or less such
as cladding elements and roofing elements. Values for cpe,10 may be used for the design of the overall load bearing
structure of buildings. The external pressure coeffiecient cpe,1 and cpe,10 is using for loadaded area of 1m2
and 10m2
respectively.
EXTERNAL WIND PRESSURE/FORCE ON MONOPITCH ROOF
Pressure on surface &Wind force (EN1991-1-4, Eq. 5.1&5.5)
we=qp(ze).(cpe +cpi) & Fw=cscd·Σwe·Aref

15. Recommended values of external pressure coefficients for duopitch roofs
(EN1991-1-4,Tab. 7.4a)
Pitch
Angle
a
Zone for wind direction θ=0o
F G H I J
cpe,10 cpe,1 cpe,10 cpe,10 cpe,1 cpe,10 cpe,10 cpe,1 cpe,10 cpe,1
-45o
-0.6 -0.6 -0.8 -0.7 -1.0 -1.5
-30o
-1.1 -2.0 -0.8 -1.5 -0.8 -0.6 -0.8 -1.4
-15 o
-2.5 -2.8 -1.3 -2.0 -0.8 -1.2 -0.5 -0.7 -1.2
-5 o
-2.3 -2.5 -1.2 -2.0 -0.8 -1.2
+0.2 +0.2
-0.6 -0.6
5 o -1.7 -2.5 -1.2 -2.0 -0.6 -1.2
-0.6
+0.2
+0.0 +0.0 +0.0 -0.6
15 o -0.9 -2.0 -0.8 -1.5 -0.3 -0.4 -1.0 -1.5
+0.2 +0.2 +0.2 +0.0 +0.0 +0.0
30 o -0.5 -1.5 -0.5 -1.5 -0.2 -0.4 -0.5
+0.7 +0.7 +0.4 +0.0 +0.0
45 o -0.0 -0.0 -0.0 -0.2 -0.3
+0.7 +0.7 +0.6 +0.0 +0.0
60 o
+0.7 +0.7 +0.7 -0.2 -0.3
75 o
+0.8 +0.8 +0.8 -0.2 -0.3
Recommended values of external pressure coefficients for duopitch roofs
(EN1991-1-4,Tab. 7.4b)
Pitch
Angle a
Zone for wind direction θ=90o
F G H I
cpe,10 cpe,1 cpe,10 cpe,10 cpe,1 cpe,10 cpe,10 cpe,1
-45o
-1.4 -2.0 -1.2 -2.0 -1.0 -1.3 -0.9 -1.2
-30o
-1.5 -2.1 -1.2 -2.0 -1.0 -1.3 -0.9 -1.2
-15o
-1.9 -2.5 -1.2 -2.0 -0.8 -1.2 -0.8 -1.2
-5o
-1.8 -2.5 -1.2 -2.0 -0.7 -1.2 -0.6 -1.2
5o
-1.6 -2.2 -1.2 -2.0 -0.7 -1.2 -0.6
15o
-1.3 -2.0 -1.2 -2.0 -0.6 -1.2 -0.5
30o
-1.1 -1.5 -1.4 -2.0 -0.8 -1.2 -0.5
45o
-1.1 -1.5 -1.4 -2.0 -0.9 -1.2 -0.5
60o
-1.1 -1.5 -1.4 -2.0 -0.8 -1.2 -0.5
75o
-1.1 -1.5 -1.4 -2.0 -0.8 -1.2 -0.5
EXTERNAL WIND PRESSURE/FORCE ON DUOPITCH ROOF
Pressure on surface &Wind force (EN1991-1-4, Eq. 5.1&5.5)
we=qp(ze).(cpe +cpi) & Fw=cscd·Σwe·Aref