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III. LOAD EVALUATION

Load classification:

a)Permanent loads

-own weight of the structure (slabs, girders,

columns, roof, walls);

-earth pressure

b)Variable loads

-live loads;

-snow;

-wind

c)Exceptional loads

-earthquake.

a) Permanent loads

The permanent loads are the result of the own weight of

the structural elements, of the non-structural elements of the

building and of other loads having a permanent action: earth

pressure.

The own weight of the elements are computed by

multiplying the volume of the element with the specific weight of

the material they are made of.

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1.Superior floor slab

No. LayerThickness

[m]

Specific

weight

[daN/m3]

n

Load value

[daN/m2]

characteristic design

1 Plaster 0.01 1900 1.35 19 25.65

2 RC slab 0.10 2500 1.35 250 337.5

3 Blinding concrete 0.02 2100 1.35 42 56.7

4 Thermoinsulation 0.12 130 1.35 15.6 21.06

5 Protection layer 0.03 2100 1.35 63 85.05

Total 389.6 524.96

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2. Current foor slab

i) warm foor

No. LayerThickness

[m]

Specific

weight

[daN/m3]

n

Load value

[daN/m2]

characteristic design

1 Parquet 0.01 73 1.35 0.73 0.99

2 Leveling concrete 0.04 2100 1.35 84 113.4

3 RC slab 0.10 2500 1.35 250 337.54 Plaster 0.01 1900 1.35 19 25.65

Total 353.73 477.54

ii) cold floor

No. LayerThickness

[m]

Specific

weight

[daN/m3]

n

Load value

[daN/m2]

characteristic design

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1 Tile 0.01 1900 1.35 19 25.65

2 Leveling concrete 0.04 2100 1.35 84 113.4

3 RC slab 0.10 2500 1.35 250 337.5

4 Plaster 0.01 1900 1.35 19 25.65

Total 372 502.2

iii) circulated terrace

No. LayerThickness

[m]

Specific

weight

[daN/m3]

n

Load value

[daN/m2]

characteristic design

1 Plaster 0.01 1900 1.35 19 25.652 RC slab 0.10 2500 1.35 250 337.5

3 Leveling concrete 0.03 2100 1.35 63 85.05

4 Thermoinsulation 0.12 200 1.35 24 32.4

5 Sand 0.03 1600 1.35 48 64.8

6 Mosaic plates 0.03 2000 1.35 60 81

Total 464 626.4

iv) non-circulated terrace

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No. LayerThickness

[m]

Specific

weight

[daN/m3]

n

Load value

[daN/m2]

characteristic design1 Plaster 0.01 1900 1.35 19 25.65

2 RC slab 0.10 2500 1.35 250 337.5

3 Leveling concrete 0.03 2100 1.35 63 85.05

4 Thermoinsulation 0.12 200 1.35 24 32.4

5 Clay slate 0.06 2800 1.35 168 226.8

Total 524 707.4

3.Stairs

No. Layer Thickness

[m]

Specific

weight

n Load value

[daN/m2]

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[daN/m3] characteristic design

1 Tile 0.01 1900 1.35 19 25.65

2 RC steps 0.07 2400 1.35 168 226.8

3 RC ramp 0.10 2500 1.35 250 337.5

4 Plaster 0.015 1900 1.35 28.5 38.48Total 465.5 628.43

4.Exterior walls

No. LayerThickness

[m]

Specific

weight

[daN/m3]

n

Load value

[daN/m2]

characteristic design

1 Plaster 0.015 1900 1.35 28.5 38.48

2Light Weight

Concrete0.25 600 1.35 150 202.5

3 Thermoinsulation 0.1 200 1.35 20 27

4 Plaster 0.015 1900 1.35 28.5 38.48

Total 227 306.46

5.Dividing walls

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No. LayerThickness

[m]

Specific

weight

[daN/m3]

n

Load value

[daN/m2]

characteristic design

1 Plaster 0.015 1900 1.35 28.5 38.48

2 Brick masonry 0.10 1800 1.35 180 243

3 Plaster 0.015 1900 1.35 28.5 38.48

Total 237 319.96

Surface loads transformation into linear distributed loads:

Structural elementLoad on

m2

H

[m]

Load on

m

Exterior walls 306.46 2.85 873.42

Dividing walls 319.96 2.85 911.89

b) Variable loads

1.Live loads

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Element n

Load value

[daN/m2]

characteristic design

Superior slab 1.5 75 112.5

Current floor 1.5 300 450

Circulated terrace 1.5 400 600

Stairs 1.5 400 600

2.Snow load

= k i e t 0,ks c c s = =0.811200 160daN/m2; n=1.5;

sd= kns 1.5160 240 = = daN/m2

i- shape coefficient;i= 0.8;

ce- exposure coefficient due to the site of the construction; ce=1;

ct- thermal coefficient; ct=1;

s0,k characteristic value of snow load on the soil; s0,k= 200

daN/m2;

sk- characteristic value of snow load;

sd- design value of snow load.

c) Exceptional loads

i) Seismic action evaluation according to P100 2006:

In the modal computation, the seismic action si evaluated using

the response spectra corresponding to horizontal unidirectional ground

movements, described by accelerograms. The seismic action is described

using two horizontal components evaluated starting from the same

design response spectrum.

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When a spatial model is used, the seismic action is applied on all

relevant horizontal directions, and on the central principal directions.

For the buildings with structural elements on two normal directions,

these directions are considered relevant.

In the computation, only the vibration modes with a significant

contribution to the total seismic response will be conisdered. This

condition is fulfilled if:

the sum of the effective modal masses for the considered

modes of vibration is at least 90% from the total mass of the

structure;

all modes of vibration with an effective modal mass greater

than 5% of the total mass have been considered.

The shear force applied at the base of the building on the direction

of the seismic action:

b i dF S(T)m=

where:

i= 1.00 the building is clasified as an importance class III;

Sd(T) the ordinate of the design response spectrum corresponding

to the fundamental period T;

T the fundamental period of vibration in the plane of the

horizontal direction considered;

m the total mass of the building;

= 0.85 the correction factor which takes into account the

contribution of the fundamental mode of vibration through the effective

modal mass associated;

( )d g

TS(T) a

q

=

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ag= 0.28g the ground acceleration;

Tc= 1.00 s the corner period;

u

1

5q

=

the behaviour factor of the structure (H ductility class);

u

1

1.35;

=

(T) elastic normalised response spectrum for Tc=1.0 s

The mass on each level is computed using the software Robot

Millenium.

ii) Combination of the modal responses

The modal responses for two consecutive vibration modes, k and

k+1 are considered independent if their periods of vibration Tkand Tk+1

(where Tk+1Tk) satisfy the condition: Tk+10.9Tk.

For the maximum independent modal responses, the total

maximum effect is obtained using the modal composition relation:

2

E E,kE E=

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where:

EE the effect of seismic action (internal force, displacement);

EE,k the effect of the seismic action in mode k.

If the modal responses are not independent, other means of

combining the effects of seismic action for each mode of vibration will be

considered. (complete quadratic composition etc.).

iii) The spatial modal computation

In the case of buildings with a non-uniform distribution structural

elements masses and stiffness, the design will be made using a spatial

model of the structure. The seismic movement described in the design

response spectrum must be considered along at least two directions. The

main action directions are defined by the direction of the resultant of the

base seismic force from the first mode of vibration and the normal to this

direction. The response of the structure may be obtained by composing

the responses along these two directions.

iv) Hypothesis for design of structures with floors undeformable in

their own plane

The influence of the vertical component of the seismic

movement is neglected;

The seismic action is represented by the ground movement

along one of the principal directions x or y or along any other direction in

the horizontal plane;

For each level, the centres of mass and the centre of stiffness

are different, and they may or may not be on the same vertical line;

In the centre of mass of each floor, three DDOFs are

considered: two translations, uxand uyand a rotation about the vertical

axis, u.

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