Analysis and modelling of the seismic behaviour of high ... - Ingegneria

5. SEISMIC BEHAVIOUR OF RC COLUMNS EMBEDDING STEEL PROFILES
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M [KNm]
900
800
700
600
500
400
300
200
100
Diagram M-N
0
-1500 -1000 -500 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000
N [KN]
Diagram M-N
260 X
302 X
309 X
260 X (II)
302 X (II)
309 X (II)
M-N(-30%)
Figure 5.11. M-N diagram illustrating the column resistance
for the Seismic load combination B (Medium)
For the design of MEDIUM ductility members prescriptions from Eurocode 8 (2001)
have also been taken into account. This means a reduction of 30% in the resisting
moment MRd and an NSd axial force to be not greater than 0,65NRd. Besides, all
necessary prescriptions for both end sections of the primary columns to be
considered as critical regions have been matched (Eurocode 8, 2001).
Moreover, in accordance with the design rules of Eurocode 2 (2001) and Eurocode
8 (2001) the following details for the columns are chosen. Note that for the design
of MEDIUM ductility members also prescriptions of Eurocode 8 (2001) clause have
been taken into account.
• Details of the concrete section designed for the Gravity load combination
Maximum longitudinal hoops spacing 300 mm
Maximum transversal hoops spacing 510 mm
Minimum shear reinforcement ratio ρw 0,0011
Concrete column depth 700 mm
Concrete column width 550 mm
Number of longitudinal rebars along major axis 4
Number of longitudinal rebars along minor axis 4
Longitudinal rebars diameter 16 mm
Longitudinal hoops spacing 300 mm
Hoops diameter 10 mm
Hoops arm number 4
Table 5.3. Geometrical properties of the cross section