modelling of reinforced concrete frames in fires following...
TRANSCRIPT
Modelling of Reinforced Concrete Frames in Fires Following an Earthquake
Mariyana Aida Ab KadirPhD Student
Supervisors : Prof Asif Usmani and Dr Martin Gillie
School of Engineering and Electronics The University of Edinburgh
Earthquake and fire resistant design are two different fields in structuralengineering. Earthquake motion may trigger fires in the damaged structure. As a result the fire resistance of the structure may be significantly impaired.
This research is particularly concerned with the response of reinforced concrete (RC) frames in a fire following an earthquake.
(a) (b)Figure 1 (a) The 1906 San Francisco Earthquake (b) The Famous Maruzen Bookstore after The 1923 Tokyo Earthquake
Introduction
• 2D Finite element beam model
• (B21-Timonshenko Beam-Shear Flexible)
• Material properties of the frame are assigned from EuroCode2-Part 1• Concrete Damaged Plasticity-Concrete Model in ABAQUS
• 7 cycles of lateral displacement are applied at slab level and the lateral reaction at the base of the frame is observed
• The frame is exposed to heating for 1 hour. (at a constant 10000C)
-100-80-60-40-20
020406080
100
0 30 60 90 120 150 180
Time Steps
Displ
acem
ent,U
1 (m
m)
T (oC)
1000
5 60 t(min)
Numerical Modelling
U1
Result Analysis
-20
0
20
40
60
80
100
dmax Free Thermal
Time StepsD
ispl
acem
ent,U
1 (m
m)
Case I
Case II
Case III
-400-350-300-250-200-150-100-50
050
100150200250300350400
-120 -100 -80 -60 -40 -20 0 20 40 60 80 100 120
Displacement,d (mm)
Bas
e Sh
ear,
kN
-100
-80
-60
-40
-20
0
20
40
60
80
100
Loading dmax Free
Time Steps
Dis
plac
emen
t,U1
(mm
)
Case I
Case II
Case III
Hysteresis Curve
Displacement HistoryDisplacement of the frame after the heating
Reaction force of the frame
•There is a reduction in the residual displacement of the frame after heating.
Result Analysis
-400
-300
-200
-100
0
100
200
300
400
Loading Free Thermal
Time Steps
Rea
ctio
n Fo
rce,
kN
Case ICase II
Case III
Future Research
The computational results will be compared with the test results on real frames currently being carried out at IIT Roorkee, India.
REFERENCES• Abaqus: Abaqus Analysis User’s Manual. Providence, Dassault Systemes Simula Corp,2008• EN1992-1-2. Eurocode 2: Design of concrete Structures-Part 1-2: General Action-Actions on Structures Exposed
to Fire, 1999.• Mousavi, S. Bagchi, A. Kodur, V.K.R. Post-Earthquake Fire Hazard to Building structures, Canadian Journal of
Civil Engineering, 35: 689-698, 2008• Scawthon, C., Eidinger J.M. and Schiff, A.J., editors, Fire Following Earthquake, ASCE Publications, 2005.
Frame Test in IIT Roorkee,India