Transcript Major International(Regional) Joint Research Project Joint development of OpenSees and its applications in earthquake-induced disaster evolution of civil infrastructures Zheng He Dalian University of Technology August.

Major International(Regional) Joint Research Project
Joint development of OpenSees and its
applications in earthquake-induced disaster
evolution of civil infrastructures
Zheng He
Dalian University of Technology
August 8, 2013
Key members
CHINA
PI: Prof. Jinping Ou (DUT)
USA
PI: Prof. Stephen Mahin (UCB)
Prof. Mingchu Li (DUT)
Prof. Joel Conte (UCSD)
Prof. Li Chen (THU)
Frank McKenna (UCB)
Prof. Quan Gu (XMU)
Prof. Yang Yang (DUT)
Prof. Gilberto Mosqueda
(UBNY)
Prof. Juan Caicedo (USC)
Part I
Objectives
Part II
Progress Report
Part III
Future Work Plan
Objectives
 Integrating new elements, materials or algorithms into OpenSees
 Improving parallel computing techniques and constructing a high
performance cloud computing platform.
 Developing efficient pre-and post-processing functions for
OpenSees.
 Validation and numerical simulations on disaster evolution
induced by earthquake for building infrastructures.
Interrelationship
2. Computing parallel
processes based on
distributed environment
1. Integrating latest
achievements into
OpenSees
3. Enhancing pre- and
post-processing functions
for OpenSees
4. Numerical simulation of
disaster evolution induced
by earthquake for building
infrastructures
Part I
Objectives
Part II
Progress Report
Part III
Future Work Plan
Evaluation of OpenSees capacity
6
2.5
2
1.5
6
x 10
3
Max Moment: 2000610N*m
Max curvature: 0.0150m-1
Max Moment:2966010N*m
Max curvature: 0.0078m-1
2
1
moment [N*m]
1
moment [N*m]
x 10
0.5
0
0
-1
-0.5
-1
-2
beam E at story 19
-1.5
-2
-0.015
-0.01
-0.005
0
0.005
0.01
beam F at story 4
-3
-8
0.015
-6
-4
-2
0
2
4
6
8
curvature [m-1]
-
curvature [m 1]
-3
x 10
• The Current OpenSees is able to simulate the nonlinear behavior
Max Moment:236910N*m
Max Moment:1950690N*m
of tall buildings
under
strong
earthquake
( e.g., PGA = 1g).
Max curvature: 0.0144m-1
Max curvature:0.0064m-1
6
5
2.5
x 10
2
2
x 10
1.5
1.5
1
• Large displacement-small strain can be simulated by OpenSees.
moment [N*m]
moment [N*m]
1
0.5
0.5
0
• The shear wall model need to be developed / improved in
OpenSees
0
-0.5
-0.5
-1
-1
beam H at story 7
-1.5
beam G at story 32
-1.5
• Pre and post processing need to be developed / improved for
OpenSees.
-2
-0.015
-0.01
-0.005
0
0.005
-
curvature [m 1]
0.01
0.015
-2
-8
-6
-4
-2
0
curvature [m-1]
2
4
6
-3
x 10
1. The Cyclic Softened Membrane Model (Hsu and Mo, 2010) in
Uploaded/improved
elements/materials
OpenSees is improved to increase its numerical stability
Tensile stress
TA
T2
TB
T1
CE
CD' C5'
C4'
TB'
T3
C5
CD
Ec
C4
T3'
T4
T4'
Tensile strain
C6
CC'
CA : ( 0 , D f c' )
CF
CC
C6'
CB : ( cC 2 , f cC' 2 )
CF'
'
'
'
'
CC : ( cC 2   cC
2 , 0.2 f cC 2 );  cC 2  f cC 2 / Ec
C3'
C1
C3
'
CD : ( cC 2  2 cC
2 , 0)
CE : ( cC 5 , f cC' 5 )
C7
'
'
CF : ((2( cC 2   cC
2 )   cC 5 ) / 3, 0.2 f c );  cC 5  0
CG : (0.98 cC 2 , 0.85 f cC' 2 )
C7'
TA : ( cr , f cr )
CG'
C2
TB : ( cT 2 , f cT' 2 )
CG
TC : ( cT 2 / 3, 0.2 f cr )
CB'
CB
TD : (0, 1.5 f cr  0.8 f cT' 2 )
CA
Compressive stress
Cyclic stress-strain
relationship of concrete
Bare steel bar
Stress ( f s )
Steel bar in concrete
25
fy
f
( si , f i )
Stage 2
'
y
250
1000
250
250
50
200
100
50
50
Section A-A
1500
1000
250
Section B-B
300
250
ø10@100
Strain ( s )
ø6/400
A
3ø16
3ø16
2ø16
2ø16
Stage 3
( si 1 , fi 1 )
Cyclic stress-strain
relationship of steel
450
ø6/250
16ø16
B 1000
1900
450
100
0
-100
-200
-30
Test
Analysis
-20
-10
0
10
20
30
Top Displacement (mm)
400
ø10@100
100
A
1500
P
u
400
 y'  y
8ø12
300
Stage 4
1500
Stage 1
300
B
Lateral Force (kN)
Compressive strain
• The concrete constitutive laws include: (1) the softening
effect on the concrete in compression due to the tensile
strain in the perpendicular direction; (2) the softening
effect on the concrete in compression under reversed
cyclic loading; (3) the opening and closing of cracks, which
are taken into account in the unloading and reloading
stages.
• Uniaxial constitutive relationship of mild steel bars
embedded in concrete.
500
Reference：Altin S, Anil O, Kopraman
Y, et al. (2013) Hysteretic behavior of
RC shear walls strengthened with
CFRP strips [J]. Composites: Part B,
44(1): 321-329.
2. A Plane stress J2 model is implemented in OpenSees to
simulate the composite Shear Walls in High-rise buildings
N/4
P
N/4
N/4
N/4
FEM Model
Steel Plate
ø8@100
190
150
2ø10+2ø8
ø6@50
Node
Disp Beam
Column Element
RC wall
ø6@100
100
Shape Steel
(40×40×4)
300
ø6 tie rebar
Steel plate-RC composite shear wall
Steel plate
Quad Element
Components
Element
Material
Concrete：Concrete02
Boundary Parts
Displacement Based
Beam-Column Element
RC wall
Quad Element
Steel：Steel02
CSMM
Lateral loads (kN)
800
400
0
-400
-800
-50
Test
Analysis
-25
0
25
Top displacement (mm)
50
Shanghai
Tower (632m)
The basic conclusions of these composite shear walls include the significant increase of
load carrying capacity and ductility. As well, such composite components exhibit superior
behavior characteristics, particularly with respect to energy dissipation capacity and
damage patter.
Steel Plate
Quad Element
J2 Plasticity
3. A BRB model is developed and implemented in OpenSees
1.5
1.5
Non dissipative
elastic segments
1.0
Ld
BRB1 / y0
Dissipative
elastoplastic
segment
BRB1 / y0
1.0
0.5
0.0
-1.0
-1.5
-1.0
0
pl,BRB1  100
pl,BRB1  100
-0.2
htot = 4h = 13.6 m
-0.4
-0.6
0.01
30
0.5
0.0
-0.5
-1.0
-1.5
Chi-Chi
0
-0.8
20
0
-2.0
Northridge
10

1.0
0.0
0
-0.01
0.01

0.2
Chi-Chi
-2.0
-0.02
Northridge
-1.5
-0.01
BRB element.
0.0
-0.5
-0.5
Ly
0.5
40
10
20
30
40
time (s)
time (s)
h = 3.4 m
Stress-strain cycles (upper figures) and plastic strain (lower
figures) of the left BRB at ground floor under the two
selected accelerograms.
b = 8.0 m
4-storey model with bracing system and equivalent column
Reference: ZONA, A., DALL’ASTA, A., “Elastoplastic model for steel buckling-restrained braces”, Journal of
Constructional Steel Research, Vol. 68, No. 1, January 2012, pp. 118-125.
4. A 3D Cap concrete model is implemented in OpenSees
Cap Model
Concrete
element
 Response of point 1、2、
3、4 under seismic action
Reference: Hofstetter, G., Simo,
J. C., and Taylor, R. L. (1993). “A
Modified Cap Model: Closest
Point Solution Algorithms.”
Comp. & Structures, Vol. 46, No.
2, 203-214.
4. A 3D Cap concrete model is implemented in OpenSees
 Compute response of a dam based on OpenSees under the seismic action
(El-centro)
4
x 10
7
4
x 10
7
B
A
2
2
|S| (Mpa)
4
x 10
5
10
7
0
-5
15
7
x 10
4
C
2
0
-5
Numerical model
0
|S| (Mpa)
0
-5
0
5
I1 (Mpa)
10
15
7
x 10
x 10
0
5
10
7
15
7
x 10
D
2
0
-5
0
5
I1 (Mpa)
10
15
7
x 10
 Response of point A、B、C、D under the seismic action
(El-centro)
Reference: Hofstetter, G., Simo, J. C., and Taylor, R. L. (1993). “A Modified Cap Model: Closest Point
Solution Algorithms.” Comp. & Structures, Vol. 46, No. 2, 203-214.
GUI for OpenSees (DONAP)
1. Enhancements in preprocessing
• Provide several different types of modeling wizards
• Provide multiple structure templates to meet the quick and
convenient modeling requirements
• Provide efficient model editing operations including editing ,
removing, moving the node and line objects, etc.
• Picking up functions
• Multiple viewports of 2D/3D
GUI for OpenSees (DONAP)
2. Enhancements in post-processing
• Provide a variety of different types of visualization method
• Provide intelligent visualization parameter settings by feature
analysis
• “Focus + Context” strategy to highlight important internal
structures
• Picking functions
• Multiple views
GUI for OpenSees (DONAP)
2. Enhancements in post-processing
GUI for OpenSees (DONAP)
3. Scripts and GUI
• Two-way interaction mechanisms of “WYSIWYG” between scripts and
graphical user interfaces
From GUI to scripts
From scripts to GUI
GUI for OpenSees (DONAP)
4. An example of 32-story RC frame building
FE model
Acceleration(UNIT:m/s2)
• Tested by Prof. Gu at Xiamen University
Displacement (UNIT:m)
Part I
Objectives
Part II
Progress Report
Part III
Future Work Plan
2014
·Inform THU for possible improvement their OpenSees GUIDONAP
2015
·Set up and study the real tall building model using DONAP
developed by THU
2016
Test and verify the stability and efficiency of the developed
code
·Upload other newly developed elements /materials /
algorithms, and write technical reports and papers
2017
2013—2017
Help the developers translating and uploading their codes
2013
Find advance achievements in Major Research Plan projects,
and provide uploading requirement to the developers
2013
1.
Integrating
2014
·Construct cloud platform, research the partition method of
reducing the communication of parallel processes
2015
·Apply and improve the parallel simulation of OpenSees on
cloud computing platform.
2016
·Research the implement method of OpenSees’ parallel
interface in cluster
·Integrate the different computing resources by grid, and
research the method of OpenSees to be applied on it.
2017
2013—2017
·Construct the cluster environment, and test the parallel
interface of OpenSees on single process in parallel envir.
2013
·Study the parallel interface of OpenSees and help to
implement the partition method of parallel tasks.
2013
2.Parallel
computing
2014
·Develop visualization functions for OpenSees, including
surface shading, displacement deformation animation, etc.
2015
2013
·Develop modeling capabilities, including multiple types of
modeling wizards and multiple structure templates
·Explore the bilateral interaction mechanism of scripts and
graphical user interfaces
2016
·Design and implement the framework of pre-/postprocessing module
·Further improve the pre-/post-processing modules in
quality and speed. Test, fix bugs and get feedback from users
2017
2013—2017
3.Pre-/postprocessing
·Figure out the practical methodology of multi-scale
modeling, and update the element removal criteria
2014
·Evaluate the capacity of switching, management and
storage of data considering the dual nonlinear
·Verify the stability of the model, element and algorithm in
the environment of large scale computation
2016 2015
·Investigate the influence of failure criteria, element removal
algorithm on the structure global response
·Numerical simulation of the super high rise and super large
space structures
2017
2013—2017
Simulation
2013 2013
·Research on the failure mechanism of high-rise building and
large space structure subjected to 3D strong ground motion
4.
Thank you for your attention
Questions?