Post-Disaster Structural Data Collection Following the Tohoku Tsunami
Ian N. Robertson
University of Hawaii at Manoa
Post-Disaster Structural Data Collection Following the Tohoku Tsunami
PI: Ian Robertson, University of Hawaii Collaborative PI: Michael Olsen, Oregon State Univ. The objective of this NSF-funded RAPID project was to perform detailed structural and LiDAR surveys of selected structures and surrounding topography for use in future time-history tsunami modeling of inundation and validation of non-linear structural response analysis.
Major Outcomes 1) Validation of NEOWAVE tsunami inundation modeling. 2) Validation of hydrodynamic loading expressions
developed in laboratory experiments. 3) Contribution to development of tsunami design
guidelines for use in future US design codes.
LiDAR Data Collection
• 4 billion points collected for topography and structures
• Topography maps of Sendai, Onagawa and Rikuzentakata
• LiDAR scans of numerous structures available for detailed tsunami loading analysis
Compiled 3-D LiDAR scan of Onagawa, Japan
NEOWAVE Tsunami Simulation
Kwok Fai Cheung and Yoshiki Yamazaki at UH High resolution tsunami modeling from source to
inundation Shock capturing scheme to model wave breaking
and bore formation First Place at international competition at OSU
NEOWAVE Flow Depth - Onagawa
NEOWAVE Flow Velocity - Onagawa
Transect 1 E-W
Transect 2 N-S
Transect 1 E-W
— : u; — : v; — : sqrt(u2+v2)
x = 0m
x = 100m
x = 200m
x = 300m
x = 400m
x = 500m
x = 600m
x = 700m
x = 800m
— : MSL; — : sea level at tsunami arrival (-40cm)
Transect 2 N-S
— : u; — : v; — : sqrt(u2+v2)
x = 0m
x = 150m
x = 300m
x = 450m
x = 600m
x = 750m
x = 900m
x = 1050m
x = 1200m
x = 1350m
— : MSL; — : sea level at tsunami arrival (-40cm)
Select structures or structural elements based on observed damage and likely cause
Determine estimates of flow depth and velocity Complete structural failure only indicates that
loads exceeded the capacity Undamaged buildings show potential for
success, but only indicate that capacity was greater than loads
Particularly interested in near-collapse or partial failure case studies
Case Studies for Evaluation of Tsunami Loads and Effects
Lateral Loading on Walls - Japan
Onagawa reinforced concrete fish storage building
Hydrodynamic lateral load Measure wall dimensions,
reinforcement layout and take samples of rebar and concrete
Onagawa Outflow
Marine Pal Buildings
Concrete Building
• Pressurized by flow stagnation. • Wall reinforcing tested to be JIS G3112 Grade SD 390. • The taller wall rupture occurred when the return flow ≥ 5.5 m/s. • Other shorter walls do not yield and so v < 7.5 m/s.
Steel Building
• Video shows outflow between Marine Pal buildings at 7.5 to 8.5 m/s.
5.5 < v < 7.5 m/s
7.5 < v < 8.5 m/s
Evaluation of Structural Response Steel-framed Building
Onagawa steel framed building near collapse Measure all member sizes and overall dimensions Note damage caused during drawdown – building
leaning towards ocean
Onagawa Built Environment Captured with LiDAR
NSF Rapid grant - funding for LiDAR survey of selected buildings and topography
Surveys directed by Michael Olsen of OSU and Lyle Carden of Martin & Chock
Onagawa Three-Story Steel Building Frame Survival
Three-story steel moment-resisting frame exposed to 8 m/s outflow estimated from video analysis.
At about 67% blockage of the original enclosure (33% open), the return flow is sufficient to yield the top of the second story columns with 30-cm drift of third floor (First story column is stronger section.)
Fully clad building would have collapsed. Loss of cladding reduced the building’s projected area.
LiDAR scan shows final 50-cm third floor drift.
Minami Gamou Wastewater Treatment Plant - subjected to direct bore impact
Minami Gamou STP Video
Sendai - Bore Strike on R/C Structure
Minami Gamou Wastewater Treatment Plant - subjected to direct bore impact
Bore Strike on R/C Structure
Minami Gamou STP
Lidar Scan of deformed shape
Structural drawings obtained from the Wastewater Treatment Plant
Bore Strike on R/C Structure
Minami Gamou Wastewater Treatment Plant
Interior view of 2-story wall Lidar scan of 2-story wall
Solitary Wave Breaking on Submerged Reef Crest
NEESR - Structural Loading Direct Bore Impact on Solid Wall
NEESR – Development of Performance Based Tsunami Engineering, PBTE
NEESR – Development of Performance Based Tsunami Engineering, PBTE
Hydrodynamic Force on Wall due to Bore Impact
Based on conservation of mass and momentum
++= 3
43
1 )(21 22
jjjjbsww vhgvhghF ρ
Wall load expression comparison with experimental data
Velocity Analysis
Video rate of 30 fps Time from Frame 260 to 316 = 1.87 sec. Distance between buildings = 12.2 m Bore velocity = 12.2/1.87 = 6.5 m/s Jump height approx. 5.5m over approx. 0.5m standing water
Bore Impact Forces – Minami Gamou Wastewater Treatment Plant
Comparison with Different Bore Pressures used in Japan Tsunami Standards
++= 3
43
1 )(21 22
jjjjbsww vhgvhghF ρ
hj = 5.5m
ds = 0.5m
hb=hj +ds = 6.0m
vj = 6.5m/s
Bore Impact Forces – Minami Gamou Wastewater Treatment Plant
0
200
400
600
800
1000
1200
1400
1600
0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 1.10 1.20
Base
She
ar (k
N) (
per u
nit w
idth
of w
all)
Maximum Transverse Wall Displacement (m)
First Yield of Columns at Base of Wall
First Yield at Edge of Wall
First Yield of Beam at Ends of Wall & First Yield at Base of Wall
First Yield at Midheight of Wall
First Yield of Ends of Roof Beams &First Yield at Midspan of Columns
Maximum Force for 3x Hydrostatic Pressure
Maximum Force for OCADI Pressure
Maximum Force for Theoretical Bore Pressure
Minami Gamou Wastewater Treatment Plant - subjected to direct bore impact
FEA compared with Lidar scan
0.0 0.10 (m) 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.0 1.10 1.20 1.30
ASCE 7-10 Minimum Design Loads for Buildings and Other
Structures Minimum Design Loads for Buildings and Other Structures Chap 1 & 2 – General and load combinations Chap 3 - Dead, soil and hydrostatic loads Chap 4 - Live loads Chap 5 - Flood loads (riverine and storm surge) Chap 6 - Vacant Chap 7 - Snow loads Chap 8 - Rain loads Chap 10 - Ice loads Chap 11 – 23 - Seismic Design Chap 26 – 31 - Wind Loads
Proposed ASCE 7-16
Minimum Design Loads for Buildings and Other Structures Chap 1 & 2 – General and load combinations Chap 3 - Dead, soil and hydrostatic loads Chap 4 - Live loads Chap 5 - Flood loads (riverine and storm surge) Chap 6 – Tsunami loads and effects Chap 7 - Snow loads Chap 8 - Rain loads Chap 10 - Ice loads Chap 11 – 23 - Seismic Design Chap 26 – 31 - Wind Loads
ASCE 7 Sub-committee on Tsunami Loads and Effects
Formed in January 2011
16 voting and 12 associate members
Chaired by Gary Chock, S.E., Martin & Chock Inc.
3 meetings per year thus far with draft document now
in development
6.1 General Requirements 6.2 Definitions 6.3 Symbols and Notation 6.4 General Tsunami Design Criteria 6.5 Procedures for Tsunami Hazard Assessment 6.6 Procedures for Tsunami Inundation Analysis 6.7 Design Parameters for Tsunami Flow over Land 6.8 Design Procedure for Tsunami Inundation 6.9 Hydrostatic Loads 6.10 Hydrodynamic Loads 6.11 Impact Loads 6.12 Foundation Design 6.13 Structural countermeasures for reduced loading on buildings 6.14 Special Occupancy Structures 6.15 Designated Nonstructural Systems (Stairs, Life Safety MEP) 6.16 Non-building critical facility structures C6 Commentary and References
Proposed Scope of the ASCE Tsunami Design Provisions 2016 edition of the ASCE 7 Standard, Minimum Design Loads
for Buildings and Other Structures
6.1 General Requirements 6.2 Definitions 6.3 Symbols and Notation 6.4 General Tsunami Design Criteria 6.5 Procedures for Tsunami Hazard Assessment 6.6 Procedures for Tsunami Inundation Analysis 6.7 Design Parameters for Tsunami Flow over Land 6.8 Design Procedure for Tsunami Inundation 6.9 Hydrostatic Loads 6.10 Hydrodynamic Loads 6.11 Impact Loads 6.12 Foundation Design 6.13 Structural countermeasures for reduced loading on buildings 6.14 Special Occupancy Structures 6.15 Designated Nonstructural Systems (Stairs, Life Safety MEP) 6.16 Non-building critical facility structures C6 Commentary and References
Proposed Scope of the ASCE Tsunami Design Provisions 2016 edition of the ASCE 7 Standard, Minimum Design Loads
for Buildings and Other Structures
6.1 General Requirements 6.2 Definitions 6.3 Symbols and Notation 6.4 General Tsunami Design Criteria 6.5 Procedures for Tsunami Hazard Assessment 6.6 Procedures for Tsunami Inundation Analysis 6.7 Design Parameters for Tsunami Flow over Land 6.8 Design Procedure for Tsunami Inundation 6.9 Hydrostatic Loads 6.10 Hydrodynamic Loads 6.11 Impact Loads 6.12 Foundation Design 6.13 Structural countermeasures for reduced loading on buildings 6.14 Special Occupancy Structures 6.15 Designated Nonstructural Systems (Stairs, Life Safety MEP) 6.16 Non-building critical facility structures C6 Commentary and References
Proposed Scope of the ASCE Tsunami Design Provisions 2016 edition of the ASCE 7 Standard, Minimum Design Loads
for Buildings and Other Structures
6.1 General Requirements 6.2 Definitions 6.3 Symbols and Notation 6.4 General Tsunami Design Criteria 6.5 Procedures for Tsunami Hazard Assessment 6.6 Procedures for Tsunami Inundation Analysis 6.7 Design Parameters for Tsunami Flow over Land 6.8 Design Procedure for Tsunami Inundation 6.9 Hydrostatic Loads 6.10 Hydrodynamic Loads 6.11 Impact Loads 6.12 Foundation Design 6.13 Structural countermeasures for reduced loading on buildings 6.14 Special Occupancy Structures 6.15 Designated Nonstructural Systems (Stairs, Life Safety MEP) 6.16 Non-building critical facility structures C6 Commentary and References
Proposed Scope of the ASCE Tsunami Design Provisions 2016 edition of the ASCE 7 Standard, Minimum Design Loads
for Buildings and Other Structures
6.1 General Requirements 6.2 Definitions 6.3 Symbols and Notation 6.4 General Tsunami Design Criteria 6.5 Procedures for Tsunami Hazard Assessment 6.6 Procedures for Tsunami Inundation Analysis 6.7 Design Parameters for Tsunami Flow over Land 6.8 Design Procedure for Tsunami Inundation 6.9 Hydrostatic Loads 6.10 Hydrodynamic Loads 6.11 Impact Loads 6.12 Foundation Design 6.13 Structural countermeasures for reduced loading on buildings 6.14 Special Occupancy Structures 6.15 Designated Nonstructural Systems (Stairs, Life Safety MEP) 6.16 Non-building critical facility structures C6 Commentary and References
Proposed Scope of the ASCE Tsunami Design Provisions 2016 edition of the ASCE 7 Standard, Minimum Design Loads
for Buildings and Other Structures
ASCE 7 Sub-committee on Tsunami Loads and Effects
Committee balloting scheduled for summer 2013, then
transfer to ASCE 7 Main Committee
If adopted, will become Chapter 6 of ASCE 7-16
Will then be referenced by IBC 2018
Arigato Gosai Mas Any Questions?
Tampered sign at Waikaloa Resort, Kona, Hawaii