Tohoku Tsunami Survey

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 2 N-S
Transect 1 E-W

Transect 1 E-W
— : MSL; — : sea level at tsunami arrival (-40cm)
— : u; — : v; — : sqrt(u 2 +v 2 )
x = 0m
x = 100m
x = 200m
x = 300m
x = 400m
x = 500m
x = 600m
x = 700m
x = 800m

Transect 2 N-S
— : MSL; — : sea level at tsunami arrival (-40cm)
— : u; — : v; — : sqrt(u 2 +v 2 )
x = 0m
x = 150m
x = 300m
x = 450m
x = 600m
x = 750m
x = 900m
x = 1050m
x = 1200m
x = 1350m

Case Studies for Evaluation of
Tsunami Loads and Effects
• 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

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
• 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.
• Video shows outflow between Marine
Pal buildings at 7.5 to 8.5 m/s.
Concrete
Building
5.5 < v < 7.5 m/s
Steel
Building
Marine Pal
Buildings
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.

Sendai - Bore Strike on R/C Structure
Minami Gamou STP Video
Minami Gamou Wastewater Treatment Plant - subjected to direct bore impact

Bore Strike on R/C Structure
Minami Gamou Wastewater Treatment Plant - subjected to direct bore impact
Lidar Scan of deformed shape
Structural drawings obtained from the
Wastewater Treatment Plant
Minami Gamou STP

Bore Strike on R/C Structure
Interior view of 2-story wall
Lidar scan of 2-story wall
Minami Gamou Wastewater Treatment Plant

NEESR - Structural Loading
Direct Bore Impact on Solid Wall
Solitary Wave Breaking on Submerged Reef Crest

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
F
w
1 2
⎛ 2
4
3
3
= ρ ⎜ + +
1
sw
ghb
h
jv
j
g ( hjv
j
)
⎝ 2
⎞
⎟
⎠

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
h j = 5.5m
v j = 6.5m/s
F
w
1 2
⎛ 2
4
3
3
= ρ ⎜ + +
1
sw
ghb
hjv
j
g ( hjv
j
)
⎝ 2
⎞
⎟
⎠
d s = 0.5m
h b =h j +d s = 6.0m

Bore Impact Forces – Minami Gamou
1600
Wastewater Treatment Plant
1400
Maximum Force for 3x Hydrostatic Pressure
Base Shear (kN) (per unit width of wall)
1200
1000
800
600
400
200
First Yield at Edge of Wall
First Yield of Ends of Roof Beams &
First Yield at Midspan of Columns
First Yield at Midheight of Wall
First Yield of Beam at Ends of Wall &
First Yield at Base of Wall
First Yield of Columns at Base of Wall
Maximum Force for OCADI Pressure
Maximum Force for Theoretical Bore Pressure
0
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
Maximum Transverse Wall Displacement (m)

FEA compared with Lidar scan
(m) 0.0 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.0 1.10 1.20 1.30
Minami Gamou Wastewater Treatment Plant - subjected to direct bore impact

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

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
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

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