Ralph Rollins, performed geotechnical investigations for over 5000 structures I took Soil Mechanics class from my Father
Rachel Rollins is a Civil Engineering student Rachel took Soil Mechanics class from her Father
Granddaughter, Ella, shows early interest in soil behavior
Post-Earthquake Geotechnical Reconnaissance Studies Kyle Rollins Civil & Environmental Engineering Brigham Young University
EERI Learning From Earthquakes
GEER Team Members in Chile
Travel in Japan after Fukushima failure Carried Geiger counter Radiation less than would be received if we stayed in US
Earthquake Interrupts Earthquake Briefing
Process of Investigation Coordinate/Collaborate with local engineers/researchers 1 st wave: Initial overview of areas of interest by advance team 2 nd wave: Follow-up with second wave to provide more detailed examination of key sites 3 rd wave: Measurement of soil properties in key areas [V s, SPT (N 1) 60, CPT q c, I c, etc.]
Understand the Seismo-Tectonic Setting Magnitude Fault type (Strike-slip, Normal, thrust, Subduction) Distribution of acceleration stations and measured peak accelerations
Tectonic Setting Nazca Plate moving under South America Plate 13 Earthquakes >7.0 since 1973 M9.5 in 1960 largest on record
M = 8.8 Chile Earthquake Hospital in Curico R. Boroschek, Universidad de Chile Large Magnitude Subduction Zone Event Long Duration of Shaking (often > 60 s) Well-Designed Earth Systems Shaken Many Opportunities to Gain Knowledge
Ground motions K-NET: surface (693) Kik-NET: v array (496) BRI: buildings (50) 16 recordings PGA > 1.0 g R rup = 49 to 500 km
Accelerations at K-Net Tsukidate (MYG004 station) (from National Research Institute for Earth Science and Disaster Prevention, NIED, 2011) ~ 50 seconds
M7.6 Samara Zone of Amplification ic ion Costa Rica Peninsula Nicoya Peninsula Earthquake 2012 Fig. 1.1 Location of epicenter and peak ground accelerations measured by the seismic network operated by the Engineering Seismology Laboratory (LIS) at the University of Costa Rica. The recordings are color coded according to the acceleration level and Mercalli scale categories shown at the base of the map (LIS, 2012a).
Understand the Geologic Setting Areas of deep soft soil Areas of saturated loose sand/fill material Areas of rock or stiff soils Basin structure
Understand Surface Geology Relative to Shaking Limon M7.5 2012 Samara Epicenter M7.5 1991 Limon Epicenter Fig. 2.1 - Geology map of Costa Rica (modified from Dutch 2012) with locations of epicenters from M7.5 1991 Limon Earthquake and M7.6 2012 Samara Earthquake Intensity Map Geology Map
What are we looking for?
What are we looking for? Liquefaction Triggering Gravels Silts/Sandy Silts/Clayey sands Magnitude effects on liquefaction Liquefaction Effects Settlement Uplift of utilities Lateral Spreading Residual Strength of liquefied soil Pile downdrag
What are we looking for? Ground Response and Amplification Topographic Amplification Influence of local soil conditions Basin effects Resonance with structural period Comparison of good and bad performance at adjacent sites Influence of ground improvement on performance
What are we looking for? Landslides Slope, acceleration level, duration, etc. Influence of foundation type on performance (shallow vs deep foundations) Performance of utilities/pipelines Performance of levees and dams Behavior of earth retaining systems Performance relative to Tsunami
Mechanics of Liquefaction
Definition of Liquefaction A decrease in strength and stiffness caused by a build-up of water pressure due to earthquake shaking. = ( - u) tan where = vertical stress from soil u = the water pressure tan = the friction coefficient
Where will we find liquefaction? Port facilities Beaches Rivers/bridges Low lying areas with loose fill
Look for sand boils and ejecta indicating liquefaction Photo credit: D. Zekkos, 2014 Cephalonia
Gravel Ejecta after 2008 M7.6 Wenchuan, China Earthquake Photo Credit: Cao et al, 2013
Chinese Dynamic Cone Penetrometer
Gravel Liquefaction Curves
Liquefiable soil
Liquefaction in Adapazari, Turkey Photo credit: USGS Sanchio et al (2004)
Effects on buildings (e.g., Kamisu City) GEER 2011 (photo: Boulanger)
GEER 2011 (photo: K.M. Rollins)
GEER 2011 (photo: Rollins)
Settlement analyses for the Urayasu area Katsumata K &Tokimatsu (2012) 2) AIJ procedures Missing information? Other procedures? Bias & dispersion?
Liquefaction around Pile Supported Ferris Wheel GEER Photo: K.M. Rollins
Building Settlement & Rotation Constructed on 26 m long concrete Piles (3 Rotation) GEER 2011 (photo: K.M. Rollins)
Liquefaction settlement of building on shallow footings Fig. 2.5 Foundations Punching through liquefied ground (a) exterior column, north side; (b) interior column,left behind a 60cm crater.
Shear wave velocity, V s, from Surface Wave Measurements at Liquefaction Site-Costa Rica 2012 Vs profile: R. Luna
Drag Load & Settlement from Liquefaction Applied Load Negative Side Shear Reduced Side Shear Non-Liquefiable Soil Liquefiable Liquefied Soil Bearing Stratum End-Bearing
Juan Pablo II Bridge, Concépcion Bent damage due to lateral spreading on NE approach Liquefaction-induced pier settlements along bridge span Photo taken from NE Lateral spreading N Pier settlement
Juan Pablo II Bridge Liquefaction-induced pier settlements along bridge span Piers # 113-116 Piers # 113-116 0.5m-0.7m Modes of deformation Liquefaction-induced pier settlement
Before earthquake After earthquake
Port of Coronel, South of Concepcion
Lateral Spreading at Puerto Coronel
T. Leslie Youd Emeritus Prof. BYU Bring a tape and a field book, not just a camera!
Lateral Spreading at Puerto Coronel 1.40 Coronel, Chile Port Lateral Spread Cumulative Horizontal Displacement (m) 1.20 1.00 0.80 0.60 0.40 0.20 0.00 Line 1 Line 2 0 5 10 15 20 25 30 Distance from Wall Face (m)
Lateral Spreading Damage - Ports Ground Movement 2010 M8.8 Maule Chile Earthquake
Sketch from field notes
Base Isolated Pier (< 0.5 m offset) Base isolators Stabilizing Pile
Collapse Holes from Lateral Spreading
Collapse Holes from Lateral Spreading
Lateral Spreading at Puerto Coronel
Lateral Spreading at Puerto Coronel Near Port Coronel, Chile Lateral Spread 3 Cumulative Horizontal Displacement (m) 2.5 2 1.5 1 0.5 0 0 20 40 60 80 100 Distance from Wall Face (m)
Fisherman s Pier at Coronel Damaged piles due to lateral spreading Lateral spread measurement line
Lateral Spreading near Puerto Coronel Ground Movement
D=2.8 m (N 1) 60 < 10 D=1.5 m 0<(N 1 ) 60 < 15 D=0.45 m 16<(N 1 ) 60 D= 0 m 20<(N 1 ) 60
Contrasting Performance of Adjacent Piers
Contrasting Performance of Adjacent Structures
Contrasting Performance of Adjacent Structures
Geo-referenced Photographs
Port of Iquique, Chile April 2014
Cone Penetrometer Testing (Donated by ConeTec)
Cone Penetration Test Soundings
Port of Iquique, Chile April 2014
UAVs for Reconnaissance
Identifying unique points from multiple directions
Structure from Motion Point Clouds Kevin Franke, BYU
Structure from Motion Point Clouds
Measured vs. UAV Displacements Cumulative Displacement (m) 2.5 2.0 1.5 1.0 0.5 0.0 Section Through CPT 3, 4 and 5 UAV-CPT 3,4 and 5 North End of Pier UAV North End of Pier 0 10 20 30 40 50 60 Distance from West Base (m)
Passive Force from Lateral Spreading Liquefaction Passive force often drives displacement Selection of smaller passive force (lower K p ) may be unconservative
Lateral Spread of Abutment in bridge Shearing of back wall on beam 35 cm offset in rebar
Lateral Spreading Around Abutment Retaining wall Abutment wall
Lateral Spread Damage-Bridge 1991 Limon, Costa Rica Earthquake
Obtain plans for bridge foundations
176.14 m 24.96 m 75.02 m 75.24 m Rio Estrella Bridge, Costa Rica, 1991
Liquefaction in the Atacama Desert?
Liquefaction in the Desert?
Liquefaction at Tana Bridge
Liquefaction in the Atacama Desert
Lateral Spreading at Puerto Valparaiso Apparent lateral spreading at Berth 5 Lateral displacement and settlement behind dock wall
Lateral Quaywall Movement at Puerto Valparaiso
Lateral Spread at Puerto Valparaiso 60 Valpariso, Chile Port Lateral Spread Cumulative Horizontal Displacement (cm) 50 40 30 20 10 Horizontal Movement 0 0 5 10 15 20 25 30 35 40 Distance from Wall Face (m)
Lateral Spreading at Port of Valparaiso
Juan Pablo II Bridge Lateral spreading and bridge bent damage on NE approach Deck settlement Lateral spread Deck settlement Liquefaction Deck settlement Lateral spread Shear failure Lateral spread evidence of liquefaction
La Mochita Bridge, Concépcion
Site Effects: Vespucio Norte & Ciudad Empresiarial A B Q fno no: Silt & Clay Layers B A Silty Clay, Silty Sand Collapse No collapse Gravel, Sandy gravel Localized Damage Site Effects? H/V peaks: 0.5-2sec (Bonnefoy et al, 2008) Damage to 5 to 20-story buildings
Liquefaction at Strong Motion Sites GEER 2011 (photo: K.M. Rollins)
Strong ground motion stations with liquefaction nearby GEER 2011 (photos: Boulanger)
Station CHB009 Station CHB024 0. 2 0. 1 CHB009 - NS 0. 2 0. 1 GEER 2011 (photos: Boulanger) CHB024 - NS Acceleration ( g) 0 -. 0 1 -. 0 2 0. 2 0. 1 CHB009 - EW 0 -. 0 1 -. 0 2 0. 2 0. 1 CHB024 - EW - 0. 1 0-0. 1 0 -. 0 2 40 80 120 160 200 Time ( s ) -. 0 2 40 80 120 160 200 Time ( s )
Landslides in Steep Slopes/Stiff dry clay West of Arauco
Landslides in Steep Slopes/Stiff dry clay
Bearing Failure and Lateral Spread at Tupul Bridge Bearing failure along highway Lateral spreading impacts bridge abutment Tupul Bridge
Failure of Highway Embankment Embankment Fill Soft Clay Liquefiable Zone Embankment Fill Soft Clay Liquefiable Zone
Skewed Bridge Abutment Overview 40% of 600,000 bridges in US are skewed Current AASHTO design code does not consider any effect of skew on passive force Observations of poor performance of skewed bridges Shamsabadi et al. 2006
Greater Damage to Skew Abutments
Permanent Abutment Offset at Skewed Bridge 3 inch Transverse Displacement 4 inch Longitudinal Displacement
Earthquake Damage to Skewed Bridges (Paine, Chile) Top Bridge Bottom Bridge Top Bridge Top Bridge Bridge decks have rotated and bridge was demolished Bottom Bridge Bridge deck remained was offset in service and was after eventually the earthquake demolished
Damage rate for skewed bridges was twice that of non-skewed bridges (Toro et al 2013)
Field Test Setup - Plan View 4ftDia. Drilled Shaft Sheet Pile Wall Section AZ-18 2 600 kip Actuators 24 ft 22 ft 11 ft wide x 5.5 ft high Pile Cap 12.75 inch Dia. Steel Pipe Piles Transverse Wingwalls 2 x 4 ft Reinforced Concrete blocks
Field Test Setup Elevation View 4ftDia. Drilled Shaft Sheet Pile Wall Section AZ-18 11 ft m wide x 5.5 ft high x 15 ft long Pile Cap 6ft 6.4m 2 600 kip Actuators 12.75 inch Dia. Steel Pipe Piles
No Skew - 0 Test Setup
15 Skew Test Setup
30 Skew Test Setup
Passive Force Reduction Factor vs. Skew Reduction Factor, R skew 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 R skew = 8x10-05 2-0.018 + 1 R² = 0.98 Lab Tests Numerical Analysis Field Tests (This Study) Proposed Reduction Line 0 15 30 45 60 75 90 Skew Angle, [degrees]
Settlement and Sliding of Approach Fills
Settlement and Sliding of Approach Fills
Damage to braced retaining system GEER 2011 (photo: K.M. Rollins)
No Damage Associated with MSE Walls
Highly Corrosive Soil
Sand Compaction Piles (Fudo Tetra)
Typical Installation Arrangement Area Replacement ratio (A r ) of 10% for low fines to 20% for higher fines Sand Pile Non-liquefiable Soil Z/2 Treatment Area Liquefiable Soil Treatment zone, Z Z/2 Building Area Non-liquefiable Soil Elevation View Sand column Plan View Gravel column
Contrast between Tokyo Disney and Urayasu City Liquefaction Space Mount at Tokyo Disney Courtesy Japan Probe Parking Lot at Tokyo Disney Area around structures in Tokyo Disney treated with compaction Piles-little settlement Courtesy Japan Probe Parking lot at Tokyo Disney not treated and experienced 50 cm of settlement
GEER 2011 (photo: K.M. Rollins)
Seismic Performance of Dams & Levees Coihueco Zoned Earth Dam Upstream Slope Failure Levee Breach Rapel Concrete Dam (most dams performed well)
Seismic Performance of Tailings Dams Las Palmas Tailings Dam Failure Approximate area of failure and flow direction
Naruse River left levee at km 11.3 GEER 2011 (photo: L. F. Harder)
Levee Damage in the Tohoku Region (MLIT 2011) Type and Number of Levee Damage Sites Reported River System Failure Settlement Slope Slumping Levee Cracking Revetment/ Wall Damage Gate Damage Other Total Mabuchi 0 1 1 1 5 1 5 13 Kitakami 13 62 47 278 121 67 58 646 Naruse 9 27 25 183 56 26 37 363 Natori 1 2 1 26 2 2 1 35 Abukuma 2 26 16 73 2 10 3 132 TOTAL 25 118 90 561 186 106 104 1190
Tsunami Damage GEER Photo: K.M. Rollins
Car on top of 4 story building
Pile Supported Building vs Tsunami
Rematch
Tips for Sucessful Geotechical Recon Be safe out there Develop friendships during your career Collaborate with local engineers, geologists, seismologists Make use of Google Earth for scouting/reporting Document performance, don t just photograph Use UAVs for topographic mapping Quantify site conditions if possible (Vs, CPT, SPT, DMT) Look for contrasting sites (good/bad performance) Obtain plans where if possible Morning plan of attack, Evening reports