Seismic Design of Tunnels Mike Wongkaew, PhD, PE, SE Associate Vice President National Tunnel Practice Lead – NW Tuesday 9/10/2019, 3:30 p.m. – 4:15 p.m. Seismic Environment Source: https://earthquake.usgs.gov/hazards/hazmaps/conterminous/index.php#2014 2 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Seismic Performance of Above Ground Structures - Inertia Effects 3 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Seismic Performance of Underground Structures Source: Dean et al (2006), Power et al (1998) 4 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Seismic Effects on Underground Structures – Imposed Deformation Source: Shamsabadi et al (2001) Source: JSCE (2008) 5 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Seismic Effects on Underground Structures – Imposed Deformation Source: JSCE (2008) Source: Iida et al (1996) 6 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Work Flow for Seismic Design of Underground Structures Determine Seismic Evaluate Ground Response Evaluate Underground Environment to Shaking Structure Response to Seismic Shaking • Design Criteria • Ground Failure • Seismic design loading • Maximum Design • Liquefaction criteria Earthquake (MDE) • Slope instability • Loading criteria for • Operating Design • Fault displacement MDE Policy Earthquake (ODE) • Ground Shaking and • Loading criteria for • Seismic Hazard Deformation ODE Analysis • Longitudinal • Underground Structure • Deterministic SHA extension/compressi Response to Ground • Probabilistic SHA on Deformation • Ground Motion • Longitudinal bending • Free-Field Deformation Parameters • Racking / Ovaling Approach • Acceleration, Seismology velocity, • Soil-Structure displacement Interaction Approach Tunnel Structural Tunnel Engineering • Response spectra, • Special Seismic Design motion time history Issues • Spatial incoherence Geotechnical Earthquake Engineering of ground motion 7 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Determine Seismic Environment Determine Seismic Evaluate. DesignGround Response return periods for recentEvaluate major Underground mass transit Environment to Shaking Structure Response to projects: Seismic Shaking MDE = 2,500 years (4% in 100 years) • Design Criteria • Ground Failure • Seismic design loading ODE = 150 years (50% in 100 years) • Maximum Design • Liquefaction criteria Earthquake (MDE) • Slope instability • Loading criteria for • Operating Design • Fault displacement MDE Policy Earthquake (ODE) • Ground Shaking and • Loading criteria for • Seismic Hazard Deformation ODE Analysis • Longitudinal • Underground Structure • Deterministic SHA extension/compressi Response to Ground • Probabilistic SHA on Deformation • Ground Motion • Longitudinal bending • Free-Field Deformation Parameters • Racking / Ovaling Approach • Acceleration, Seismology velocity, • Soil-Structure displacement Interaction Approach Tunnel Structural Tunnel Engineering • Response spectra, • Special Seismic Design motion time history Issues • Spatial incoherence Geotechnical Earthquake Engineering of ground motion 8 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Determine Surface Ground Motion Parameters - Acceleration Source: https://earthquake.usgs.gov/hazards/hazmaps/conterminous/index.php#2014 9 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Determine Surface Ground Motion Parameters – Velocity & Displ. Source: FHWA-NHI-09-010 Road Tunnel Manual (2009) 10 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Evaluate Ground Response to Shaking Determine Seismic Evaluate Ground Response Evaluate Underground Environment to Shaking Structure Response to Seismic Shaking • Design Criteria • Ground Failure • Seismic design loading • Maximum Design • Liquefaction criteria Earthquake (MDE) • Slope instability • Loading criteria for • Operating Design • Fault displacement MDE Policy Earthquake (ODE) • Ground Shaking and • Loading criteria for • Seismic Hazard Deformation ODE Analysis • Longitudinal • Underground Structure • Deterministic SHA extension/compressi Response to Ground • Probabilistic SHA on Deformation • Ground Motion • Longitudinal bending • Free-Field Deformation Parameters • Racking / Ovaling Approach • Acceleration, Seismology velocity, • Soil-Structure displacement Interaction Approach Tunnel Structural Tunnel Engineering • Response spectra, • Special Seismic Design motion time history Issues • Spatial incoherence Geotechnical Earthquake Engineering of ground motion 11 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Ground Shaking and Deformation – Seismic Waves Evaluate Ground Response Evaluate Underground to Shaking Structure Response to Seismic Shaking • Ground Failure • Seismic design loading • Liquefaction criteria • Slope instability • Loading criteria for • Fault displacement MDE • Ground Shaking and • Loading criteria for Deformation ODE • Longitudinal • Underground Structure extension/compressi Response to Ground on Deformation • Longitudinal bending • Free-Field Deformation • Racking / Ovaling Approach • Soil-Structure Interaction Approach Tunnel Structural Tunnel Engineering • Special Seismic Design Issues Source: Kawashima Geotechnical Earthquake Engineering 12 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Directions of Seismic Wave Propagation – Design Implications 13 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Free-field Strains and Curvatures - Simplified Harmonic Waves Source: Hashash et al (2001) and St John and Zahrah (1987) 14 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Site Response Analysis (e.g. SHAKE, Opensees, DeepSoil) 15 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Evaluate Underground Structure Response to Seismic Shaking Determine Seismic Evaluate Ground Response Evaluate Underground Environment to Shaking Structure Response to Seismic Shaking • Design Criteria • Ground Failure • Seismic design loading • Maximum Design • Liquefaction criteria Earthquake (MDE) • Slope instability • Loading criteria for • Operating Design • Fault displacement MDE Policy Earthquake (ODE) • Ground Shaking and • Loading criteria for • Seismic Hazard Deformation ODE Analysis • Longitudinal • Underground Structure • Deterministic SHA extension/compressi Response to Ground • Probabilistic SHA on Deformation • Ground Motion • Longitudinal bending • Free-Field Deformation Parameters • Racking / Ovaling Approach • Acceleration, Seismology velocity, • Soil-Structure displacement Interaction Approach Tunnel Structural Tunnel Engineering • Response spectra, • Special Seismic Design motion time history Issues • Spatial incoherence Geotechnical Earthquake Engineering of ground motion 16 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Underground Structure’s Response to Ground Deformation Evaluate Underground Structure Response to Seismic Shaking • Seismic design loading criteria • Loading criteria for MDE • Loading criteria for ODE • Underground Structure Response to Ground Deformation • Free-Field Deformation Approach • Soil-Structure Interaction Approach • Special Seismic Design Tunnel Structural Tunnel Engineering Issues 17 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Rectangular Section Source: Wang (1993) 18 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Ratio of Underground Structure Deformation vs Free Field . Tunnel deformation could be up to 2.4x free field deformation . Dependent on stiffness ratio . Additional reference for circular and rectangular sections: − Penzien, 2000, Seismically Induced Racking of Tunnel Linings . Closed form approximation for longitudinal (snaking) deformation 19 12th Annual Breakthroughs in Tunneling Short Course – Seismic Design of Tunnels and Shafts – Mike Wongkaew, PhD, PE, SE Work Flow for Seismic Design of Underground Structures Determine Seismic Evaluate Ground Response Evaluate Underground Environment to Shaking Structure Response to Seismic Shaking • Design Criteria • Ground Failure • Seismic design loading • Maximum Design • Liquefaction criteria Earthquake (MDE) • Slope instability • Loading criteria for • Operating Design • Fault displacement MDE Policy Earthquake (ODE) • Ground Shaking and • Loading criteria for • Seismic Hazard Deformation ODE Analysis • Longitudinal • Underground Structure • Deterministic SHA extension/compressi Response to Ground • Probabilistic SHA on Deformation • Ground Motion • Longitudinal bending • Free-Field Deformation Parameters • Racking