Innovated Technological Trends in Highways. Flood Modelling & Evaluation of Impacts on Infrastructure

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1 Innovated Technological Trends in Highways Flood Modelling & Evaluation of Impacts on Infrastructure

2 Dr. Waheed Uddin Professor and Director CAIT University of Mississippi Contributions from: CAIT and NCCHE staff Pelican Island Bridge U.S. Department of Transportation Funded NCITEC University Research Project Disaster Protection of Transport Infrastructure and Mobility Using Flood Risk Modeling and Geospatial Visualization 2

3 CAIT Research Projects Students from 18 countries 3

4 Flood Destruction of Roadways and Bridges ~ 200 bridges washed away, East coast, 2011 Hurricane Irene Extreme damage, New Jersey Coast, 2012 Hurricane Sandy 4

5 Flood Destruction of Roadways and Bridges Hurricane Irene, 2011 North Carolina Lewis County Bridge, Oregon 5

6 Flood Destruction of Roadways and Bridges Hurricane Katrina, 2005 Mississippi Gulf Coast 6

7 Flood Destruction of Roadways and Bridges I-10 Bridge, Arizona, Aug 2015 I-10 Bridge, Arizona, Aug

8 Objectives Implement computational and geospatial visualization technologies for extreme flood simulations and flood risk mapping. Implement GIS and geospatial planimetric technology to extract built infrastructure features. Use advanced geospatial analysis to extract 3D features of transportation infrastructure. Enhance decision support systems for bridge and highway infrastructure protection from extreme weather related floods and landslide disasters. A 2-D numerical flood modeling software CCHE2D-FLOOD is implemented by the National Center for Computational Hydroscience and Engineering (NCCHE) using the CAIT s infrastructure spatial maps. 8

9 Flood Simulatıon Research Methodology 1. Select study sites in Mississippi. 2. Acquire high-resolution 2 ft (61 cm) imagery for 2-D feature extraction using GeoMedia Pro/ArcGIS geospatial software. 3. Create planimetrics and coordinates of river centerline (CL), cross-sections, highways, rails and other infrastructure assets. 4. Setup geospatial domain for flood simulation software CCHE2D-FLOOD and DSS-WISE. DEM Data Absolute accuracy of elevation of 1.55 m Relative accuracy of elevation of 0.81 m 9

10 Flood Simulatıon Research Methodology 5. Run extreme flood simulations for high-resolution bare ground digital elevation model (DEM). 6. Analyze flood simulation outputs for floodwater vectors and hydrodynamic forces at river CL and cross-sections. 6. Run flood simulations again after incorporating 3D models of highways, rail, airport, and selected buildings. 7. Compare the flood depths, flood velocity and inundation area using simulation results for 10m, 5m, 3m cell size resolutions. 8. Use floodwater simulation results for structural integrity assessment of bridges and pavements. 10

11 Bridges in the Sardis Pilot Site 1. I-55 Bridge (double bridge) 2. Rail Bridge 3. US-51 Bridge Numerous other smaller bridges and culverts. Bridge deck elevation not represented so floodwater passes through freely. 11

12 Flood Depths and Velocities along the Channel Animation of Flood Depth And Flood Velocity along the Observation Profile Channel CL Flow depths up to 10m Flow velocities up to 6m/s 2014 Study of Flood Risk Mapping, Mississippi 12

13 Computational Model Cell size: Flood Simulation Maximum Flood Depth H max (m) 13

14 Extreme Flood Inundation Simulation Infrastructure Feature Hwy 315 Hwy 35 CAIT / NCCHE Sardis Site Maximum Flood Depth Feature Number 14

15 Flood Simulation Results Total area of 31 sq miles (80 km 2 ) was inundated. Total of 24 bridges and 4 buildings were affected by the simulated flood inundation. Floodwater depth at infrastructure locations reached 40 ft (12m). Selected transportation assets were completely inundated with standing floodwater up to 36 ft (11 m) above the feature. The floodwater overflowed as much as ft (4 5 m) above major roads and airfield. 2.6 miles of I-55, 4.9 miles of Rail, 2.9 miles of US-51, 10.6 miles Highway 35 and 3.3 miles of Highway 315 inundated. Structural integrity: I-55 bridge US-51 Bridge 15

16 Scouring of Bridge Piers due to Floodwater Bridge Pier Scour: Colorado State University equation, modified by Richardson (1993): y s = 2.0 K 1 K 2 K 3 y s a a y p Scour depth, in feet Pier width, in feet 0.65 Fr p 0.61 yp y p Flow depth at the upstream of the pier, in feet F p Froude number of the flow upstream of the pier K 2 Coefficient for flow attack angle (depends also on pier length to width ratio (L/a) Fr p = V p gy p K 2 = cos θ + L a si n( θ 0.65 Local Scour Potential, y s for I 55 = m Rail: m US-51: m 16

17 Highway US-51 Bridge on Tallahatchie River Neoprene Bearings (Photo credit: MDOT) 17

18 Impacts of Sımulated Lateral Floodwater Hydrodynamic Forces on US-51 Bridge Superstructure 18

19 F D = C D ρa r (V r 2 Extreme Lateral Floodwater Hydrodynamic Forces 2 V r Floodwater velocity is difficult to estimate; possible from numerical simulation results where, F D = Drag force, lbs C D = Coefficient of drag, 2 ρ = Fluid density, 62.4 pcf A r = Reference area, 135 sq ft (girders), 30 sq ft (slab) V r = Ref floodwater velocity, 9.02 ft/s (3m/s) * Coastal Construction Manual: Principles and Practices of Planning, Siting, Designing, Constructing, and Maintaining Residential Buildings in Coastal Areas. 4 th Ed. FEMA P-55, Volume II. Federal Emergency Management Agency (FEMA). August Accessed March 2,

20 Overturning & Resistance Moments and Factor of Safety (FS) Calculations for US-51 Bridge Calculation of Resisting Moment (Girder and Slab) M r = 1,684,800 lbs ft + 2,025,000 lbs ft = 3,709,800 lbs ft Calculation of Floodwater Overturning Moment (Girder and Slab) M h = 287,721 lbs ft + 23,681 lbs ft = 311,402 lbs ft Calculation of Uplift Moment on Superstructure (Girder and Slab) M fss = 1,543,277 lbs ft Calculation of Total Overturning Moment M h = 311,402 lbs ft + 1,543,277 lbs ft = 1,854,679 lbs ft Calculation of FS against Overturning M r / M h = 3,709,800 lbs ft / 1,854,679 lbs ft =

21 FS against Overturning for US-51 Bridge Scenario 1 Scenario 2 Scenario 3 (No uplift) (Inundation at top of girders)(inundation at top of deck) Single Girder Entire Superstructure Entire Superstructure Fails Recommended FS is 1.5 minimum. At Risk I-10 Bridge, Arizona, Aug

22 Conclusions The flood simulation with the 3m DEM shows floodwater flow 3m above the I-55 highway. The local scour around the 10 ftdiameter I-55 bridge piers in the main channel is estimated as ft. Unless the pier foundations are sufficiently deep and/or appropriate local scour prevention measures are taken, the bridge may be at risk due to excessive scour. A detailed structural integrity analysis of US-51 highway concrete bridge model shows the most critical condition when the factor of safety (FS) is close to 1.5 for the floodwater level at the top of the concrete girders. The difference in Hmax at US-51 bridge is 8% between 2D analysis of CCHE2D-FLOOD and 1D software HEC-RAS. 22

23 Rodovia Presidente Dutra BR 116 Trecho São Paulo Rio de Janeiro 23

24 Rodovia Presidente Dutra BR 116 Trecho São Paulo Rio de Janeiro Safeguarding against floods and landslides Increase the elevation of Bridge decks suficiently higher above the channel water. Install reinforced concrete or polymer composite sheet piles along the road in flood risk areas where floodwater rushes at high speed from the elevated terrain to the highway. 24

25 Closing slide OBRIGADO!!! 25