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In Situ Erosion Evaluation Probe ( ISEEP ). PI: Mo. Gabr North Carolina State University (NCSU) Ph.D. Student: Mohamad Kayser (Graduation 2014) MS Students: Yulian Kebede , Chris Stryffeler , Steven Toebben (Graduation 2014) Cary Caruso and Austin Key (Graduated)
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In Situ Erosion Evaluation Probe (ISEEP) PI: Mo. Gabr North Carolina State University (NCSU) Ph.D. Student: MohamadKayser (Graduation 2014) MS Students: YulianKebede, Chris Stryffeler, Steven Toebben (Graduation 2014) Cary Caruso and Austin Key (Graduated) Summer Interns: YulianKebede - Jackson State University Ian McMillan- The Citadel
Project Overview Scope: Enhancing Capabilities for Rapid Assessment of Erosion/Scour Potential In Situ Erosion Evaluation Probe (ISEEP) • Approach: An in situ process to assess critical erosion/scour parameters: • Threshold Stream Power • Erosion Rate per unit stream power • Motivation: What is available? • Methods to measure scour potential with depth require sample removal and lab testing or only provide surface measurements • Methods for rapid assessment of scourability are lacking in literature
DHS Mission Relevance DHS Mission 5, Ensuring Resilience to Disaster: a tool to assist in fulfilling the DHS mission of infrastructure protection and hazard mitigation • Rapid deployment over a large area to assess incipient erosion of soil profiles supporting protective structures with approaching storm events • Rapid post storm assessment for locating temporary support infrastructures - an important aspects of emergency management • State and Federal government agencies and private consultants can utilize the device data for: i.hazard mitigation, ii. enhanced preparedness, iii.effective emergency response, and iv.rapid recovery: • Frequent measurement of scour potential (i, ii) • Identify scour-critical structures for retrofit and action plan (i, iii) • Provide data to estimate post storm stability and time-dependent stability of critical structures (iii, iv)
Introduction Enhancing Capabilities for Rapid Assessment of Erosion Potential of Critical Structures • Bridges • Dams and Levees • Roads and • Coastal Structures Motivation • The Guardian, 2009
Existing Approaches ISEEP’ Approach Ettema, R., Constantinescu, G. and Melville, B. (2011.)
Existing Approaches Richardson and Davis (2001) K1 = pier nose shape (0.9 and 1.1) K2 = angle of attack of flow (1.0 and 5.0) K3 = state of bed-sediment motion (1.1 and 1.3) Kw = correction factor Vicdx is approach velocity required to initiate scour at the pier for grain size Dx, given by:
Existing Approaches A Better Approach? Erosion Parameters • Assess Erosion Parameters of Soil: • Critical Shear Stress • Detachment Coefficient • Assess Shear Stress with Time • Compute Scour Magnitude and Rate
Technical Approach: ISEEP Component • Cone Tip • Rod Sections • Coaxial Sheathing • Pump • Controller • Water Tank • Generator
GSD of NC-12 Soil Kd’and Pc Field Testing
Field Testing and Modeling Assuming an average flow depth of 0.5 m, a 4.2 m breach is estimated to occur in approximately 1.5 hours for a 4 m/s flow velocity and in 9 hours for 3 m/s flow velocity Field Data Reduction
Modeling of Flow around Bridge Piers • Sand Bed: 24 m long, 20 m wide and 4 m deep • Layers: Two layers soil system • Approach Velocity: 0.45 m/s to 0.9 m/s • Depth of Flow: 1.0 m • Pier Diameter: 1.22 m • 1.5 m 2.5 m 1m 3m 24 m 3m
Pier Scour 3-D Scour Profile
Laboratory Experiments & Field Testing Yulian A. Kebede
Dry weight of mixture: 10% Fines - 90 % sand Initial water content : 18 % - 23 % Lab Testing with Clay-Sand Mixture
Lab Testing Results • kd • 0.017 cm/sec per N/m2 (45 sec) 0.015 cm/sec per N/m2 (60 sec) • Pc • 16 Watts/m2 • Vc • 0.32 m/s • tc • 1.75 Pa
Flow Velocity range of 1.0 m/s to 2.0 m/s (Froude number 0.23 to 0.45) • Pier Diameter = 1 m • Depth of flow = 2 m Ansari et al. (2002) dsmc/dsms = 1.51(C*/φ*)0.2
ERDC Collaboration: Lake Calumet Testing • Located at far south side of Chicago, IL • Largest body of water in the city • Highly contaminated due to years of industrial waste and runoff from nearby land fills • Contains an approximate water depth of 4 ft with a clay layer located about 1cm beneath the water depth
Plan • Collaboration with ERDC in effort to compare and contrast results with that of the Erosion Function Apparatus (EFA) • EFA testing lead by Dr. Joseph Gialani • Scheduled to take place in March/April • ISEEP testing will be performed onsite and the EFA testing will collect sample and perform testing in a nearby testing facility
Next Steps • Validation Modeling of Various Hydraulic Structures resting on soils with fine contents and Storm Conditions • Incorporation of skin friction factor to the data reduction scheme especially at greater penetration depths. • Extend the collaboration work from the lab to the field by performing field tests at sites where scour rates have been established in the past • Process the testing approach and the data reduction scheme for acceptance as ASTM standards
Milestones • Modeling of various types of hydraulic structures resting and assessing applicability of ISEEP for assessment of scour magnitude • Viability of the approach in various types of soils, including soil with fine contents • The refinement of the data reduction scheme with incorporation of factors such as the rods’ skin resistance especially at greater penetration depths • Applicability of the results in view of other existing approaches that require soil sampling
End Users and Translation Activities • Federal Emergency Management Agency (FEMA) • U.S. Army Corps of Engineers (USACE) • State Offices and Agencies of Emergency Management • State Offices of Dam Safety • Standardization of the testing process and data reduction scheme , and submission to Committee D18.02 on “Sampling and Related Field Testing for Soil Evaluations” for review and commenting. • The system is available now and the plan is to test it in cooperation with ERDC CHL as outlined in the proposal. • Transition of ISEEP to government and private sector via commercialization processes –Discussion on incubator for a private company, North Carolina State University office of Technology Transfer.
Products • Media Publicity • Gizmag, November 2010 “Safer levees and bridges thanks to new erosion and scour detector” • ASCE Civil Engineering Magazine, August 2011-Technology Section, Page 40 “Probe Reveals Hidden Potential of Scour,” • Conference Proceedings • Cary Caruso and M. A. Gabr (2010)“In Situ measurement of the scour potential of non-cohesive sediments (ISEP)” Geotechnical Special Publication No. 211, American Society of Civil Engineers (ASCE), pp. 115-125. • Cary Caruso and M. A. Gabr (2011) “In Situ Assessment of Scour Potential with Depth Using Jetting Approach,” Geotechnical Special Publication No. 211, (ASCE), pp.1483-1492. • M. Kayser and M. A. Gabr (2013). “Scour assessment in cohesive soil using ISEEP.” Accepted, International Conference on Soil Mechanics and Geotechnical Engineering, Paris, France, 2013. • Posters • Caruso, C. W., Poster Presentation at DIEM meeting with DHS Under Secretary of S&T , Chapel Hill, NC, Feb 2011. • Caruso, C. W, DHS University Summit Student Day, Washington, DC, Mar., 2011. • Kayser, M. and Gabr, M. “Scour Assessment of Bridge Foundations Using an In Situ Erosion Evaluation Probe (ISEEP)” 92nd Transportation Research Board meeting, Washington DC, January 2013. • Journal Papers • Gabr, M. A., Caruso, C. W., Key, A., and Kayser, M. “Assessment of In Situ Scour Profile in Sand using a Jet Probe,”, Journal paper accepted by ASTM, Geotechnical Testing, in press. • Kayser, M. and Gabr, M. A. “Scour Assessment of Bridge Foundation Using In Situ Erosion Evaluation Probe (ISEEP).” Journal paper accepted by the Journal of the Transportation Research Board, in press. • Masters Thesis and Masters Project • Cary Caruso “In Situ Measurement of the Scour Potential of non-cohesive Sediments “ MS thesis, August , 2011 • Austin Key “ Data Reduction Protocol for Assessment of Erosion Parameters Using ISEP ,” MCE Project. January 2012
Thank You Questions?