Summary Overland Flow Alluvial Channels Sediment transport  
Surface runoff  Resistance to Flow Mudflows    
Upland Erosion Local Scour  



 

     Research Projects

     Pierre Y. Julien

Professor of Civil Engineering
Engineering Research Center
Colorado State University
Fort Collins, CO 80523

Tel: (970)-491-8450
Fax: (970)- 491-7008
Email: pierre@engr.colostate.edu





  Summary

Dr. Julien has more than 20 years of experience in the field of sediment transport and river engineering.  He started his academic career as Substitute Professor at the Civil Engineering Department at Laval University in 1979.  He completed his Ph.D. at Laval University in the field of hydraulics and sediment transport.  He pursued post-doctoral studies at the Department of Civil Engineering at Colorado State University in 1983 where he was Faculty Affiliate (1983-1985), Assistant Professor (1985-1989), Tenured Associate Professor (1989-1994), and Tenured Full Professor since 1995. Dr. Julien authored more than 225 scientific publications including two textbooks and at least 50 refereed journal publications.  Under his guidance, 22 Ph.D. and 21 M.S. students completed their graduate degrees in Civil Engineering.  He is currently member of 10 professional organizations.  He has carried out research activities exceeding $3 millions for more than 20 different professional organizations and governmental agencies. 

This web site describes several research projects that Dr. Julien has worked on over the years.  The site has been prepared to share technical information with the scientific community.  The user should find a brief description and a few illustrations, whenever possible, of the research projects.  In most cases, scientific publications can be downloaded.  In some cases, data sets, software programs, demos and calculation procedures are made available.
 

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  Overland Flow 

Research on overland flow has started in Canada as my part of my own thesis and dissertation topics.  More recent research on overland flow has been funded by ARO and ARL since 1986.  Some of the papers below refer to the overland flow characteristics from raindrop impact to sheet flows, roll waves and the applicability of simplified equations of motion.  The second part relates to various numerical models that have been developed over the years. 

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  Surface runoff modeling

Surface runoff modeling has been the emphasis of our activities within the Center for Geosciences.  This on-going project has been funded by ARO and ARL since 1986.  We have developed numerical algorithms for the simulation of rainfall-runoff using GIS terrain data, raingages and/or radar rainfall precipitation.  The model CASC2D has been developed at CSU by Dr. Julien in collaboration with numerous students including Drs. Bahram Saghafian, Fred Ogden, Bill Doe, Darcy Molnar, Amit Sharma, Billy Johnson, and Jeff Jorgeson, who completed their Ph.D. studies at CSU.  The most recent version of the model is CASC2D-SED which simulates soil erosion from overland flow and routes sediment by size fractions to the outlet of a watershed.  Rosalia Rojas is pursuing new developments with the model CASC2D-SED is under further development to determine the effect of grid size in the calculations of soil erosion.  This web site contains numerous papers and descriptions of the models developed at CSU.

    Papers on the model CASC2D

    • Paper describing the model CASC2D  , with Bahram Saghafian and Fred Ogden - Color Figures
    • Brochure with synopsis of CASC2D
    • Demo of the model CASC2D - 185KB Zip file, extract and run CASC2D.exe, press enter three times

    • Posters #1 , #2 

      Papers on spatial and temporal variability
       

    • Similarity and length scale of overland flow  with the 1-D finite element model model CASC, with Glenn Moglen
    • Suitability of simplified overland flow equations, with Jerry Richardson
    • Runoff plane and small basin scale, with Fred Ogden
    • Stationary rainstorms, with Bahram Saghafian and Fred Ogden
    • Moving rainstorms, with Jerry Richardson and Fred Ogden
    • Timeto equilibrium, with Bahram Saghafian
    • Rainstorms - Eulerian and Lagrangian, with Don May 
    • Land-use impact, with Bill Doe
    • Flashflood forecasting, with Darcy Molnar, Billy Johnson and Phil Combs
    • Grid-size effects, with Darcy Molnar

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      Papers on radars
       

    • Radar resolution,  with Fred Ogden
    • Power point files from Jeff Jorgeson showing CASC2D applications with NEXRAD radar data on Cave Creek, Arizona
    • Power Point Presentation using CASC2D-SED and radars with Rosalia Rojas

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      Papers on sediment transport and the model CASC2D-SED
       

    • Model CASC2D-SED,with Billy Johnson and Darcy Molnar
    • Upland erosion using GIS, with Darcy Molnar

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  Upland Erosion

Research on upland erosion has started in Canada as my part of my own thesis and dissertation topics.  More recent research on overland flow has been funded by ARO and ARL since 1986.  Some of the papers below refer to the modeling with CASC2D-SED and the transfroms for the analysis of flow and sediment duration curves.  The most recent version of the model is CASC2D-SED which simulates soil erosion from overland flow and routes sediment by size fractions to the outlet of a watershed.  Rosalia Rojas is pursuing new developments with the model CASC2D-SED is under further development to determine the effect of grid size in the calculations of soil erosion.  This web site contains numerous papers and descriptions of the models developed at CSU.

    • Sediment transport capacity of overland flow, with Daryl Simons
    • Modeling of rainfall erosion, with marcel Frenette
    • LAVSEDI -Model for suspended load in northern stream, with Marcel Frenette
    • LAVSEDII- Model for suspended load in northern streams, with Marcel Frenette
    • Modeling soil erosion and sediment yield, with Marcel Frenette
    • Soil erosion from rainfall depth, Part I, with Abdulhakim Dawod
    • Soil erosion from rainfall depth, Part II, with Abdulhakim Dawod
    • Macroscale analysis of upland erosion, with Marcel Frenette
    • Soil erosion under different climates, with Marta Gonzalez del Tanago
    • Upland erosion modeling with GIS, with Darcy Molnar
    • Computer Modeling of Soil Erosion, with Rosalia Rojas, Keynote Address IAHR-APD Singapore, August 2002

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  Alluvial Channels

This on-going project started during the author's post-doctoral studies and has been recently funded by the USBR since 1996.  We have developed a method for the determination of the downstream hydraulic geometry of alluvial channels.  The research has been carried out in collaboration with J. Wargadalam, Claudia Leon, Travis Bauer and Gigi Richard, who received graduate degrees at CSU.  This web site contains numerous papers and a spreadsheet for the calculation of the hydraulic geometry from the Julien-Wargadalam algorithm. 

  • Alluvial channel geometry method of Julien and Wargadalam, paper
  • Method of Julien and Wargadalam, computer algorithm, Xcel Spreadsheet
  • Secondary flows in the Fall River, with C. Thorne et al.
  • Point bar geometry in narrow sharp bends, with Shigeru Kawai
  • ASCE Task Committee on river width, Part I
  • ASCE Task Committee on river width, Part II
  • Presentation on the Rio Grande at WES
  • Hydrology Days Presentation about the contributions of Stan Schumm to fluvial geomorphology
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  Resistance to Flow and Bedforms

The analysis of resistance to flow and bedforms has been the subject of research in collaboration with Delft Hydraulics and the USBR.  The analysis of bedform geometry and resistance to flow has been the author's research topic during his two sabbaticals in 1991 and 2000.  Research on the Rhine River has been in collaboration with Gerrit Klaassen at Delft Hydraulics.  Additional research at CSU has been carried out by Y. Raslan during the course of his Ph.D degree at CSU. This web site contains a few papers and data sets from recent investigations on the Rhine River.

  • Analysis of dune geometry in large rivers around the world, with G. Klaassen
  • Upper regime plane bed and resistance to flow, with Y. Raslan
  • SABBATICAL:  Julien, P.Y., (2000), "Bed resistance to flow of the Bovenrijn-Waal rivers during the 1998 flood", Delft Hydraulics Report Q 2691, August 2000, 67p. 
  • Word copy of the report: Report 
  • Excel file of the data set: Data 
  • Excel file of key figures: Figures  
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  Local Scour

Research on local scour has been intermittent with interest from USDA for the analysis of rill erosion and interest from FHWA for the analysis of pier scour and scour below drop structures.  The investigations have been performed in collaboration with N.l Bormann, O. Stein, and C. Santoro, who received degrees from CSU.  This web site contains numerous papers and descriptions of the models developed at CSU.

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  Sediment Transport 

This analysis of sediment transport in rivers has been a primary research area since  1977.  First studies relate to sediment transport in canadian rivers in collaboration with marcel Frenette.  Recent investigations refer to the mechanics of sediment transport.  The research results available here refer to the studies in collaboration with  Hyoseop Woo, Junke Guo, and Otto Stein who received graduate degrees from CSU.   This web site contains numerous papers and technical notes on published results.  The analysis of hyperconcentration, mudflows and debris flows is available in a separate item below.

    • Textbook on Erosion and Sedimentation at Cambridge University Press.
    • LAVSED I - Suspended load modeling for northern stream, with M. Frenette
    • LAVSED II - Suspended load modeling for northern stream, with M. Frenette
    • Sediment yield from large watersheds, with M. Frenette
    • Suspension of large concentrations of sands, with H. Woo and E.V. Richardson.
    • Sediment concentration below a free overfall, with O. Stein
    • Analysis of sediment duration curves
    • Sediment transport with the modified log-wake flow functions, with J. Guo
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    Mudflows and Debris Flows

    Research on hyperconcentrations, mudflows and debris flows in mountain streams has been on-going since 1983.  Research has been carried out in collaboration with J. O'Brien, H. Woo, Y. Lan and J. Guo who not only manifested great interest in the topic, but also earned Ph.D. degrees at CSU.  The photos of the recent devastating flows in Venezuela were prepared in collaboration with Claudia Leon and Rosalia Rojas, both curent Ph.D. candidates at CSU.  This web site contains papers and photos of recent debris flows disasters in Venezuela.

       
    • Quadratic formulation for hyperconcentrations, ASCE conf. in Utah, 1985, with J. O'Brien
    • Mudflow properties, with J. O'Brien
    • Suspensions of large concentrations of sands, with H. Woo et al.
    • Rheology of Hyperconcentrations, with Y. Lan
    • Mudflow Model FLO2D, with J. O'Brien and W. Fullerton
    • Kagoshima conference, with J. O'Brien
    • MUDFLOW CONFERENCE PAPER:  Julien, P.Y. and C. Leon, (2000), "Mud floods, mudflows and debris flows - classification, rheology and structural design"  Presented at the Intl. Workshop  n debris flow disaster of December 1999, Caracas, Venezuela. Word copy of the paper: Report 

    • Power Point presentations: Presentation, and other Slides,Field Pictures, and Miscellaneous
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