Civil Engineering

David Unger

Faculty Photo

Professor of Mechanical and Civil Engineering
Ph.D, University of Illinois, Theoretical and Applied Mechanics

Koch Center Room 257
812-488-2899
du2@evansville.edu

Dr. Unger is the author of the textbook, Analytical Fracture Mechanics, which was originally published in hard cover by Academic Press (1995), and later reprinted in paperback form by Dover Publications (2001). He was awarded the Sadelle and Sydney Berger Award for scholarly activity by the University of Evansville in 2005, the Dean’s Teaching Award in the College of Engineering and Computer Science in 2006, and designated a UE Global Scholar in 2007. He is a professionally licensed engineer, and has served on the UE faculty for eight years.

Spring 2013 Courses:

  • ENGR 212: Statics
  • ENGR 213: Dynamics
  • ENGR 232: Mechanics of Materials

Education:

  • PhD Theoretical and Applied Mechanics, University of Illinois at Urbana-Champaign.
  • MS Aeronautical and Astronautical Engineering, University of Illinois at Urbana-Champaign.
  • BS Aerospace Engineering, St. Louis University.

Experience:

  • Visiting Associate Professor, Dept of Mechanical Engineering and Engineering Mechanics, Michigan Technological University.
  • Acting Program Director of Mechanical Engineering Technology, Franklin University
  • Assistant Professor of Engineering Mechanics at The Ohio State University.
  • Postdoctoral Researcher, Dept of Chemical Engineering and Materials Science, University of Minnesota.

Specialty Areas:

  • Nonlinear and Environmentally Assisted Fracture Mechanics
  • Solid Mechanics
  • Materials

Publications

Unger, D.J., “Large Plastic Deformations Accompanying the Growth of an Elliptical Hole in a Thin Plate,” Journal of Elasticity, 99, 117-130 (2010).

Unger, D.J., “A Plane Stress Perfectly Plastic Mode I Crack Problem for a Yield Condition Based on the Second and Third Invariants of the Deviatoric Stress Tensor-Part II,” Journal of Mechanics of Materials and Structures, 4, 1651-1656 (2009).

Unger, D.J., “A Plane Stress Perfectly Plastic Mode I Crack Problem for a Yield Condition Based on the Second and Third Invariants of the Deviatoric Stress Tensor-Part I,” Journal of Mechanics of Materials and Structures, 3, 795-807 (2008).

Unger, D.J., “Path Independent Integral for an Elliptical Hole in a Plate under Tension for Plane Stress Deformation Theory,” Journal of Elasticity, 92, 217-226 (2008).

Unger, D.J., “A Complete Perfectly Plastic Solution for the Mode I Crack Problem under Plane Stress Loading Conditions,” ASME Journal of Applied Mechanics, 74, 586-589 (2007).

Unger, D.J.,  "Numerical Plane Stress Elastic - Perfectly Plastic Crack  Analysis under Tresca Yield Condition with Comparison to Dugdale Plastic Strip Model," Mechanics Research Communications, 34, 325-330 (2007).

Unger, D.J., "A Plane Stress Perfectly Plastic Mode I Crack Solution with Continuous Stress Field," ASME Journal of Applied Mechanics, 72, 62-67 (2005).

Unger, D.J. "Continuous Stress Field with Compatible Velocity Field for Plane Stress Perfectly Plastic Mode I Crack, Proceedings of McMat2005, Joint ASME/ASCE/SES Conference on Mechanics and Materials, June 1-3, 2005, in Baton Rouge, LA (LSU).  Invited speaker to technical session commemorating the lifelong contributions of E.C. Aifantis to mechanics and materials research.  Six page summary on CD.

Unger, D.J., "Perfectly Plastic Caustics for the Opening Mode of Fracture," Theoretical and Applied Fracture Mechanics, 44, 82-94 (2005).

Unger, D.J., Invited Contributor:  Problems of Fracture Mechanics and Fatigue, Eds:  Gdoutos, E.E, Rodopoulos, and Yates, J.R., Kluwer Academic Publishers, Dordrecht, 385-401 (2003).

Unger, D.J. and Aifantis, E.C., "A New Class of Solutions of the Reduced Wave Equation Applicable to Crack Problems Related to Gradient Elasticity," Special edition of journal devoted to Fracture and Damage Mechanics (guest ed. E.E. Gdoutos) of Facta Universitatis - Series Mechanics, Automatic Control and Robotics, 3, 599-612 (2003).

Unger, D. J., "Similarity Solution of the Flamant Problem by Means of a One-Parameter Group Transformation," Journal of Elasticity, 66, 93-97 (2002).

Unger, D.J., Analytical Fracture Mechanics, (reprint with addendum), Dover Publications, Mineola, NY (2001).

Unger, D.J. and Aifantis, E.C., "Strain Gradient Elasticity Theory for Antiplane Shear Cracks - Part I: Oscillatory Displacements," Theoretical and Applied Fracture Mechanics, 34, 243-252 (2000).

Unger, D.J. and Aifantis, E.C., "Strain Gradient Elasticity Theory for Antiplane Shear Cracks - Part II: Monotonic Displacements," Theoretical and Applied Fracture Mechanics, 34, 253-265 (2000).

Unger, D.J., "Stress across an Elastoplastic Boundary of a Mode I Crack:  Parabolic to Hyperbolic Plasticity Transition," Theoretical and Applied Fracture Mechanics, 30, 195-208 (1998).

Unger, D.J., "Isostrain Contours for a Plane Stress Mode I Elastoplastic Fracture Problem,"
International Journal of Fracture, 82, R47-R52 (1996).

Unger, D.J. and Aifantis, E.C., "An Analytical Gradient Plasticity Solution for Mode III," International Journal of Fracture, 74, R75-R79 (1996).

Unger, D.J., Analytical Fracture Mechanics, pp. 300, Academic Press, San Diego (1995).

Unger, D.J. and Aifantis, E.C., "The Asymptotic Solution of Gradient Elasticity of Mode III," International Journal of Fracture, 71, R27-R32 (1995).

Unger, D.J., "On the Utility of Inverse Cassinian Oval Coordinates for the Mode III Elastoplastic Fracture Problem," International Journal of Fracture, 63, R59-R63 (1993).
 
Unger, D.J., "A Comparison Between Mode I and Mode III Fracture Assessment Diagrams," International Journal of Fracture, 53, R37-R41 (1992).

Unger, D.J., "An Energy Dissipation Analysis for A Transitional Model of Crack Tip Plasticity,"
Engineering Fracture Mechanics, 41, 457-462 (1992).

Unger, D.J., "Developable Surfaces in Elastoplastic Fracture Mechanics," International Journal of Fracture, 50, R33-R38 (1991).

Unger, D.J., "Analytic Continuation of Stresses Across a Mode I Elastoplastic Interface," Engineering Fracture Mechanics, 36, 763-776 (1990).

Unger, D.J., "A Transition Model of Crack Tip Plasticity," International Journal of Fracture, 44, R27-R31 (1990).

Unger, D.J. and Aifantis, E.C., "Equilibrium of a Solute in an Elastic Continuum-A Statistical
Approach," Acta Mechanica, 81, 227-233 (1990).

Unger, D.J., "A Modified Stefan Problem for Transport-Controlled Stress Corrosion Cracking," Engineering Fracture Mechanics, 37, 101-106 (1990).

Unger, D.J., "A Finite-Width Dugdale Zone Model for Mode III," Engineering Fracture Mechanics, 34, 977-987 (1989).

Unger, D.J., "A Mathematical Analysis for Impending Hydrogen Assisted Crack Propagation,"
Engineering Fracture Mechanics, 34, 657-667 (1989).

Unger, D.J. and Aifantis, E.C., "Completeness of Solutions in the Double Porosity Theory," Acta Mechanica, 75, 269-274 (1988).

Lee, S.L. and Unger, D.J., "A Decohesion Model for Hydrogen Assisted Cracking," Engineering Fracture Mechanics, 31, 647-660 (1988).

Unger, D.J., "Moving Boundary Value Problems in Environmental Cracking Phenomena," Final report to the National Science Foundation for Grant MEA-8404065 (1987).

Unger, D.J., "A Closed Form Solution for the Limit Moment in the Plastic Torsion of an Elliptical Cylinder," Acta Mechanica, 67, 229-231 (1987)

Unger, D.J., "On a Decohesion Model of Hydrogen Assisted Cracking," Proceedings of the Tenth U.S. National Congress of Applied Mechanics, Austin (1986).

Unger, D.J., "Completeness of Solutions for Consolidation Problems with Double Porosity," Proceedings of the Tenth U.S. National Congress of Applied Mechanics, Austin (1986).

Unger, D.J., "The Exact Moment for the Plastic Torsion of a Cylinder of Elliptical Cross Section," Acta Mechanica, 61, 209-215 (1986).

Unger, D.J., "Steady-State Diffusion in Moving Frames of Reference," contributed paper, Developments in Mechanics, Vol. 13, Proceedings of the 19th Midwestern Mechanics Conference, The Ohio State University, 307-308 (1985).

Unger, D.J., "Elastic Torsion of a Hippopede," Mechanics Research Communications, 11, 207-209 (1984).

Unger, D.J., "Recent Results in the Modeling of Environmental Crack Phenomena," invited paper, Abstracts of the 21st Annual Meeting of the Society of Engineering Science, VPI, p. 54 (1984).

Unger, D.J. and Aifantis, E.C., "Dynamic Effects in Spinodal Decomposition," International Journal of Engineering Science, 22, 1219-1224 (1984).

Unger, D.J., "The Role of Diffusion in Environmental Cracking," invited paper, presented at the Mini-symposium, Microstructures and Inelasticity, Michigan Technological University (1984).

Chung, H., Unger, D.J., Macdonald, D.D., and Aifantis, E.C., "Steady and Non-Steady Crack Growth Under Environmental Conditions," paper 3-3, presented at Sixteenth ASTM National Symposium on Fracture Mechanics, Battelle, Columbus, OH (1983).

Unger, D.J., "Wave Propagation in Spinodally Decomposing Media," invited paper workshop - Media with Microstructure and Wave Propagation, Michigan Technological University (1983).

Unger, D.J., Gerberich, W.W., and Aifantis, E.C., "Further Remarks on an Exact Solution for Crack Problems," Engineering Fracture Mechanics, 18, 735-741 (1983).

Unger, D.J. and Aifantis, E.C., "On the Theory of Stress-Assisted Diffusion with Implications for Environmental Cracking Phenomena," Proceedings of the Ninth U.S. National Congress of Applied Mechanics, Cornell University, ASME, 489-490 (1982).

Unger, D.J., Gerberich, W.W., and Aifantis, E.C., "Further Remarks on the Implications of Steady-State Stress-Assisted Diffusion on Environmental Cracking," Scripta Metallurgica, 16, 1059-1064 (1982).

Unger, D.J. and Aifantis, E.C., "Coupled Stress-Concentration Spinodals," Environmental Degradation of Engineering Materials in Aggressive Environments, Proceedings of the Second International Conference on Environmental Degradation of Engineering Materials at Virginia Tech., ed. M.R. Louthan, Jr., R.P. McNitt, and R.D. Sisson, VPI Press, 585-591 (1981).

Unger, D.J. and Aifantis, E.C., "Flow in Stems of Plants," Proceedings of the Third Engineering Mechanics Specialty Conference, University of Texas, Austin, ASCE, 501-504 (1979).

Unger, D.J. and Aifantis, E.C., "Solution of Some Diffusion Equations Related to Stress-Corrosion Cracking," proceedings of the First Environmental Degradation of Engineering Materials Conference at Virginia Tech, ed. M.R. Louthan, Jr. And R.P. McNitt, VPI press, 131-139 (1977).