Skip to main content
Log in

Measurement of Orthogonal Stress Gradients Due to Impact Load on a Transparent Sheet using Digital Gradient Sensing Method

  • Published:
Experimental Mechanics Aims and scope Submit manuscript

Abstract

A full-field optical method called Digital Gradient Sensing (DGS) for measuring stress gradients due to an impact load on a planar transparent sheet is presented. The technique is based on the elasto-optic effect exhibited by transparent solids due to an imposed stress field causing angular deflections of light rays quantified using 2D digital image correlation method. The measured angular deflections are proportional to the in-plane gradients of stresses under plane stress conditions. The method is relatively simple to implement and is capable of measuring stress gradients in two orthogonal directions simultaneously. The feasibility of this method to study material failure/damage is demonstrated on transparent planar sheets of PMMA subjected to both quasi-static and dynamic line load acting on an edge. In the latter case, ultra high-speed digital photography is used to perform time-resolved measurements. The quasi-static measurements are successfully compared with those based on the Flamant solution for a line-load acting on a half-space in regions where plane stress conditions prevail. The dynamic measurements, prior to material failure, are also successfully compared with finite element computations. The measured stress gradients near the impact point after damage initiation are also presented and failure behavior is discussed.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18

Similar content being viewed by others

Notes

  1. For simplicity, this approach was used instead of the solution to the Lamb problem [40]. Lamb solutions are available for a line pulse or a suddenly imposed constant line load on an elastic half-space; for large values of time, the latter case reduces to the elastostatic solution. The applied load history in this case being approximately a ramp transitioning to a constant value, elastostatic behavior is to be expected behind the shear wave front.

References

  1. Strassburger E (2009) Ballistic testing of transparent armour ceramics. J Eur Ceram Soc 29(2):267–273

    Article  Google Scholar 

  2. Patel P et al (2000) Transparent armor. AMPTIAC Newsletter, 4(3)

  3. Iwamoto S et al (2005) Optically transparent composites reinforced with plant fiber-based nanofibers. Appl Phys Mater Sci Process 81(6):CP8-1112

    Article  Google Scholar 

  4. Pope EJA, Asami M, Mackenzie JD (1989) Transparent silica gel-PMMA composites. J Mater Res 4(4):1018–1026

    Article  Google Scholar 

  5. Ravi S (1998) Development of transparent composite for photoelastic studies. Adv Compos Mater 7(1):73–81

    Article  Google Scholar 

  6. Yano H, Sugiyama J, Nakagaito AN et al (2005) Optically transparent composites reinforced with networks of bacterial nanofibers. Adv Mater 17(2):153–155

    Article  Google Scholar 

  7. de Graaf JGA (1964) Investigation of brittle fracture in steel by means of ultra high speed photography. Appl Opt 3(11):1223–1229

    Article  Google Scholar 

  8. Dally JW (1979) Dynamic photo-elastic studies of fracture. Exp Mech 19(10):349–361

    Article  Google Scholar 

  9. Parameswaran V, Shukla A (1998) Dynamic fracture of a functionally gradient material having discrete property variation. J Mater Sci 33(13):3303–3311

    Article  Google Scholar 

  10. Rosakis AJ, Kanamori H, Xia K (2006) Laboratory earthquakes. Int J Fract 138(1–4):211–218

    Article  MATH  Google Scholar 

  11. Beinert J, Kalthoff JF (1981) Mechanics of fracture. In: Sih GC (ed) Nijhoff Publishers, Vol. 7, pp. 281–328

  12. Zehnder AT, Rosakis AJ (1986) A note on the measurement of K and J under small-scale yielding conditions using the method of caustics. Int J Fract 30(3):R43–R48

    Article  Google Scholar 

  13. Krishnaswamy S, Rosakis AJ (1991) On the extent of dominance of asymptotic elastodynamic crack-tip fields: an experimental study using bifocal caustics. J Appl Mech—Trans ASME 58(1):87–94

    Article  Google Scholar 

  14. Tippur HV (1992) Coherent gradient sensing—A Fourier optics analysis and applications to fracture. Appl Opt 31(22):4428–4439

    Article  Google Scholar 

  15. Tippur HV, Krishnaswamy S, Rosakis AJ (1991) A coherent gradient sensor for crack tip measurements: analysis and experimental results. Int J Fract 48:193–204

    Article  Google Scholar 

  16. Kirugulige MS, Kitey R, Tippur HV (2004) Dynamic fracutre behavior of model sandwich structures with functionally graded core; a feasibility study. Compos Sci Tech 65:1052–1068

    Article  Google Scholar 

  17. Kirugulige MS, Tippur HV (2006) Mixed mode dynamic crack growth in functionally graded glass filled epoxy. Exp Mech 46:269–281

    Article  Google Scholar 

  18. Lee J, Kokaly MT, Kobayashi AS (1998) Dynamic ductile fracture of aluminum SEN specimens an experimental-numerical analysis. Int J Fract 93:39–50

    Article  Google Scholar 

  19. Chiang FP, Gupta PK (1989) Laser speckle interferometry applied to studying transient vibrations of a cantilever beam. J Sound Vibr 133(2):251–259

    Article  Google Scholar 

  20. Sanford RJ (2003) Principles of fracture mechanics. Prentice Hall

  21. Chu TC, Ranson WF, Sutton MA, Peters WH (1985) Applications of digital image correlation techniques to experimental mechanics. Exp Mech 25(3):232–244

    Article  Google Scholar 

  22. Chao YJ, Luo PF, Kalthoff JF (1998) An experimental study of the deformation fields around a propagating crack tip. Exp Mech 38(2):79–85

    Article  Google Scholar 

  23. Kirugulige MS, Tippur HV, Denney TS (2007) Measurement of transient deformations using digital image correlation method and high-speed photography: application to dynamic fracture. Appl Opt 46(22):5083–5096

    Article  Google Scholar 

  24. Kirugulige MS, Tippur HV (2009) Measurement of surface deformations and fracture parameters for a mixed-mode crack driven by stress waves using image correlation technique and high-speed photography. 45(2), 108–122

  25. Reu PL, Miller TJ (2008) The application of high-speed digital image correlation. J Strain Anal Eng Des 43(8):673–688

    Article  Google Scholar 

  26. Pankow M, Justusson B, Waas AM (2010) Three-dimensional digital image correlation technique using single high-speed camera for measuring large out-of-plane displacements at high framing rates. Appl Opt 49(17):3418–3427

    Article  Google Scholar 

  27. Sutton MA, Orteu U, Schreier H (2009) Image correlation for shape, motion and deformation measurements. Springer

  28. Lu H, Cary PD (2000) Deformation measurements by digital image correlation: implementation of a second-order displacement gradient. Exp Mech 40(4):393–400

    Article  Google Scholar 

  29. Periasamy C, Tippur HV (2012) A full-field digital gradient sensing method for evaluating stress gradients in transparent solids. Appl Opt

  30. Tippur HV, Krishnaswamy S, Rosakis AJ (1991) Optical mapping of crack tip deformations using the methods of transmission and reflection Coherent Gradient Sensing—A study of crack tip K-dominance. Int J Fract 52(2):91–117

    Google Scholar 

  31. Born M, Wolf E (1999) Principles of optics, 7th edn. Cambridge University Press

  32. Tippur HV (1994) Interpretation of fringes obtained with coherent gradient sensing. Appl Opt 33(19):4167–4170

    Article  Google Scholar 

  33. Budynas RG (1998) Advanced strength and applied stress analysis. McGraw-Hill

  34. Periasamy C, Jhaver R, Tippur HV (2010) Quasi-static and dynamic compression response of a lightweight interpenetrating phase composite foam. Mater Sci Eng A 527(12):2845–2856

    Article  Google Scholar 

  35. Butcher RJ, Rousseau CE, Tippur HV (1998) A functionally graded pariculate composite: preparation, measurements and failure analysis. Acta Mater 47(1):259–268

    Article  Google Scholar 

  36. Meyers M (1994) Dynamic behavior of materials. John Wiley & Sons, Inc., pp. 305–307

  37. Dally JW, Riley WF (2005) Experimental stress analysis, 4 edn. College House Enterprises

  38. Mohajerani A, Spelt JK (2011) Edge chipping of borosilicate glass by low velocity impact of spherical indenters. Mech Mater 43(11):671–683

    Article  Google Scholar 

  39. Chai H, Ravichandran G (2009) On the mechanics of fracure in monoliths and multilayers from low-velocity impact by sharp or blunt-tip projectiles. Int J Impact Eng 36(3):375–385

    Article  Google Scholar 

  40. Verruijt A (2008) An approximation of the Rayleigh stress waves generated in an elastic half plane. Soil Dynam Earthquake Eng 28:159–168

    Article  Google Scholar 

Download references

Acknowledgments

Partial support for this research through grants W911NF-12-1-0317 from the U.S. Army Research Office and NSF-CMMI-1232821 from the National Science Foundation is gratefully acknowledged.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to H. V. Tippur.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Periasamy, C., Tippur, H.V. Measurement of Orthogonal Stress Gradients Due to Impact Load on a Transparent Sheet using Digital Gradient Sensing Method. Exp Mech 53, 97–111 (2013). https://doi.org/10.1007/s11340-012-9653-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11340-012-9653-x

Keywords

Navigation