1. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a long NRT bar fracture test developed by Costin, in which a NRT sample was loaded to fracture by a direct tensile stress pulse. The displacement was measured by an optical method, Moiré fringes, and the dynamic stress-intensity factor was determined by the quasistatic fracture theory. Reproduced from American Science for Testing Materials, 1977. Figure Legend:

2. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a reflected tensile fracture test developed by Stroppe. A cracked sample was loaded to failure by a tensile stress pulse reflected from a compressive stress pulse at the free end of the sample. Reproduced from “Dynamic fracture of steel at short loading times, impact loading and dynamic behavior of materials.” Figure Legend:

3. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of WLCT fracture test developed by Klepaczko. A compact tension specimen is sandwiched in between the loading wedge and the transmission bar and loaded to failure by a compressive stress pulse. Crack initiation time is detected by the small strain gauge mounted near the crack tip and the stress-intensity factor is computed by quasistatic fracture mechanics theory. Reproduced from Klepaczko. Figure Legend:

4. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of one-bar/1PB fracture test Mode I fracture toughness measurement developed by Homma. A striker bar impacts the incident bar against the 1PB specimen, and generates a compressive stress pulse down the incident bar toward the specimen, which is loaded and fractured by inertial force. Crack initiation time can be detected by the strain gauge and fracture gauge. The dynamic stress-intensity factor can be determined by the FEA and theoretical formulas. Reproduced from Weisbrod and Rittel. Figure Legend:

5. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a one-bar impact test for Mode II fracture toughness measurement developed by Rittel. The cracked side of the sample is in contact with the incident bar, and the sample is loaded to failure in a shear mode. Reproduced from Rittel. Figure Legend:

6. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a one-bar/3PB fracture test for fracture toughness measurement developed by Mines and Ruiz. The uncracked side of the sample is in contact with the incident bar. Reproduced from Rubio. Figure Legend:

7. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a two-bar/3PB fracture test for fracture toughness measurement developed by Tanaka. A transmission tube acts as the support, and load and displacement are determined by the transmitted and reflected pulses, respectively, under stress- equilibrium conditions. Reproduced from Tanaka and Kagatsume. Figure Legend:

8. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a modified two-bar/3PB fracture test for fracture toughness measurement developed by Vecchio’s group at UCSD. Pulse-shaping and momentum-trapping techniques are adopted for achieving a tailored loading pulse. Figure Legend:

9. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Loading configuration of a three-bar/3PB fracture test developed by Yokoyama. Here one incident bar serves as an impactor and two transmission bars act as supports. The dynamic stress-intensity factor is computed by FEA using both incident and transmitted loads; the one-point strain measurement method was applied. Reproduced from Yokoyama and Kishida. Figure Legend:

10. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a two-bar/CCS fracture test for fracture toughness measurement developed by Rittel A compact compression sample is sandwiched between the incident and transmission bars, and crack initiation time is detected by a fracture gauge. Reproduced from Rittel. Figure Legend:

11. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Configuration of a two-bar/Brazilian disk fracture test for brittle materials. A Brazilian disk sample with a center notch is sandwiched between the incident and transmission bars and loaded to failure by a compressive pulse. The Mode I and Mixed Mode I/II fracture tests can be performed by changing the angle θ. Reproduced from Zhou. Figure Legend:

12. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 Crack-tip coordinate reference Figure Legend:

13. Date of download: 5/28/2016 Copyright © ASME. All rights reserved. From: Hopkinson Bar Loaded Fracture Experimental Technique: A Critical Review of Dynamic Fracture Toughness Tests Appl. Mech. Rev. 2009;62(6):060802-060802-39. doi:10.1115/1.3124647 The comparison of natural frequency ω1/ω0 determined by different models. Here the frequencies are normalized by the fundamental frequency of a simply supported uncracked beam, i.e., ω0=(π/S)2EI/ρA. The specimen dimensions are 10×10×55 mm3 with a/W=0.5, S/W=4, and it is assumed to be in a state of plane strain. Figure Legend: