Experimental Observation of High Strain Rate Responses of Porcine Brain, Liver, and Tendon

Clemmer, John S.; Prabhu, Raj; Chen, Joseph; Colebeck, E.; Priddy, Lauren B.; Mccollum, Michael; Brazile, Bryn; Whittington, Wilbur; Wardlaw, Jennifer L.; Rhee, Hongjoo; Horstemeyer, M.F.; Williams, Lakiesha N.; Liao, Jun

doi:10.1142/s0219519416500329

Cited by 7 publications

(12 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This study indicates that damage patterns under high tensile strains exhibited the most pronounced lacerations, which complements reports that describe tensile stress as the main contributor to liver lacerations frequently observed in traumatic abdominal injuries [49]. The damage evolution under compression loads is different so that it endures compression loads much better than tension and shear.…”

Section: Discussionsupporting

confidence: 86%

“…In all of these samples, the capsule was removed and testing was done solely on the liver parenchyma. Furthermore, directionality was not considered in our extracted samples, because liver tissue has been shown to exhibit an isotropic mechanical response to mechanical testing [32,49,50]. Control histology samples (n ¼ 2 per liver) were taken in a similar fashion using the shear sample stamp and used as a global control for all tests.…”

Section: Sample Preparation and Experiments Designmentioning

confidence: 99%

See 1 more Smart Citation

Quantitative Analysis of Tissue Damage Evolution in Porcine Liver With Interrupted Mechanical Testing Under Tension, Compression, and Shear

Chen

Brazile

Prabhu

et al. 2018

Journal of Biomechanical Engineering

Self Cite

View full text Add to dashboard Cite

In this study, the damage evolution of liver tissue was quantified at the microstructural level under tensile, compression, and shear loading conditions using an interrupted mechanical testing method. To capture the internal microstructural changes in response to global deformation, the tissue samples were loaded to different strain levels and chemically fixed to permanently preserve the deformed tissue geometry. Tissue microstructural alterations were analyzed to quantify the accumulated damages, with damage-related parameters such as number density, area fraction, mean area, and mean nearest neighbor distance (NND). All three loading states showed a unique pattern of damage evolution, in which the damages were found to increase in number and size, but decrease in NND as strain level increased. To validate the observed damage features as true tissue microstructural damages, more samples were loaded to the above-mentioned strain levels and then unloaded back to their reference state, followed by fixation. The most major damage-relevant features at higher strain levels remained after the release of the external loading, indicating the occurrence of permanent inelastic deformation. This study provides a foundation for future structure-based constitutive material modeling that can capture and predict the stress-state dependent damage evolution in liver tissue.

show abstract

Section: Discussionsupporting

confidence: 86%

Section: Sample Preparation and Experiments Designmentioning

confidence: 99%

Quantitative Analysis of Tissue Damage Evolution in Porcine Liver With Interrupted Mechanical Testing Under Tension, Compression, and Shear

Chen

Brazile

Prabhu

et al. 2018

Journal of Biomechanical Engineering

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is interesting to note that high strain rate testing of different tissues results in different degrees of initial stiffening. The results obtained by Prabhu et al for brain tissue and by Clemmer et al for liver tissue at high rate compression demonstrated a higher initial hardening peak when compared to liver data reported in this study [23,24]. The above observation leads to a hypothesis correlating the initial stiffening with concentration of cellular content/water content [23].…”

Section: Discussionsupporting

confidence: 70%

“…High strain rate testing was performed as per previously established protocol [23,24,25]. The PSHPB, made of commercially extruded natural polycarbonate (PC 1000) rods, was composed of a striker bar, an incident bar, and a transmitted bar with lengths of 0.762, 2.438, and 1.219 m, respectively, and a diameter of 38.1 mm (Figure 2a).…”

Section: Methodsmentioning

confidence: 99%

Mechanical Response of Porcine Liver Tissue under High Strain Rate Compression

et al. 2019

Self Cite

View full text Add to dashboard Cite

In automobile accidents, abdominal injuries are often life-threatening yet not apparent at the time of initial injury. The liver is the most commonly injured abdominal organ from this type of trauma. In contrast to current safety tests involving crash dummies, a more detailed, efficient approach to predict the risk of human injuries is computational modelling and simulations. Further, the development of accurate computational human models requires knowledge of the mechanical properties of tissues in various stress states, especially in high-impact scenarios. In this study, a polymeric split-Hopkinson pressure bar (PSHPB) was utilized to apply various high strain rates to porcine liver tissue to investigate its material behavior during high strain rate compression. Liver tissues were subjected to high strain rate impacts at 350, 550, 1000, and 1550 s−1. Tissue directional dependency was also explored by PSHPB testing along three orthogonal directions of liver at a strain rate of 350 s−1. Histology of samples from each of the three directions was performed to examine the structural properties of porcine liver. Porcine liver tissue showed an inelastic and strain rate-sensitive response at high strain rates. The liver tissue was found lacking directional dependency, which could be explained by the isotropic microstructure observed after staining and imaging. Furthermore, finite element analysis (FEA) of the PSHPB tests revealed the stress profile inside liver tissue and served as a validation of PSHPB methodology. The present findings can assist in the development of more accurate computational models of liver tissue at high-rate impact conditions allowing for understanding of subfailure and failure mechanisms.

show abstract

“…However, in a recent study on the dynamic response of the brain, part of the inertial effects was shown to be intrinsic to the material and that non-uniform stress-states were realized in the material [29]. As a major component of the brain, water proved crucial in instigating the initial hardening [29,30]. To date, no researcher has analyzed the effect of the amount of water within the brain that has undergone high impact loads.…”

Section: Introductionmentioning

confidence: 99%

Compressive Mechanical Properties of Porcine Brain: Experimentation and Modeling of the Tissue Hydration Effects

et al. 2019

Self Cite

View full text Add to dashboard Cite

Designing protective systems for the human head—and, hence, the brain—requires understanding the brain’s microstructural response to mechanical insults. We present the behavior of wet and dry porcine brain undergoing quasi-static and high strain rate mechanical deformations to unravel the effect of hydration on the brain’s biomechanics. Here, native ‘wet’ brain samples contained ~80% (mass/mass) water content and ‘dry’ brain samples contained ~0% (mass/mass) water content. First, the wet brain incurred a large initial peak stress that was not exhibited by the dry brain. Second, stress levels for the dry brain were greater than the wet brain. Third, the dry brain stress–strain behavior was characteristic of ductile materials with a yield point and work hardening; however, the wet brain showed a typical concave inflection that is often manifested by polymers. Finally, finite element analysis (FEA) of the brain’s high strain rate response for samples with various proportions of water and dry brain showed that water played a major role in the initial hardening trend. Therefore, hydration level plays a key role in brain tissue micromechanics, and the incorporation of this hydration effect on the brain’s mechanical response in simulated injury scenarios or virtual human-centric protective headgear design is essential.

show abstract

Experimental Observation of High Strain Rate Responses of Porcine Brain, Liver, and Tendon

Cited by 7 publications

References 24 publications

Quantitative Analysis of Tissue Damage Evolution in Porcine Liver With Interrupted Mechanical Testing Under Tension, Compression, and Shear

Quantitative Analysis of Tissue Damage Evolution in Porcine Liver With Interrupted Mechanical Testing Under Tension, Compression, and Shear

Mechanical Response of Porcine Liver Tissue under High Strain Rate Compression

Compressive Mechanical Properties of Porcine Brain: Experimentation and Modeling of the Tissue Hydration Effects

Contact Info

Product

Resources

About