1 of 1

Characterization on the Mechanical Behavior of Gastrocnemius Using Analytical and Finite Element Analyses

11th Annual COE Graduate Poster Presentation Competition

Student: Shunafrica C. White¹ (PhD)

Advisor: Dr. Matthew B.A. McCullough²

​

• Department of Mechanical Engineering
• Department of Chemical, Biological, and Bioengineering/The Graduate College

Cross-Disciplinary Research Area: Biomechanics

MOTIVATION

OBJECTIVE

Experimental Testing

Constitutive Modeling

Statistical Analysis

Advanced glycation end products deviate the normal behavior of diabetic soft tissues and diminishes the tissue’s structure.

​

However, investigations (e.g., analytical and FEA, experimental and FEA, and FEA only) on the mechanics of diabetic soft tissues mainly focus on plantar soft tissues and have been well documented.

​

Thus, there is a need for shifted interest in diabetic soft tissues of the knee, and so the purpose of the study was to develop an approach for modeling the material behavior of gastrocnemius (i.e., calf muscle) that will be applied in a future investigation on the mechanical behavior of the diabetic patellar tendon.

Predict the mechanical behavior of a gastrocnemius test coupon by (1) applying a curve fit technique to optimize the material constants of the Yeoh constitutive model and (2) simulating a tensile test and comparing the simulated and experimental solutions.

METHODOLOGY (CONT.)

Curve Fit

Mean squared and percentage error, and “fval” determined the error between the predicted and experimental values and between the simulated and experimental values.

RESULTS

DISCUSSION/CONCLUSION

ACKNOWLEDGEMENTS

BIOFABB Lab Group and Title III HBGI PhD Fellowship

REFERENCES

• Shan et al., Morphological and mechanical properties of the human triceps surae aponeuroses taken from elderly cadavers: Implications for muscle-tendon interactions. PLos ONE 14(2), 2019.
• Fung, YC. Biomechanics Mechanical Properties of Living Tissues. Springer-Verlag, 1981.
• Holzapfel, Gerhard A. Nonlinear Solid Mechanics: a Continuum Approach for Engineering. Wiley, 2010.

Table 1. The material constants of the Yeoh model (left) and error between the predicted and experimental stress (right).

Figure 2. Curves of Cauchy stress vs. Stretch as predicted by the Yeoh model, simulated during FEA, and as recorded during experimental testing.

METHODOLOGY

Load-deformation data, acquired from uniaxial tensile test of a gastrocnemius test coupon, were obtained from the literature [1].

Data Processing

Finite Element Analysis

Simulated values that were considered include deformation, and engineering strain and stress. The simulated values were used to calculate stretch and Cauchy stress.

Figure 1. Simulated tensile test with loading/boundary conditions.

Table 2. Error between the simulated and experimental deformation, engineering strain, stretch, and Cauchy stress.