Blood clots play a diametric role in our bodies as they are both vital as a wound sealant, as well as the source for many devastating diseases. In blood clots’ physiological and pathological roles, their mechanics play a critical part. These mechanics are non-trivial owing to blood clots’ complex nonlinear, viscoelastic behavior. Casting this behavior into mathematical form is a fundamental step toward a better basic scientific understanding of blood clots, as well as toward diagnostic and prognostic computational models. Here, we identify a hyper-viscoelastic damage model that we fit to original data on the nonlinear, viscoelastic behavior of blood clots. Our model combines the classic Ogden hyperelastic constitutive law, a finite viscoelastic model for large deformations, and a non-local, gradient-enhanced damage formulation. By fitting our model to cyclic tensile test data and extension-to-failure data, we inform the model’s nine unknown material parameters. We demonstrate the predictability of our model by validating it against unseen cyclic tensile test and stress-relaxation data. Our original data, model formulation, and the identified constitutive parameters of this model are openly available for others to use, which will aid in developing accurate, quantitative simulations of blood clot mechanics.

血凝块在我们的身体中起着至关重要的作用，因为它们既是伤口密封剂，也是许多破坏性疾病的根源。在血栓的生理和病理作用中，它们的机制起着至关重要的作用。由于血凝块具有复杂的非线性粘弹性行为，这些机制并非微不足道。将这种行为转化为数学形式是朝着更好地了解血栓的基础科学以及朝着诊断和预后计算模型迈出的基本一步。在这里，我们确定了一个超粘弹性损伤模型，我们将其拟合到关于血凝块的非线性粘弹性行为的原始数据。我们的模型结合了经典的 Ogden 超弹性本构定律、大变形的有限粘弹性模型和非局部梯度增强损伤公式。通过将我们的模型拟合到循环拉伸测试数据和延伸至失效数据，我们告知模型的九个未知材料参数。我们通过对看不见的循环拉伸试验和应力松弛数据进行验证，证明了我们模型的可预测性。我们的原始数据、模型公式和已确定的该模型的本构参数可供其他人使用，这将有助于开发准确、定量的血凝块力学模拟。