Granular soils usually serve as the filler material in geotechnical engineering. This study presents the development and application of a stress-fractional model for granular soils with different initial material states. To capture the plastic loading and flow behaviors, a subloading surface with the fractional stress gradient is used. The developed model contains twelve parameters which can be determined through triaxial tests. To validate the developed model, the well-documented test results of Firoozkuh No. 161 sand and crushed basalt are simulated and discussed. It is found that the stress-fractional model can reasonably simulate the undrained and drained behaviors of granular soils consolidated with different densities and mean effective pressures.

中文翻译：

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应用应力分数模型来捕捉粒状土壤的应力应变行为

粒状土通常用作岩土工程中的填充材料。本研究介绍了具有不同初始材料状态的粒状土壤的应力分数模型的开发和应用。为了捕捉塑性载荷和流动行为，使用了具有分数应力梯度的子载荷表面。开发的模型包含十二个可以通过三轴试验确定的参数。为了验证开发的模型，模拟和讨论了 Firoozkuh No. 161 砂和破碎玄武岩的有据可查的测试结果。结果表明，应力分数模型可以合理模拟不同密度和平均有效压力固结的粒状土的不排水和排水行为。