As the main organic component of shale, the kerogen has a direct impact on the shale reservoirs. A molecular aggregate is used to study mechanical behaviour of kerogen, of which the molecular weight distribution is rational conforming to the Gaussian distribution. The mechanical response of kerogen is obtained with different strain rates by using molecular dynamics simulations. The results show that kerogen shows material hardening and fracture strain decrease with the strain rate. In the plastic range, we analyse the causes of stress oscillation at the microscopic level, and obtain the relationship between the stress oscillation and hydrogen bond. A compressible hyper-viscoelastic constitutive model of kerogen is established, which describes the mechanical behaviour of kerogen with different strain rates. Our research provides a valuable insight in the kerogen properties, and helps to understand the mechanical behaviour of shale reservoirs from a micro-perspective.

作为页岩的主要有机成分，干酪根对页岩储层有直接影响。分子聚集体用于研究干酪根的力学行为，其分子量分布合理地符合高斯分布。通过使用分子动力学模拟，可以在不同的应变速率下获得干酪根的机械响应。结果表明，干酪根显示出材料硬化，并且断裂应变随应变速率而降低。在塑性范围内，我们在微观水平上分析了应力振荡的原因，并获得了应力振荡与氢键之间的关系。建立了干酪根的可压缩超粘弹性本构模型，该模型描述了不同应变速率下干酪根的力学行为。