Abstract:

In order to study the dynamic deformation characteristics of rubber-clay mixtures, resonance column tests were conducted on mixtures with different rubber contents, rubber particle sizes, and confining pressures. The development patterns of dynamic shear modulus G and damping ratio λ were analyzed. A calculation method for skeleton void ratio e_sk expressing the contact state of mixtures was proposed based on the binary medium model. Furthermore, the maximum dynamic shear modulus G_max of mixtures was evaluated based on skeleton void ratio e_sk. The results show that adding rubber particles leads to a decrease in G and increase in λ. As the rubber content increases, G decreases and λ increases. Additionally, G increases and λ decreases with increasing confining pressure. Moreover, G increases and λ decreases with increasing rubber particle diameter. With an increase in rubber content, the skeleton void ratio e_sk increases and G_max decreases. At the same rubber dosage, as the rubber particle size increases, e_sk increases and G_max rises. Based on Hardin’s formula, a characterization model of G_max considering rubber content and rubber particle size is proposed using skeleton void ratio e_sk. The model exhibits good accuracy and can serve as a basis for evaluating G_max of rubber-clay mixtures.

Key words: rubber-clay mixtures, dynamic shear modulus, damping ratio, skeleton void ratio, Hardin model