Interlaminar Shear Performance of the Asphalt Pavement with Gravel Base Considering the Influence of Gravel Embedded Rate

An asphalt pavement with gravel base (AP-GB) is used to alleviate the occurrence of reflective cracks. However, its interlaminar stability is affected by the gravel base's looseness and interlaminar complex contact form. In this situation, a viscoelastic model-cohesive zone model-random aggregate model (VM-CZM-RAM) composite structure model of AP-GB is proposed to describe the interlaminar complex contact form through the finite-element method. Meanwhile, the influences of gravel embedded in AP-GB interlamination stability are considered. Then based on this model, the effects of vertical load, horizontal shear speed, and interlaminar asphalt spraying dosage on interlaminar stability are investigated systematically. Results show that the interlaminar shear strength is positively correlated with the vertical load and shear speed under the model with the optimal interlaminar gravel embedded rate (5%). The best shear strength is obtained when the interlaminar asphalt spraying dosage is 0.8 L/m(2). Finally, a no-demolding specimen and its shear test method were designed to verify the feasibility of the model. The conclusions of this paper can highly help the structural design and application of the AP-GB. (C) 2021 American Society of Civil Engineers.

Automated summary

A viscoelastic model-cohesive zone model-random aggregate model (VM-CZM-RAM) composite structure model is proposed to describe the interlaminar complex contact form of AP-GB asphalt pavement with gravel base. The influences of gravel embedded in AP-GB on interlamination stability are considered. The results show that the interlaminar shear strength is positively correlated with the vertical load and shear speed under the optimal interlaminar gravel embedded rate.