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Semi-rigid base asphalt pavement has been widely utilized and various interlayer distresses occur during its service life due to temperature, vehicle loads and water, which weaken the interlayer performance between the base and surface layers. This review primarily investigates the mechanisms of interlayer distress in semi-rigid base asphalt pavement, as well as the evaluation methods for interlayer performance and the methods for treating interlayer distress. Interlayer distress is caused by the weakening of interlayer performance, manifested specifically in inadequate interlayer bonding strength and cracking resistance. Accordingly, researchers have proposed various methods for evaluating interlayer performance, including shear tests, tensile tests, torsional tests, fatigue tests, and non-destructive testing methods. Measures for treating interlayer distress can be categorized into pavement materials and structural design, application of tack coats, and installation of interlayers. Among them, asphalt emulsion is the most commonly used tack coat material to enhance interlayer bonding performance significantly. Meanwhile, during the application of tack coats, mechanical parameters should be controlled strictly and ensure high construction quality. Interlayers installation was proven to delay and prevent crack propagation effectively, reducing crack-related distress significantly. The lower life cycle cost (LCC) of permanent semi-rigid base asphalt pavement makes it present high application potential. It is recommended to consider interlayer installation in semi-rigid base asphalt pavement design and take appropriate measures to enhance interlayer performance effectively. [Display omitted] • Inadequate interlayer performance can easily lead to deformation, cracks and other distresses. • Shear test is the easiest way to evaluate bonding properties but non-destructive test becomes popular. • It was found that application of tack coats can effectively minimize interlayer distresses. • Semi-rigid base asphalt pavements are a viable alternative to permanent pavements. [ABSTRACT FROM AUTHOR]

[Display omitted] • Optical fiber sensors have better corrosion, electromagnetic interference resistance and signal-to-noise ratio. • Optical fiber sensors can measure the strain, temperature and pressure information of pavement in real time. • The applications of optical fiber sensors in pavement are more and more extensive. Optical fiber sensor (OFS) is a commonly used tool to monitor the serviceability and integrity of pavements. The earliest application of optical fiber sensors in the road can be traced back to the early 21st century, and development of this technique has been extensively studied after that. In view of the increasing demand for pavement nondestructive testing and the rapid development of optical fiber sensor technology, this work summarizes the optical fiber sensors commonly used in road engineering and the classification methodologies. After that, the basic principle of fiber Bragg grating (FBG) sensor and the application of this sensor in the pavement were discussed. Finally, the principle and application of distributed optical fiber sensors (DOFS) in the pavement were included as well. Overall, this review found that FBG sensors can accurately measure and monitor road strain, temperature, pressure and WIM measurement by employing analytical-based methods. Distributed optical fiber sensors can measure pavement crack width, identify the void under the concrete slab, and obtain vehicle load (load size, load moving speed, axle type) and other data. Currently, it has been proved that the installation of the installation of fiber optic sensors on the road surface is an effective method to monitor the integrity of the road structure under traffic, but further tests in real traffic environment to further improve the survival rate of fiber optic sensors and evaluate the accuracy of the measured results are still needed. [ABSTRACT FROM AUTHOR]