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Road pavements are made of several layers, between which a bond must be ensured that meets the requirements. The bond is achieved by interlocking and gluing the materials at the layer boundary. Insufficient gluing and interlocking of the materials results in inadequate bonding, which in turn causes premature deformation and structural damage. This reduces the service life of a road pavement and thus also causes considerable maintenance costs. Therefore, knowledge of the material behavior at the layer boundary is essential. In recent years, research work on analyzing the layer bond in road pavements has been mainly limited to mechanical test methods. Mechanical test methods can be used to assess the quality of the layer bond, but do not allow separate analysis and accurate quantification of gluing and interlock. To develop more sustainable and durable materials, there is growing interest in the quantitative recording and evaluation of the effect of gluing and interlocking. To solve the above-mentioned problem, this thesis presents a new approach to analyzing gluing and interlocking using imaging techniques. In contrast to mechanical testing methods, imaging methods such as asphalt petrology can be used to analyze the void structure at the layer boundary. With high-resolution computed tomography, it is possible to analyze the material structure as well as quantify and visualize the areas at the layer interface where the materials glue together. The influence of gluing and interlocking on the material behavior is shown using close-range photogrammetry. By showing the failure points and quantifying the gluing in measurable parameters, new fundamental insights for the further development and application of the materials are achieved. In this work, gluing at the layer interface is first investigated using the imaging method of high-resolution computed tomography. By adding a high-density tracer, the materials could be segmented separately from each other at the layer interface for the first time. Using a developed evaluation method of the CT images, gluing can be transferred and analyzed for the first time by quantitative measured values and the calculation of the degree of gluing in numerical values. For a detailed analysis of the effects of gluing and interlocking, a shear test carried out is recorded using the close-range photogrammetry method and evaluated using the digital image correlation (DIC) method. What is new is that the strain states and the material failure at the layer interface can thus be shown and provide conclusions for optimizing the materials. Based on the findings from the experimental investigations, a layer interface model is developed using the finite element method, allowing predictions of the layer interface behavior to be modeled regarding the distribution and degree of gluing. By simulating the layer interface using the surface-based cohesive behavior, predictions regarding the bond behavior can be made and possibilities for optimizing the materials and the application technique could be presented. Overall, this work provides new insights into the material behavior at the layer bond and offers new methods for evaluating and quantifying the layer bond as well as models for predicting the material behavior at the layer interface, which will enable the production of more stable and durable road pavements in the future.