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Asphalt mixture rutting may involve vertical compaction, volumetric dilation, and shear-induced lateral movement, depending on many factors. Both in the field and in the laboratory [e.g., Hamburg wheel tracker (HWT) and asphalt pavement analyzer (APA) tests], lateral movement of a mixture creates a heave region and a vertical permanent deformation along the wheel path. Typical laboratory wheel tracking tests such as HWT and APA measure the depth of pure vertical permanent deformation; field measurements measure rut depth and heave height. Currently, HWT and APA test devices are not equipped to measure heave height. The objective of this study was to develop an image-based heave height measurement methodology for HWT-tested asphalt specimens. The method can easily be extended to other wheel tracking tests, such as the APA. The study also included the generation of a three-dimensional (3D) model of HWT-tested asphalt specimens, the extraction of 3D coordinates, and the calculation of specimen heave height and rut depth. The proposed methodology was verified by comparing the calculated rut depths with laboratory-measured rut depths. The proposed methodology measured the heave height of the HWT-tested specimens with reasonable accuracy. Furthermore, a linear relationship was observed between the rut depth and heave height of the tested specimens. This research will help researchers evaluate asphalt mixture heave resistance and will extend state-of-the-art research in the domain. [ABSTRACT FROM AUTHOR]

Embedded infiltration rings have been historically used to estimate the infiltration properties of pervious concrete (PC) pavements. However, no methodical study has evaluated the effect of the size of embedded rings on the infiltration characteristics of these special pavement systems. The objective of this research was to assess the infiltration rate of PC using a multi-scale, in situ approach through embedding rings of various sizes in pavement slabs. Essentially, this investigation attempted to identify the most appropriate size of the embedded ring that can estimate infiltration rates of PC slabs in a reliable manner. To meet the proposed objective, a multi-scale in situ experimental program was designed, in which five infiltration rings of inner diameter ranging from 100 to 580 mm were embedded into three PC slabs of dimensions 3 × 2.5 × 0.15 m. A surface infiltration test was also conducted on PC slabs and was found to vary from 0.36 to 1.87 cm/s. The embedded infiltration rate (EIR) was estimated using a falling head permeability test by ponding water above the pavement surface and measuring the time taken to drain. EIRs decreased from 1.36 to 0.27 cm/s with increasing ring diameter from 100 to 580 mm. Field tests also indicated that infiltration rates for smaller ring diameters (180 mm and lower) had higher uncertainty, which was attributed to the inability of achieving optimum compaction efforts inside of smaller rings. Based on the findings, the optimum size for estimating the infiltration rate of PC was found to be 270 mm. It is noteworthy that this diameter is in the range suggested by ASTM C1701, Standard Test Method for Infiltration Rate of In Place Pervious Concrete, i.e., 300 mm. This research helped identify the practicable specimen size that could be utilized by researchers and practitioners to estimate the most reliable field infiltration rates through PC. [ABSTRACT FROM AUTHOR]