PURPOSES : This study evaluates the mechanical properties of high-viscosity polymer-modified asphalt binders using PG and MSCR tests. METHODS : Using the Superpave asphalt binder performance grade (PG) and multi-stress creep recovery (MSCR) test methods, the linear (dynamic shear modulus, stiffness, and viscosity) and non-linear properties — i.e., non-recoverable compliance (Jnr) and recoverable shear strain % recovery — of 16 different types (SBS, SIS, PE, PP) of polymer-modified asphalt binders were assessed. RESULTS : Based on the viscosity testing results. Most PG 82 binders did not meet the criterion of 3 Pa ·s. This indicates that they need to increase the mixing and compaction temperatures to reduce the high viscosity. The MSCR % Jnr results demonstrated that PG 76, PG 82–22, and PG 82-28/34 binders were below 1.0, 0.5, and 0.2, respectively. In addition, the MSCR % recovery results showed that PG 76, PG82-22, and PG82-28/34 were above 35 %, 55 %, and 80 %, respectively. CONCLUSIONS : It was found that the % Jnr decreased with an increase in the high-temperature PG of the asphalt binder, whereas the % recovery increased as the low-temperature PG of the binder increased.

PURPOSES : This study uses deep learning image classification models and vehicle-mounted cameras to detect types of pavement distress — such as potholes, spalling, punch-outs, and patching damage — which require urgent maintenance. METHODS : For the automatic detection of pavement distress, the optimal mount location on a vehicle for a regular action camera was first determined. Using the orthogonal projection of obliquely captured surface images, morphological operations, and multi-blob image processing, candidate distressed pavement images were extracted from road surface images of a 16,036 km in-lane distance. Next, the distressed pavement images classified by experts were trained and tested for evaluation by three deep learning convolutional neural network (CNN) models: GoogLeNet, AlexNet, and VGGNet. The CNN models were image classification tools used to identify and extract the combined features of the target images via deep layers. Here, a data augmentation technique was applied to produce big distress data for training. Third, the dimensions of the detected distressed pavement patches were computed to estimate the quantity of repair materials needed. RESULTS : It was found that installing cameras 1.8 m above the ground on the exterior rear of the vehicle could provide clear pavement surface images with a resolution of 1 cm per pixel. The sensitivity analysis results of the trained GoogLeNet, AlexNet, and VGGNet models were 93 %, 86 %, and 72 %, respectively, compared to 62.7 % for the dimensional computation. Following readjustment of the image categories in the GoogLeNet model, distress detection sensitivity increased to 94.6 %. CONCLUSIONS : These findings support urgent maintenance by sending the detected distressed pavement images with the dimensions of the distressed patches and GPS coordinates to local maintenance offices in real-time.

PURPOSES: In order to apply high-speed weigh-in-motion (HS WIM) systems to asphalt pavement, three high-durability asphalt concrete mixtures installed with a WIM epoxy are evaluated. METHODS: In this study, dynamic stability, number of loading repetitions to reach the rut depth of 1 mm, and rut depth measurements of three asphalt mixtures at 60℃ were compared using an Asphalt Pavement Analyzer (APA). Laboratory-fabricated material and field core samples were prepared and tested according to KS F2374. RESULTS : Through the laboratory tests, it was found that all three modified asphalt mixtures (stone-mastic, porous, and semi-rigid) with WIM epoxy showed favorable permanent deformation results and passed the dynamic stability criterion of 3000 loading repetitions per 1 mm. In addition, it was confirmed that the modified SMA mixtures cored from the field construction yields satisfactory rutting testing results using the APA. Finally, the epoxy used for the HS WIM installation shows good adhesion with the three asphalt mixtures and permanent deformation resistance.

The cultivation methods of Acanthopanax in Korea need to be optimized. Hence, this study investigated the effect of different fertilizer ratios and planting dates on the growth and acanthoside D content of two (2) Acanthopanax species. The current recommended fertilizer rate of 10.5-8.5-8.5 kg/ha- (N-P2O5-K2O, respectively) produced the best plant growth of Acanthopanax. For the first year, the acanthoside D content resulting from the 2P (2x phosphate) rate was higher than that from the other fertilizer ratios, yet there were no significant differences resulting from the various treatments for either Acanthopanax divaricatus or Acanthopanax koreanum. Similarly, for the second year, there were no significant differences in the acanthoside D content resulting from the various fertilizer ratios, although for both species the acanthoside D content resulting from the 2P rate was slightly higher than that from the other treatments. Therefore, the results indicated that doubling the amount of phosphate increased the acanthoside D content. Plus, the optimum planting date with respect to growth and productivity for Acanthopanax divaricatus was identified as April 15. The cultivation methods of Acanthopanax in Korea need to be optimized. Hence, this study investigated the effect of different fertilizer ratios and planting dates on the growth and acanthoside D content of two (2) Acanthopanax species. The current recommended fertilizer rate of 10.5-8.5-8.5 kg/ha- (N-P2O5-K2O, respectively) produced the best plant growth of Acanthopanax. For the first year, the acanthoside D content resulting from the 2P (2x phosphate) rate was higher than that from the other fertilizer ratios, yet there were no significant differences resulting from the various treatments for either Acanthopanax divaricatus or Acanthopanax koreanum. Similarly, for the second year, there were no significant differences in the acanthoside D content resulting from the various fertilizer ratios, although for both species the acanthoside D content resulting from the 2P rate was slightly higher than that from the other treatments. Therefore, the results indicated that doubling the amount of phosphate increased the acanthoside D content. Plus, the optimum planting date with respect to growth and productivity for Acanthopanax divaricatus was identified as April 15. The cultivation methods of Acanthopanax in Korea need to be optimized. Hence, this study investigated the effect of different fertilizer ratios and planting dates on the growth and acanthoside D content of two (2) Acanthopanax species. The current recommended fertilizer rate of 10.5-8.5-8.5 kg/ha- (N-P2O5-K2O, respectively) produced the best plant growth of Acanthopanax. For the first year, the acanthoside D content resulting from the 2P (2x phosphate) rate was higher than that from the other fertilizer ratios, yet there were no significant differences resulting from the various treatments for either Acanthopanax divaricatus or Acanthopanax koreanum. Similarly, for the second year, there were no significant differences in the acanthoside D content resulting from the various fertilizer ratios, although for both species the acanthoside D content resulting from the 2P rate was slightly higher than that from the other treatments. Therefore, the results indicated that doubling the amount of phosphate increased the acanthoside D content. Plus, the optimum planting date with respect to growth and productivity for Acanthopanax divaricatus was identified as April 15. The cultivation methods of Acanthopanax in Korea need to be optimized. Hence, this study investigated the effect of different fertilizer ratios and planting dates on the growth and acanthoside D content of two (2) Acanthopanax species. The current recommended fertilizer rate of 10.5-8.5-8.5 kg/ha- (N-P2O5-K2O, respectively) produced the best plant growth of Acanthopanax. For the first year, the acanthoside D content resulting from the 2P (2x phosphate) rate was higher than that from the other fertilizer ratios, yet there were no significant differences resulting from the various treatments for either Acanthopanax divaricatus or Acanthopanax koreanum. Similarly, for the second year, there were no significant differences in the acanthoside D content resulting from the various fertilizer ratios, although for both species the acanthoside D content resulting from the 2P rate was slightly higher than that from the other treatments. Therefore, the results indicated that doubling the amount of phosphate increased the acanthoside D content. Plus, the optimum planting date with respect to growth and productivity for Acanthopanax divaricatus was identified as April 15. The cultivation methods of Acanthopanax in Korea need to be optimized. Hence, this study investigated the effect of different fertilizer ratios and planting dates on the growth and acanthoside D content of two (2) Acanthopanax species. The current recommended fertilizer rate of 10.5-8.5-8.5 kg/ha- (N-P2O5-K2O, respectively) produced the best plant growth of Acanthopanax. For the first year, the acanthoside D content resulting from the 2P (2x phosphate) rate was higher than that from the other fertilizer ratios, yet there were no significant differences resulting from the various treatments for either Acanthopanax divaricatus or Acanthopanax koreanum. Similarly, for the second year, there were no significant differences in the acanthoside D content resulting from the various fertilizer ratios, although for both species the acanthoside D content resulting from the 2P rate was slightly higher than that from the other treatments. Therefore, the results indicated that doubling the amount of phosphate increased the acanthoside D content. Plus, the optimum planting date with respect to growth and productivity for Acanthopanax divaricatus was identified as April 15.