Concrete waste is mainly used as recycled base course material for pavement, but in the future, a wide range of applications other than recycled base course material will be required. In this study, 100% recycled stabilized base course material and 100% recycled concrete were applied to pavement as pavement materials composed only of recycled materials. The evaluation items were strength properties, CO₂ emission reduction effect, and environmental safety. As a result, it was confirmed that 100% recycled stabilized base course material and 100% recycled concrete satisfied the strength as pavement materials, had the effect of reducing CO₂ emissions, and had environmental safety.

 The infrared spectroscopic analysis has been effective method for examining the deterioration of asphalt and the content of modifiers. Particularly, if the asphalt mixture can be analyzed directory by infrared spectroscopy, it will be a wider and useful of application. However, the analysis of the asphalt mixture is difficult because it is inhibited by fillers and aggregates of mixtures. This study examined the effects of mixed limestone powder and aggregates in asphalt samples, and pretreatment method to remove inhibitors in asphalt samples. As a result, the thresh hold content of fillers and aggregates included in the asphalt samples has been found for infrared spectroscopic analysis of the asphalt. In addition, the inhibitor can be eliminated by simple particle holding filters.

 In recent years, there has been an urgent need to develop a technology for the sustainable recycling of asphalt pavement waste materials, and various studies have been conducted. The authors have focused on the solvent and decomposition performance of high-temperature, high-pressure water for organic matter, and have developed a technology for restoring the properties of degraded asphalt by hydrothermal decomposition using high-temperature, high-pressure water at 350°C. In this study, the authors confirmed the adaptability of the hydrothermal decomposition method to degraded asphalt, and confirmed that the method can be applied to both degradation and regeneration of degraded asphalt. In this study, the adaptability of the hydrothermal decomposition method to degraded asphalt that has undergone multiple cycles of degradation and regeneration was confirmed. As a result, it was found that asphalt recovered by hydrothermal decomposition showed a greater recovery in elongation and a decrease in polymer content compared to the conventional regeneration method. It was also found that asphalt mixture blended with hydrothermally degraded asphalt satisfied the quality target values of the regenerated heated asphalt mixture based on the cracking coefficient.

 In order to extend the service life of asphalt pavements, it is important to prevent permanent deformation of the base course and subgrade and to prevent water retention. In general, prime coat is applied to stabilize the base course surface and prevent water from penetrating into the base course to keep the base course healthy. However, there is no laboratory test method to quantitatively evaluate the various base course protection effects of prime coat. Therefore, a laboratory performance evaluation method was developed to evaluate the performance of prime coat, which contributes to the long lasting pavements by suppressing permanent deformation of the base course and improving durability when rainwater retention occurs. Through this study, it was found that the asphalt emulsion performance required for long-term protection of base course are penetration, water resistance, and use of low penetration index bitumen.

 In recent years, waste plastic issues have become a big social problem, and its application to asphalt pavements has been attracting attention as an effective utilization method. In this study we focused on waste PET, which is one of the major waste plastics while its application to pavements has been limited due to its extremely high melting point and low asphalt compatibility. As a result, a polyester-based modifier with low melting temperature and good asphalt compatibility was developed by chemically reacting waste PET with specific alcohols and carboxylic acids. The asphalt mixture with this modifier showed significant improvements in rutting resistance and water/oil resistance, suggesting that it can provide superior pavement durability compared with conventional methods of applying waste PET.

 Silica sand and natural sand (high-quality sand) are used as bedding sand and joint sand for ILblock pavements. Since natural sand is expensive, it is thought that using an alternative material with the same performance as natural sand can contribute to cost reduction. Therefore, the authors focused on molten slag produced by incinerating household waste as an alternative to natural sand. Based on the understanding of the material properties by laboratory tests and the results of field tests conducted in actual construction, the applicability of the molten slag was examined.

 As a result, it was found that the molten slag had greater resistance to fine-graining and interlocking effect and that there was no significant difference in the results of the three-year field test, indicating that the molten slag used for bedding sand and joint sand had the same performance as the existing material.

 In Japan, the use of recycled asphalt aggregates in asphalt mixtures has been in earnest since the 1980s, and the use of recycled asphalt aggregates in modified asphalt mixtures has also been studied and applied. However, the fact is that the long-term performance of recycled and modified asphalt mixtures in cold, snowy regions has not been verified. In this study, we conducted a follow-up survey on the crack rate, etc. from the time of pavement to 20 years after the pavement was installed on the test construction of the recycled modified asphalt mixture on the national highway in 2001. In addition, cores were collected and the direction of crack generation was investigated. As a result, it was clarified that the higher the recycled mixture ratio, the more likely it is to cause wear in winter and cracks from the road surface.

 The demand for recycled asphalt mixture is increasing year by year, and there is concern that the quality of recycled asphalt concrete aggregate will deteriorate accordingly. Therefore, various studies on the recycling of asphalt pavement have being conducted. The authors have conducted laboratory tests to evaluate the properties of recycled asphalt mixtures that have been repeatedly recycled in laboratyory and recycled asphalt mixtures that were used the recycled aggregate in asphalt mixing plant. As a result, authors obtained the knowledge on the effects of the difference in the components of the rejuvenator, recycled aggregate ratio, and the degree of needle penetration of the bitumen on the crack resistance of the recycled asphalt mixture. In this study, a full-scale test section was constructed, and a accelerated loading test using a heavy vehicle was conducted to verify crack resistance. As a result, the same result as the laboratory test was obtained.

 Asphalt concrete is deteriorated by oxidation, UV rays, and others in service. It is necessary to conduct the fatigue test using core samples taken from sites in order to assess the fatigue damage state of the asphalt concrete. This study validated the relationship between the viscoelastic parameters and the number of cycles to fatigue failure by conducting the repeated compressive-tensile test using core cut samples and laboratory-aged specimens. As a result, it was observed that the fatigue damage accumulation status of asphalt mixture is related to the change in phase angle in the repeated loading process. And, it was clarified that the ease of accumulation of fatigue damage can be assessed by introducing unit phase angle variation as viscoelastic parameters.

 In recent years, the effect of water on deterioration of asphalt pavement has been revealed by several noteworthy researches conducted at airports and expressways and national roads in Japan. To further extend the service life of asphalt pavements, it is important to correctly understand the process of deterioration in consequence of the existance of water. Thus, reproduction of the damage observed in actual pavements as well as evaluation method to significantly compare and distinguish asphalt mixtures with different levels of moisture-resistance properties are considered mandetory. In this research, based on the mechanism revealed in previous studies behind stripping of asphalt mixture, a new method, which is a fusion of several current domestic and overseas methods, is proposed to evaluate moisture resistance of polymer modified asphalt mixture.

 Longitudinal and transverses cracks were found on pre stressed concrete pavement (here by PCP) in a road tunnel. According to inspection on site, the pc bars and strands which were installed in PCP were ruptured near large cracks and some cavities between PCP and subbase were confirmed around largely defected sections.

 So, the analytical study using by 3 dimensional non liner finite element analysis were carried out to clarify which factor give the worse effective to deflections. The size of cavity gave the worse influence to deflections rather than loss of pre stress before the occurrence of the flexural cracking from this analysis. And the load carrying behavior was changed to that of a beam type, when cavities at the bottom side occurred. Furthermore, the negative bending moment appeared on surface of PCP.

 Concrete pavement is more resistant to rutting and cracking than asphalt pavement, and it is expected to have a longer service life. However, it is known that damage will occur early in cold regions if frost heave countermeasures are not taken reliably. In this study, the applicability of a heat insulation method using XPS (extruded polystyrene foam insulation) was examined by test construction as a countermeasure against frost heaving when replacing existing asphalt pavement with concrete pavement. The pavement structure necessary for protecting the insulation and ensuring the quality of the roadbed was examined, the proof stress of the insulation was verified, and the insulation effect was analyzed by heat conduction analysis. Based on this result, the pavement cross section was determined and test construction was carried out. As a result, appropriate bearing capacity and expected heat insulation effect were obtained.

 In this study, to evaluate the influence of variability of the design variable on calculated strain for asphalt pavement, Monte Carlo simulation was demonstrated. The results are summarized as follows. (1) The design parameters having the greatest influence on the horizontal strain variability at the bottom of the asphalt layer are asphalt elastic modulus, base elastic modulus and asphalt thickness. (2) The design parameters having the greatest influence on the vertical strain variability at the top of the subgrade are layer thickness, subgrade elastic modulus and subgrade Poisson’s ratio. (3) In the case of thick asphalt layer, it was confirmed that the coefficient of variation of the strain became the constant value without depending on pavement structure and elastic modulus if coefficient of variation of each design variable was given. (4) On the other hand, when thickness of asphalt layer was thin, coefficient of variation of the strain greatly changed depending on pavement structure and elastic modulus.

 Multi-layered precast concrete pavement (MPCP) is a unique pavement structure consisting of a double-layer of RC slabs that are connected with a special pin. Since the concrete slabs is not connected with dowels, the slab is easily replaced. There have been no studies on the mechanical behaviors of two-layer structures such as MPCP. In this study, to establish the structural design method, values of structural parameters of MPCP were obtained from FWD test conducted on a MPCP. Also, another MPCP was subjected to moving heavy wheel loads and its behavior was observed. It was found that a gap between two slabs should be taken care of.

 In Japan, the pandemic of COVID-19 has increased the demand for bicycles in urban transportation, and the types of vehicles on the road are diverse. To develop a general-purpose bicycle vibration model and construct an evaluation index, this study conducted bicycle vibration tests and bicycle experience evaluation tests using various types of bicycles. As a result, the vibration characteristics of various bicycle models were identified, a general-purpose bicycle vibration model was developed, and the ap-plicability of the road surface evaluation index calculated based on the developed model to actual road surfaces was verified. It was found that the constructed indices had a high correlation with the ride quality evaluation of various bicycle models and could reflect the ride quality of bicycles even when they were driven on the road surface with various types of bicycles.

 Electric standing scooters are micro-mobility, which is a two-wheeled vehicle that has been rapidly spreading around the world in recent years, and compared to existing mobility, the tire diameter is about 10 inches, which is smaller and is more likely to be affected by paved roads. In this research, about driving experiments on electric standing scooter, we measured the road surface properties and analyzed the relationship between the vibration acceleration and the road surface properties from the viewpoint of the interaction between the vehicle and the road surface. The results showed that the vibration region specific to electric standing scooters is sensitive to mega-textures that are shorter than the roughness wavelength. From this, it was found that a new index that replaces IRI is necessary when performing road surface evaluation for electric standing scooters.

 In recent years, localized surface roughness on expressway road surfaces which occurs below current maintenance standards have become a factor that reduces the comfort of driving vehicles. The study focuses on the human-centered evaluation of road surfaces by conducting driving tests using a driving simulator. The driving test introduced two measures of physiological indices, the electrocardiogram (ECG) and the electrodermal activity (EDA), to comprehend unconscious mental stress of participants toword vehicle vibrations induced by the surface roughness. The results suggest that a localized decrease in flatness affects stress sensitivity. Moreover, the wavelength response of the road surface that causes stress is the cause of the discrepancy between the comfort of users and the maintenance criteria.

 Foot strike impact during running is an important issue for long distance runners because it largely affects their fatigue and injury. It is easy to assume that the impact depends on hardness of pavement surface as well as runner's weight, their foot strike patterns and softness of shoes. In order to measure differences of impact accelerations related to pavement types in running foot strike, this study conducted a field running test employing special shoes containing a wireless motion sensor in the shoe sole. Wearing the shoes, four recreational runners ran a flat 800-meter course which has four types of surfaces, namely, grass, interlocking block pavement and two types of asphalt concrete, at a speed of 10 kilometer per hour. According to the measurement results by the motion sensor in the shoe sole, peak impact acceleration is larger in the case of harder surface, and the difference by the surface type is more noticeable on the horizontal acceleration, or the running directional component of acceleration, than the vertical acceleration.

 The demand on developing pedestrian spaces is recently increased to realize road environment which enriches local societies. This study discusses evaluation of road surface properties by the dual-tree wavelet transform which is able to implement directional multiresolution analysis applied to three-dimensional point clouds acquired with a terrestrial laser scanner. The result shows that typical surface irregularities on pedestrian zones are distributed in specific wave bands and directions in terms of the wavy characteristics of surface properties. Finally, this study proves the capability of the directional multi resolution analysis by the dual-tree complex wavelet transform enabling the identification of definite areas of surface irregularities which require maintenance and rehabilitation in the three-dimensional point clouds of pedestrian zones.

 It is important to improve the environment of pedestrian space that everyone can use with confidence. The main problem of road surface evaluation for maintaining and managing pedestrian spaces is subjective evaluation, because it is difficult to apply road surface condition measurement vehicles because vehicles cannot enter. In addition, since the IRI is calculated based on a model for automobiles, a method different from that for automobiles is required for road surface evaluation in pedestrian spaces. In this study, we conducted a running test using Four-wheel mobility scooterers and clarified the vibration response related to ride comfort during running. In addition, using a 3D point cloud measurement system developed as a new road surface survey method for pedestrian spaces, we verified the accuracy of road surface evaluation considering the vibration response of personal mobility. As a result, it was confirmed that the road surface can be acquired with high accuracy in the measurement accuracy in the height direction and in the evaluation.

 The road administrator routinely inspects pavements, however, the need for repair depends on the inspector's experience and knowledge, and the lack of skilled inspectors has made improving the efficiency of inspection work an urgent issue. As a solution to this problem, previous studies have diagnosed pavement damage during driving by using probe data that record the driving position and acceleration of vehicles. On the other hand, if probe data can be collected at the same time as daily inspections, it will be possible to identify damaged areas through damage diagnosis, analyze data trends over multiple time periods to understand the progress of damage, and predict future damage.

 In this study, we attempt to apply LSTM, which is good at classifying and predicting time-series data, to the extraction of damage locations and damage prediction. As a first step, we constructed a pavement damage diagnosis model using LSTM and confirmed its usefulness with a damage extraction rate of about 80%.

 In Hokkaido, which is a cold region with snow, many potholes occur on the road surface during the thawing season due to deterioration of the pavement. In this study, the following points were carried out using the point cloud data of the paved road surface acquired by the Mobile Mapping System. We found the characteristics of the altitude value of the place where the pothole (baby pothole: BPH) that does not affect vehicle running.. Estimating trends in road surface water represented by running and stagnant water on the road surface . By collating these with the positions of BPH, the risk of BPH progressing to PH was evaluated on a 5-point scale. Furthermore, based on the obtained results, we proposed a method for evaluating the risk of PH occurrence from the point cloud data acquired by MMS.

 In Japan, the efficiency of pavement inspection is being actively promoted. For the IRI measurement, simple accelerometers and AI are being introduced. In this study, we developed a simple IRI measurement system using multimodal AI with inputs of vertical vibration acceleration, driving speed, and crack ratio obtained from a commercial camera. First, an IRI estimation model using Elastic Net was constructed, and it was clarified that the crack ratio and driving speed contribute to the estimation accuracy. In the validation test of proposed system, it was shown that the detection rate (damage level II+) and the hit rate (damage level II+) were the highest rank A, and the hit rate (damage level III) was rank B. Although the detection rate (damage level III) was rank C, the data expansion using SMOGN was shown to be effective as a measure to improve accuracy.

 The length of the expressway operated by NEXCO-West has reached about 3, 500 km, and half of them have been in service for more than 30 years. In order to provide safe, secure, and comfortable pavement condition, pavement repair measures that can extend the service life of pavements should be developed based on the effective use of monitoring information. Pavement monitoring is classified as routine inspections by daily patrol and road surface condition surveys every 1 to 3 years. Maintenance including crack sealing and patching are planed based on the results of daily inspections, and rehabilitation as cutting overlays, are planed based on the results of road surface condition surveys, each of which is managed independently. Therefore, the information from daily inspections may not be fully utilized in the rehabilitation planning. In this study, we analyzed the deterioration trend of expressway pavements by linking daily inspection data, road surface condition survey data, and as-built pavement information based on location information such as routes, lanes, and kilo-posts. Through this analysis, the quantitative evaluation method of pavement damage using information obtained from the road surface is examined, and the method of formulating repair measures according to the progress of pavement deterioration is discussed, as well as the direction toward a longer repair cycle based on the importance of the asphalt layer thickness.

 Road managers must effectively perform operation and maintenance under stringent conditions that include shrinking budgets and a shortage of engineers. In this study, an AI-based pavement inspection and diagnosis system that we had previously developed was applied to a wide range of roads in Hokkaido, and the degree and causes of cracking were investigated. As a result, points for improvement in the system were discovered for cases where the cause of cracking was difficult to determine, and the characteristics of pavement cracking in Hokkaido were identified. Furthermore, assuming maintenance and repair methods corresponding to the degree and causes of cracking, maintenance and repair costs were estimated for the surveyed roads. The results show that this method allows for comparison between regions at the network level and between roads at the project level in terms of the required maintenance and repair costs.

 Frost damage, which is thought to be caused by freezing and thawing, has occurred in some of the slab track filling layers. Although previous investigations have confirmed that the frost damage range is wider at the corners than at the sides, the cause of this damage has not been fully elucidated. In this study, temperature change tests were conducted on slab track specimen to measure the temperatures inside the filling layer. As a result, it was confirmed that the freezing range of the corner was wider than that of the side. As a result of reproducing the temperature change of the specimen by unsteady heat conduction analysis using finite element analysis, it was clarified that the freezing range of the corner spreads due to the influence of the temperature transmitted from the side and end faces of the specimen. In addition, unsteady heat transfer analysis was also performed for the analytical model of the slab track, and the range of the filling layer that may be subject to frost damage was indicated.

 Asphalt pavement is constructed in multiple layers due to design requirements and construction constraints. Pavement interlayer delamination accelerates lowering the bearing capacity and structural failure; consequently often leads to serious local damage. However, here are few survey cases and the test evaluation method is not clear, because interlayer delamination is difficult to identify because it is difficult to investigate from the road surface survey. This research note introduces a case of detailed investigations at an in-situ delamination site, and discuss the applicability of various non-destructive test methods that were tried at the investigation.

 In recent years, it has become necessary to conduct detailed survey of asphalt pavements that have been damaged prematurely, to diagnose the soundness and damage, and to take measures based on the results to prevent the pavement from deteriorating prematurely again. However, it is difficult to develop a manual for detailed survey because the factors causing premature deterioration of pavements vary from site to site.

 In this study, a detailed survey was conducted in a deteriorated section of an in-service national highway, and it was shown that the following three steps are effective in the detailed survey to clarify the causes of early deterioration: Step 1 "formulate a hypothesis of the causes of early deterioration", Step 2 "determine the detailed survey spots and methods," and Step 3 "verify the hypothesis through detailed survey". In the detailed survey, a combination of FWD testing, core sampling, and excavation survey can be used to investigate the causes of complex damage that occurred in the early-stage deteriorated sections.

 The Subcommittee on Pavement Materials of the Committee on Pavement Engineering of the Japan Society of Civil Engineers conducted CBR testing and resilient modulus testing using sandy soil as simultaneous tests to study the strength and deformation characteristics of subgrade soils. The results showed that not only the moisture ratio but also the dry density had a significant effect on CBR, since its variation at the same dry density was great. Resilient modulus was also found to be greatly affected by dry density and moisture ratio as in the case of CBR. The relationship between CBR and elastic modulus was examined in domestic and foreign studies, including the results of this study, and it was found that the elastic modulus was widely distributed within the regression line of 5×CBR to 20×CBR for the same CBR.

 This study proposes new pavement structure for roadway rainwater runoff control which is expected to be alternative to permeable pavements. The proposed structure collects surface rainwater to roadside ditch and leads it laterally to granular subbase course through inlets on the wall of the ditch. One expected advantage of this structure is that it allows inflow only during peak-time of rare big floods such as several-year-return period. It may solve the problems on mechanical durability, flood control efficiency, maintenance and groundwater and soil environment that are major concerns in permeable pavements. The authors conducted hydraulic model experiments to investigate basic lateral inflow characteristics to granular subbase course. Number of inlet holes on the ditch wall and their locations were varied in the experiment. The results showed that regardless of the number of inlets, the amount of inflow into the roadbed affects the water table difference. It was also found that grain size of subbase course material affects horizontal permeability because it changes the pore system, but does not significantly affect the ability of the roadbed to store water because the porosity itself does not change.

 This study has conducted a small model experiment to visualize erosion process of granular subbase course material due to pavement pumping. The experiment requires video processing technology that automatically tracks the movement of the subbase course material at the particle level. Therefore, this study developed a method to track the particles during the pumping experiments using fluorescent paint-dyed particles and a black light. The experimental results showed that the paint-dyed particles showed sufficient luminance in the video, and that automatic tracking was possible. In the pumping model experiment, it was found that dyed particles just below the joints showed significant settlement behavior in the early stage of wheel-loading, and that the settlement converged as the number of cycles of loading increased. Furthermore, it was confirmed that the horizontal trajectory of the particles moved in the direction of the joints.

 To reduce CO₂ emission and achieve long-life pavement, this paper focused on cement asphalt emulsion stabilization (CAE) mixture as base course material and evaluated its applicability.

 According to the various test results and the calculation of CO₂ emission intensity, it was found that CAE mixture is more effective than other base course materials. In addition, for the purpose of expanding the application of CAE mixture, the issues of CAE mixture were extracted using SWOT analysis. As a result of this analysis, it was found that the issues are lack of awareness and lack of manufacturing bases.

 In this paper, the following methods are proposed to solve these issues. For increasing awareness, the evaluation method using a two-axis graph (positioning-map) is effective because it is visually easy to understand. And for eliminating lack of manufacturing bases, it is effective to divert existing similar plants.

 Glass foamed lightweight geomaterials are recycled lightweight materials made from waste glass. When using lightweight glass foam as a geomaterial in cold regions, it is necessary to confirm its resistance to freezing and freezing and thawing, but there are very few cases in which these properties have been investigated. This study examined the applicability of glass foamed lightweight materials to cold region by conducting freezing tests and heat transfer analysis. The lightweight geomaterial was a non-freezing material and of good quality with no decrease in CBR value after freezing and thawing. It was also confirmed that there were many pores within the particles, and the effect of this was to show that the thermal properties of the material were superior to those of ordinary crushed stone. Furthermore, the effect of using lightweight geomaterials for control frost heave layer and subbase course on frost penetration depth was clarified by heat transfer analysis.

 The road bridge slab waterproofing handbook states that the slab waterproofing layer should not be applied immediately after rainfall or within two weeks after placing the concrete slab, due to concerns about a decrease in adhesive strength due to residual moisture. However, in the case of large-scale repair work being carried out on the Hanshin Expressway, it is not realistic to secure a two-week process to reduce the moisture content. Therefore, in this paper, using simulated concrete slabs for which several types of base preparation methods were tested, the effect of the unevenness (surface roughness) of slabs on changes in slab moisture content over time was investigated. The effect of the surface roughness and water content of the floor slab on the performance of the waterproof layer was evaluated by the adhesion test using.

 In order to ensure the long-term durability of road bridge concrete floor slabs, it is necessary to install a floor slab waterproof layer. It is thought to be affected by the texture depth of the upper surface of the concrete slab. In the Hanshin Expressway, the floor slab surface is partially over-cut during pavement repair work due to unevenness of the floor slab, etc., and unevenness is currently occurring on the surface of the floor slab. Due to this unevenness, there is a possibility that the film thickness of the floor slab waterproof layer is partially thinned, and sufficient waterproof performance cannot be secured. In this study, in order to set the reference value for the texture depth of the floor slab upper surface from the viewpoint of ensuring the film thickness, the asphalt coating film was applied to the texture depth of the floor slab upper surface when various surface preparations were performed after pavement cutting. We report on the results of examining the relationship between the film thickness and its perfomance when the waterproofing material is applied.

 The authors studied a method for evaluating concrete surfaces, focusing on air permeability and moisture content, in order to reduce defects related to adhesion between the waterproofing layer and the concrete surface. Specifically, concrete specimens with different air voids and water content conditions were prepared, and the surface properties of the concrete were evaluated by air permeability tests and a newly devised asphalt pouring test.In addition, tensile adhesion and blistering resistance tests of the waterproofing layer were conducted to evaluate the effects of different pore voids and moisture content of the concrete on the waterproofing layer. The results showed that if the air permeability is large and the number of asphalt swellings is high, the tensile bond strength may decrease, resulting in pinholes and blistering of the waterproof layer. It was also found that curing the concrete to increase its denseness may reduce the defects in the adhesion between the concrete and the waterproof layer.

 In order to improve the waterproofness of concrete decks, the application of Guss-asphalt pavement, which has a thick waterproof layer and can omit the waterproofing work itself, is being considered for concrete decks. However, Guss-asphalt pavement is not versatile because it needs special construction machines. Therefore, on the premise of using a general paving machine, the authors have developed a construction method to construct asphalt pavement on site with high waterproof performance as well as that of gussasphalt. In this method, a large amount of thermoplastic resin waterproofing material is applied to the bridge deck in advance. After cooling to room temperature, the resin waterproof material is melted by the heat of paving the asphalt mixture, and the resin waterproof material is permeated and filled from the bottom of the asphalt mixture. In this paper, the air void ratio and water permeability of the developed method were compeared with an asphalt-based waterproofing material and a Guss-asphalt mixture. As a result, the optimal amount of resin waterproofing material is 2.0 kg/m², and at this time, voids of the asphalt mixture at 20 mm from the top of the decks decreased to 1.0%. which is lower than that of the Guss-asphalt mixture.

 80% of Hanshin Expressway consists of viaducts, and Wangan Route has lots of steel deck structures. For the base layer of pavement on a steel deck, a goose asphalt mixture has been conventionally used because it has high followability of steel deck deflection, and well workability by pouring to fill into uneven parts on the deck. In recent years, road pavement companies have developed new goose asphalts that are more durable and lower odor than conventional goose asphalt mixtures, and put them into practical use. On the other hand, there are no performance-defined evaluation standards for the highly durable goose asphalt mixture of the base layer mixture on a steel deck in Hanshin Expressway. In this paper, proposed performance regulations for this new asphalt mixtures are reported by evaluating the results of highly durable goose asphalt mixtures and a conventional mixture in various performance tests.