The purpose of this study is to contribute making a technical guideline for the road administrators who are responsible for user s needs. In this study, road profiling by a high-speed profilometer is conducted over the expressways in Japan and the evaluation of road evenness is established using the roughness indicators such as IRI and RN. Furthermore, we studied the subjective evaluation of ride quality by means of a rating panel for the expressways. Finally, the dynamic behavior of the vehicle on the rutted road is examined by the lane change test experimentally and by use of a dynamic simulation model of the vehicle theoretically.

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The SMTD (Sensor Measured Texture Depth) measured by Mini Texture Meter and BPN measured by the British Pendulum were used to estimate the coefficient of skid resistance and the estimated values were compared the measured skid resistance on expressways to testify the applicability of texture to the monitor of pavement surface. As the result, followings were made dear;(1) it is possible to apply the texture for monitoring dense-graded asphalt pavement, (2) it might be applicable the texture for monitoring semi-rigid pavement considering the limited number of data, (3) it is not possible to apply the method which is applicable to dense-graded asphalt pavement for drainage pavement due to the extraordinary large macrotexture and measurement technique.

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The Circular Texture Meter (CTM) recently developed is a device which has a CCD Laser Displacement Sensor mounted on an aim designed to rotate on a circumference of 142 mm radius. The CTM can measure the texture with about 0.9 mm pitch on the same circumference of that coefficient of friction is measured with a D. F. Tester.
In this study, we have analyzed the relationship between MPD by CTM and MTD by Sand Patch Test. Also, we have measured the coefficient of friction with D. F. Tester at the same spots as that the texture was measured by the CTM.
We have observed a good correlation between the MPD by CTM and the MTD by the Sand Patch Test. And it is found that International Friction Index can be computed from the CTM measurements and the D. F. Tester measurements.

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This research aimed at the improvement of the function of the low noise pavements. Material and thickness of the pavements were changed and a lot of examination was executed on the actual road. Various noise measurements were carried out and the noise decrease function was evaluated. According to these estimations, the application of the low noise pavements to the street of Tokyo Metropolis was examined.

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The acoustical properties and model of porous pavement is discussed in this study. The acoustical properties of porous pavement are quite different from that of the sound absorbing material such as glass wool and urethane foam because of the structure. The acoustical model, acoustic impedance model, used for the sound absorbing material is not suitable for porous pavement. The acoustic model for calculation of sound propagation on porous pavement is newly developed in this study. This acoustic model is the element model of the Finite Element Method based on the structure and acoustical properties of porous pavement. It is shown that this model gives a good fitting to measured acoustical properties and applicable to calculate sound propagation on porous pavement.

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The sound propagation over the porous pavement surface is discussed in this study. The sound propagation over the porous pavement is calculated by the finite element method (FEM) using the acoustical model of the porous pavement. The sound reduction while propagating over the porous pavement surface, called excess attenuation, is evaluated and found out the effect of porosity, thickness and aggregate size. Since the measured sound reduction of the porous pavement commonly used in Japan is 3 to 5 dB and the calculated attenuation value is around 1dB, the sound reduction effect of the porous pavement is mostly depend on the sound gen rating mechanism between the tire and the porous pavement surface.

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The intensity of compaction in railway embankment is controlled by K₃₀-value in the plate loading test. However, the plate loading test takes much time and needs a large reaction equipment. Therefore, FWD was examined as a convenient method and substitution for plate loading test. As a result, K-value from FWD correlates with K₃₀-value, and it was confirmed that FWD could be applied to control compaction degree. For the purpose of using FWD practically as controlling compaction degree of embankment, test results was classified into every type of the soil, and relationship between rigidity of subgrade, K₃₀-value and K-value from FWD was summarized. As a result, it was found out that the relation between K-value from FWD and K₃₀-value were 1:1 when the rigidity of subgrade is low, also its relation became 1:2 when the rigidity is high.

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FWD tests have been carried out for these four years at the testpit, whose bearing capacity was designed for D traffic. The measured deflection basins were statically back-calculated and failure analysis was performed by Asphalt Institute's formula. From the measured deflection and the back-calculated layer moduli, and furthermore, the calculated cumulative traffic passes to the failure by fatigue crack and rutting, the following results were obtained, 1) the measured deflection becomes smaller year by year, 2) the back-calculated modulus of the asphalt layer is larger as the years go by, 3) the calculated cumulative traffic passes to the failure tend to be bigger and the fatigue crack is more critical, as the asphalt itself becomes harder due to ultra-violet and other aging factors.

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An axisymmetric model to represent pavement is employed in the most backcalculation software currently available. However FWD test is sometimes required at a location where the axial symmetry is not applicable. It is investigated in this paper how the distance between FWD test location and pavement edge affect surface deflections using 3-dimensional finite element analysis and what backcalculated layer moduli will be if a current software is used on them. Furthermore the relation between a speed of surface wave propagation and FWD location is also examined. It is found that when as the test location gets closer to pavement edge; 1) surface deflections abruptly increase, 2) the estimated base modulus is greatly affected, and 3) the velocity of surface wave propagation is little affected.

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This paper describes properties of SHRP LTPP deflections using FWD and investigates the dispersion and variable of deflection data. From the results of the analysis, it was found thatdeflections collected from test section showed normal distribution and sensor 1 deflection was increased with time gradually.
Furthermore, a simplified deflection-based flexible pavement design procedure was proposed.

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In general, ballasted track needs periodical track maintenance work, because ballast bed is gradually destroyed by repeated trainloads. Enormous expenditure is therefore necessary to maintain track in good conditions. In addition, it is increasingly getting difficult to obtain maintenance workforce, because Japan is quickly shifting to a society of elders, and people tend to hate tough works such as manual track maintenance work. Under these circumstances, a low-noise solid-bed track on asphalt pavement for new railway lines was developed to reduce the maintenance work. This paper describes the track structure, the results of the performance tests of this track and basic design.

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Structural evaluation of pavement has been conducted from a set of surface deflections measured by a fallingweight deflectometer (FWD). However, because a backcalculation requires repetitive computation, layer modulican not be estimated instantaneously after FWD tests. This study aims to overcome this shortcoming.
Selecting three layer pavement as an example structure, artificial neural network is trained to acquireknowledge on relationship among layer modulus, layer thickness and surface deflections. The systemconstructed in this manner is verified by applying the system to FWD test data and by comparing the systemgenerated layer moduli with those obtained from backcalculation.

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The crack is caused on the surface of the overlay layer at an early stag-e by the movement of the pavement with the temperature change in the pavement and the traffic load. When the method in which the crack arises on the surface in this overlay layer is delayed, there is a method for using the Stress Absorbing Membrane Interlayer (SAMI) for the intermediate layer. The test which simulated the horizontal movement with the effect of the overlay using the SAMI was carried out.
As a result, it becomes clear that stress absorbing effect of SAMI and stone matrix asphalt (SMA) are high for the horizontal expand and contract test. In addition, the investigation data of experimental pavement was analyzed by the finite element analysis (FEM) and the prediction procedure of the necessary overlay thickness was also examined from the FWD measurement result in the field.

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A condition survey was conducted to investigate surface condition of pavement on steel plate deck of bridge. The results of the survey showed that main distress mode of the pavement are longitudinal cracks which occur at web of longitudinal rib as well as at the position between the webs. To make clear the causes of the crack, we performed strain analysis using overlaid FSM. The strain analysis indicated that, although large tensile strains appeared in the pavement at the web of rib, the strains between the webs were basically compressive. These results can not explain the cracks between the webs. Laboratory experiment modeling the pavement on plate deck was conducted and the results indicated the possibility of occurrence of the cracks by repetition of compressive strain.

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The structural model for pavements on steel plate deck should be able to deal with structure of the steel plate deck as well as pavement structure. This paper presents a structural model using the strip element and prism element. In this model, the steel plate deck is modeled by the strip element and the pavement is divided with the prism element. The strip element and the prism element are connected with a link element. This model is able to analyse the local deformation of pavement, particularly with low stiffness. The validity of the model was verified with numerical examples and comparisons with the experimental results obtained on an actual pavement on a steel plate deck.

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In Japan, cement and formed asphalt stabilization has been used very often lately. In this mix design, we must use a special formed asphalt production device for making a stabilized material. The purpsse of the present investigation is to compare the characteristics of cement bituminous stabilized material using various bituminous, and to simplify mix design. In this report, the authors studied the method of mix design using asphalt emulsion and bubbled asphalt which make admixture, and the substitute method of mix design is explained.

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We studied the suitability of recycled asphalt concrete aggregate as subbase course material and frost blanket material in cold regions. We found that such material can be used as subbase course material if quality is carefully controlled through frost-heave tests and if the mixing ratio satisfies modified CBR standards. When such material was used in the frost blanket at a rate of 100%, temperature effects were not observed and bearing capacity did not decrease, thus confirming its suitability for use in the frost blanket

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The authors have been studing on the technical improvement for hot as phalt mixture generally used aspavement material, from the point of view of the global warming and environment conservation. The purpose is the development of a new technology of low heat asphalt mixture enabled to reduse heating temperature at production stage and pavement work. As the result, it was considered that the more temperature reduction is required to enhance the effect of low-heat asphalt mixture. Based on the developed technology, a method enabled to reduse the heating temperature about 50-60°C has established. And it is confirmed that the same quality and execution compared with usual hot asphalt mixture are given by using the improved method.

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Durability of pavement is a fundamental technical issue. The Chuo Expressway Fuchu Pavement Section has been in service and in good condition for more than 20 years without any repair work. The reason for high durability of this pavement was investigated analytically and experimentally. It is concluded that the key is the proportion of asphalt mixture of the surface course. Our calculation formula for appropriate voids in mineral aggregate proposed in another paper was introduced to the asphalt mixture design. This procedure is also applicable to a variety of pavement mixtures, and universality of the calculation fomula is further demonstrated.

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Recently, the capacity of landfills for waste becomes considerably inadequate. Therefore, the ash of domestic wastes is to be melted in order to reduce its volume and this molten slag is to be recycled. In this paper, the use of molten slag is mentioned, especially for paving materials such as fine and coarse aggregates and granular materials. The improvement of slag properties is also studied by using antistripping agent.
As the results of using three types molten slag, these molten slag are found to be able to use as a paving materials without any toxic substance liquefied out.

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Bicycles are used many peoples in town load, but very few studies have been conducted on bicycle track pavement. We evaluated the braking evaluation and tractive resistance for bicycle and pedestrian track on the 4 rubber pieces pavements and 2 asphalt pavements, using of the testing method for the making of bicycles. The skid resistance, elasticity and permeability were examined for the sidewalk evaluation. There was conceded that this testing method was able to evaluate of the pavement materials for bicycle and pedestrian track, and it was the best mix proportion to make the bicycle and pedestrian track, that was Granular rubber=50%-30%.

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The field observation was continued to estimate the thermal radiation from asphalt pavement. The surface temperature, solar radiation, infrared radiation, temperature, humidity, wind velocity and precipitation were observed for a period of about 8 months including summer and winter. Surface temperature, solar radiation and infrared radiation measured were compared with that of calculated using multiple regression analysis equations, surface temperature and the radiations were estimated within 5°C and 50W/m². The equations are able to estimate the total heat flux (=infrared radiation + reflected solar radiation + sensible heat transportation) from pavement surface and showed a good correlation with the measured.

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Ari analysis of rutting depth on expressways was conducted and it was made dear that the Dynamic Stability (DS) of moru than 800 should be a target value to plastic flow rutting on expressways with daily heavy traffic volume of less than 5000 vehides in one direction and the DS of more than 2000 to restrain plastic flow rutting on expressways with daily heavy traffic volume ofless than or equal to 5000 vehides. Tests to determine the property of modified asphalt cements was conducted with the Accelerated Pavement Testing Machine, and fallowing properties were found tobe desired to have enough resistance to the plastic flow rutting-, softening point of60°C, viscosity at 60°C of more 1000pa·Es, though more data are required.

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This paper describes an application of performance analysis based on the results of circular road tests to actual asphalt pavements. The performance of the test pavements was investigated in the eight lines in Hyogo Prefecture; in all the test pavements, compound slag and HMS were used as the upper basecourse. The serviceability indices calculated from the performance analysis were compared with those derived from actual measurement. It is shown that the serviceability calculated from actual measurement is generally in good agreement with the analyzed performance curves for the sections designed for the traffic types A and B, although some scatter is recognized.

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To construct the highly durable pavement is very important in airport asphalt pavements, because the pavement has to support nearly 400tf of aircraft weight. It is effective for this case to use the asphalt mixture that has a high stability in the surface and/or binder course, and one of promising mixtures is the large stone asphalt mixture. In this paper, applicability of the large stone asphalt mixture in the surface and/or binder course of airport asphalt pavement was evaluated by carrying out laboratory tests and field loading test. From the discussion of test results, it was confirmed that if the maximum size of aggregate is about 30mm the large stone asphalt mixture could be applied in the surface course and/or binder course.

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Nondestructive structural evaluation method of airport concrete pavements using FWD with 200kN is described. The method consists of two phases; one is to estimate both elastic coefficient of concrete and coefficient of subgrade reaction based on measured deflections at slab center, and the other is to evaluate structural integrity, load transfer effectiveness and voids underneath slab, based on the deflections at joints and cracks. In the process of this development, deflections measured at various airport pavements in service and some experimental pavements have been analyzed, and then practical criteria are described after comparing with the current procedure.

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In composite pavements, such as whitetopping and overlay, it is important to ensure the bond between asphalt layer and concrete layer for long-term performance of the pavements. The bond strength is expected to be influenced by characteristics or texture in the interface between asphalt layer and concrete layer. So, we have been searching a method to make the optimistic interface characteristics. In this study, we have tried two types of method for surface treatment using water jet: one with high pressure and large amount of water and another with super high pressure and small amount of water. We investigated the relationship between the interface texture and bond strength, varying operational parameters including water pressure, operation speed and amount of water. As the results, it was found that there is an optimum value of a parameter, which was introduced to express the energy of water and is a function of the operational parameters, to obtain high bond strength

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There is a method to place thin cement concrete overlay on an asphalt concrete pavement as one of the rehabilitation methods for improving an existing asphalt pavement. However this method doesn't become popular at present. In this research, to begin with, applying the theory of a beam on Winkler foundation, we will investigate the stress analysis procedure of pavement slabs. Next, we will investigate the model of composite structure that consists of a thin cement concrete layer and an existing asphalt pavement layer, taking the degree of bond between these two layers into consideration. As the result of measurement of strain at the bottom of a thin cement concrete overlay, we confirmed usefulness of this calculation method.

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Pavement using porous concrete is expected to be a promising technique with high drainage capability and low-tire/road noise property, because of its high porosity. In case porous concrete is applied to a rehabilitation technique of an existing pavement, thin bonded overlay on both ordinary jointed concrete pavements and asphalt pavements is thought to be a practical method, because most of the rehabilitation job does not allow the high raise of formation. In this technique, the bonding is the important key to success; therefore fundamental experiments and the following fields test regarding bonding were executed. In conclusions, bonding can be got through a suitable selection of bonding material and an adoption of appropriate surface treatments on the existing layer. In addition, full-depth porous concrete construction method is applicable to the thin bonded rehabilitation only with applying the bonding material in advance.

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