In the theoretical design of pavement, strains that occur in pavement layers are obtained by a mechanicalanalysis and the number of years to fatigue failure is estimated based on the fatigue characteristics of materials. It is very important to accurately estimate the strain induced by traveling vehicles. In this research, the residualstrain was measured in an indirect tension test, and calculation of strain from this measurement was studied. The strain generated in the asphalt mixture layer by traveling vehicles was calculated using multilayer elastictheory analysis, and a correction that considers residual strain was performed. The correction was examined bycomparing the results with measured strain caused by traveling vehicles.

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A series of research works on an introduction of snow-melting equipments to airport asphalt pavements were conducted to prevent air traffic disturbance due to snow and ice. The laboratory tests show that the snow-melting equipments do not affect the deformation and dynamic stability of the asphalt concrete layers. The loading tests on the experimental pavements having snowmelting equipment show that the deflection and rutting of pavements are scarcely influenced with the type and installation depth of snow-melting equipments. Although the accumulated deformation of layers increases as the depth becomes shallow, 3-D finite element analysis shows that the stress of snow-melting equipments caused by aircraft load is sufficiently small against the strength. It is concluded from the above that the snow-melting equipments might be installed successfully to airport asphalt pavements.

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Partial plastic flow of porous asphalt surface course and particles of binder course mixture blowing up from its porosity, due to stripping of the underlying mixture have been observed. Judging from serviceability surveys of porous asphalt in heavy traffic sections of a Japanese expressway, it was found that its underlying layers are more likely to be damaged in mountainous sections with higher annual rainfall and shorter annual daylight time. Asphalt layers in such problematic sections would be damaged in strength of stiffness.

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To develop a method to predict when and how longitudinal surface cracks (LSC) occur in pavements on steel bridge decks, the effect of tire load model on horizontal strains and dissipated energy on the pavement surface was investigated. Two types of tire loads were considered: the vertical pressure model and the vertical and horizontal pressure mode. The horizontal pressure is supposed to be generated by the stiffness of tire ribs and friction between the tire and pavement surface. Strain distributions computed with the tire load models in SLPE model were compared with the measured ones. It was found that computed strains with the vertical pressure model agree well with the measured ones. Also, the positive relationship between length of LSC observed in actual pavements on bridges and fatigue damage estimated based on the dissipated energy theory and vertical pressure model was obtained.

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In the theoretical design procedures, stresses and strains in a pavement should be made clear. Therefore, we carried out the moving load tests on a trial-paving yard, using accelerated vehicle simulator. From a result of our study, the following conclusions were obtained, a) The deeper the position was in the pavement, the wider measured stress was distributed. b) The stress and strain under the moving load were very similar to those under the FWD load. However, the stress and strain of the static load were greater than those of the moving and FWD loads. c) Fatigue in the sub-grade was caused by repeated moving loads. But, the degree of fatigue was not captured by the deflection DO of FWD load.

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The structural capacity of flexible pavements is greatly influenced by the stiffness of the asphalt concrete layer. The asphalt layer stiffness is a function of temperature and changes every hour through a year. The relationship between the stiffness of asphalt layer and its mean temperature has been presented in the exponential form. In this paper, an asphalt layer is broken into thinner layers and assigning temperature to these layers by using the conventional model. Then the parameters in the type model are determined by matching the surface deflections with FWD deflection bowl.

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In recent years, large forklifts with heavy wheel load are increasingly introduced to the freight container yard. In the current design of freight container yard pavement, theoretical design method based on multi-layered elastic analysis is applied. However in the case of freight container yard, wheel loads of forklifts are significantly larger than the traffic loads on the roads. To investigate the deformation characteristics of asphalt pavement under heavy wheel load, moving wheel loading tests were carried out On the other hand, ground contact area of forklift tires change with carrying containers. Because the tread of forklift tire is greater than the thickness of pavement, strain in the pavement is significantly influenced by ground contact area. In this study, FEM was introduced to estimate the effect of ground contact area on the strain in the asphalt pavement

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This paper presents a simple method to estimate cyclic plastic deformation of ballasted track subjected to repeated train passages in terms of the strength and deformation characteristics of coarse granular materials. A new analytical procedure with linear elastic FEM analysis considering the cumulative strain derived from element test results of ballast was proposed, and it was revealed that the analytical procedure could roughly estimate the residual settlement of railroad ballast, which is an assemblage of poorly-graded crushed stone, by simulating small scale model tests of ballasted track.

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The pavement design using analytically or mechanistic-empirical based methodologies is now replacing the empirical one. To make the analytically based design advance, comparative study of measurement with prediction on dynamic response of pavement has been done. To effectively backcalculate the material properties of pavement, the Ritz vector is introduced, and the requisite number of Ritz vector needed in the forward and sensitivity analyses is adaptively determined in the developed program. The material properties of constructed layers for pavement can be backcalculated from the FWD test data. Moreover, the predicted surface deflections, soil pressure, and strains are in good agreement with the measured ones for the prepared pavements. It is confirmed that the developed FEM program has adaptability to the tested pavements.

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“Technical Standard for Pavement Structure” was published in 2001, and the indispensable performance index with which pavement should be equipped was shown. However, the concrete method was not shown about the “number of wheel passes causing fatigue” which is an index showing the performance of the whole pavement structure. Then, its attention was paid to FWD which can evaluate the structure of a pavement object easily there, and it inquired using the long-term investigation data of the asphalt pavement in a national highway. Consequently, it turns out that the number of wheel passes causing fatigue of pavement can be presumed from the deflection (D0) of the road surface after construction.

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New structural evaluation system for airport pavements using deflection data measured by FWD was developed. Since conventional evaluation system could not conduct structural evaluation for pavements in small airports, could not evaluate deflection data using FWD with load smaller than 200 kN, and could not be used in some computers due to problems, it was improved to solve them and it adopted BALM and GAMES to improve calculation accuracy. Furthermore, thickness of concrete overlay on concrete pavements could be calculated if necessary.

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This study proposes a new evenness management method for road users taking into account momentary riding comfort. We contend that if the vibration of each point can be suppressed, then the overall riding comfort can be improved. This method uses the calculated localized IRI to determine the points that exceed the management target; therefore indicating which the priority in section of the road requires repairs most. Localized IRI can express the influence of severe roughness that the past section evaluation value (IRI) can not appropriately expressible. This study indicated the management target value at each running speed to suppress the vertical acceleration of sprung mass to single amplitude of 2.5m/s² based on the full-vehicle simulation results.

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Urban River Inundation Prevention Act is enforced in May, 2004. It is necessary to build pavement with runoff control capacity such as permeable pavement in the roadway in designed area by this law.
But, it is not confirmed that permeable pavement has enough durability as pavement. So, the factor and counter measure that influenced durability for permeable pavement were examined by indoor examinations, full-scale pavement test and examination pavement in roadway.
By these results, it is cleared that influence for durability of permeable pavement is difference by the kind of subgrade soil. And it is necessary to drain rainwater or add the thickness of pavement when subgrade soil is clay.

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Arrival and departure lines are necessary over 500m per 1 line over the extension for container yard of the railway freight facilities of the arrival and departure line cargo handling system. In addition, the area of container yard becomes about 1.5-2.0ha for disposal of goods by the forklift for the width of container yard of the 2 plane type, since they are necessary over 40m. And, the effect on the flood given to urban river and sewerage must be minimized, since it is constructed for the good position of the access with the urban highway as a node of modal shift of the traffic from the concept.
Then, drainage mixture which can resist the load of the forklift has been developed. Here, the field spray test was carried out, and strength and thickness design, design method of the infiltration facilities and infiltration capacity of the reservoir base course were verified.

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A series of laboratory tests were conducted on the large stone asphalt mixture. The tests were also carried out on the conventional type asphalt mixture. Based on the test results, this paper focuses the effects of air void ratio of the large asphalt mixture on the bending strength/deformation, the raveling and the asphalt deterioration characteristics. Then the characteristics are compared with those of conventional type asphalt mixture to be applicable for airport asphalt surface-base layer.

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In Osaka International Airport. It was necessary to reconstruct asphalt layer (28cm) of B taxiing way.However, on the airport under use, there was a technical problem in reconstructing in the asphalt layer of the 28cm thickness.Then, we examined the rapid construction method that will be able to open next morning.It reports on the application of “Thick Lift Method” that used “Large Aggregate Hot Mix Asphalt” for rapid reconstructing of the thick asphalt layer.

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This paper investigates the cause of asphalt pavement blistering at New Chitose Airport by reproducing the blistering phenomenon in indoor tests using conditions of the site. Blistering was found to be affected by void content and pavement temperature. This paper reports on a blistering countermeasure in which type-II modified asphalt is installed as the surface course, and on a blistering countermeasure in which the number of asphalt layers is decreased but their thickness is increased from those in conventional pavement.

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Air-pumping noise generated by a road cavity is studied by an experiment using of an inner drum facility. To simple the problem, the road cavity is modeled as a cylindrical cavity which is processed on the drum surface, and acoustical wave is observed after a tire passed through the cavity. For the difference of the cavity size and the tire velocity, the characteristics of maximum sound pressure and averaging frequency are clarified. The fact that air-pumping noise by the cavity is reduced at the road with the porosity like the drainage asphalt pavement is verified experimentally.

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An increase oftire/road noise level was measured as the surface roughness of porous pavement decreases under its auface treatment The new surface evaluation method by micro-texture based on wearing out of asphalt-mortar and clogging condition is proposed assuming nonmovement of the coarse aggregates. The result of the text= analysis shown the existence of the non-movement duration of the aggregates, then it is confirmed that the proposed method can evaluate the changes of micro-texture and that an adequate correlation between the changes of microtexture and the dynamic friction coefficient And then, it is estimated that the increase of tire/road noise level after surface treatment is generated by the sfick-slip phenomena of tire tread block.

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Two layer type low noise pavement has many combinations depending on the kind of the compound used for an upper and lower layer. In this thesis, it was examined to find the best layer composition. The examination construction on a real road is executed by the combination by seven kinds of, and six years have passed at most. Each combination was evaluated from the effect on the durability of the noise decrease function at the present stage, the endurance performance, and the environmental noise decrease. As a result, it came to execute two layer type low noise pavements in full scale in Tokyo.

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In the case of construction of large scale shopping malls and extension of those business hours, consideration on the ambient environment, such as noise issue, is essential. To investigate application of the rubber elastic pay ements, which are expected high noise reduction effect, for the parking of large shopping mall, the measurements both of road vehicle noise and shopping cart noise at low speed were carried out. As a result, it becomes clear that the rubber elastic pavements show high noise reduction of road vehicle noise at low speed and the noise from shop ping carts can also be reduced.

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In this study, in order to predict the plastic deformation of soil-based pavement materials with cyclic loading, a elasto-plastic model based on the modified Cam-Clay model revised by the expanded SMP criterion was developed. And this model was installed in the 3DFEM program called “DynPave3D”. Then the cyclic triaxial compression analysis of granular base material and the cyclic loading simulation of concrete pavement were carried out. As the results, the verification of this model was confirmed from the triaxial compression test analysis, and from the simulation it was found that a void under the concete slab was progressed and the deflection, stress and strain of the concrete slab were increased.

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Three dimensional finite element analysis (FEA) of pavements with thin and ultra thin whitetopping (UTW) is carried out to quantify the bond level between the concrete overlay and the existing pavement. Spring elements are employed at the interface to simulate the bond between the layers. Using appropriate spring stiffness values it is possible to simulate fully bonded, semi-bonded, and un-bonded conditions. A definition of bond level is introduced that is based on the strain gap between the two layers at the interface. Finite element simulations are carried out on the pavement that was tested by the Obayashi Road Research Company. The simulation results are compared with the experimental values and showed the bonded level at test section.

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Porous a sphaltp avemenits generallyu sed for parkingl ots in ServiceA rea of the Japanese expressways.Howiet vsoerm etimessu ffersf romc utbacko f asphalat nds trippinogf aggregates One of the solutionto thesed istresps roblemiss the use of porousc oncretme ix for the surfacec ourse.I n this study pavemensttr ucturues ingp oroucso ncretien parkinlgo ti sf irste xamineadn, dt heni tsm ixd esignu singa rational compactiomne thodb asedo n actuacl onstructiporno ceduriess p robed.F inallyit wasf oundth att argest trength andm ixo f poroucso ncretaep propriaftoer p arkinlgo tg ivesc ostr eductiorna thetrh anc onventionmailx p rocedure for roadways.

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In order to secure an appropriate density by compaction and with necessary properties on a road surface, evaluating quality and managing consistency of RCC for the RCCP are important.
In this study, It is examined the evaluation method of consistency and mixture design method using α and β which are an engineering combination factor.
And we proposed compaction factors of the RCC bottom area depended on the finisherbility and the change of consistency with a passage of time.

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To improve the reliability of pavement life-cycle cost (LCC) calculations, accurate performance curves are necessary. Conventional calculation methods obtain the typical deterioration trends of the road surface from regional data that are widely dispersed. While such methods may be effective for network-level examination, they are not effective for project-level examination: The network-level deterioration trends often differ from the project-level deterioration trends (i. e., the trends at each site). We studied a method of calculating performance curves that considers project-level deterioration trends and dispersion patterns.

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This study proposes policies for the use of type-II modified asphalt mixturc, by assessing the long-term service performance of such pavement and the economic efficiency of using the mixture to extend the pavement lifespan.
Based on data from a trackin g survey, quantitative assessment of long-term service performance has confirmed that modified asphalt mixture extends the period between repairs and the pavement lifespan. Furthermore, life-cycle cost analysis for a 40-year service life revealed that use of such mixture affords cost reductions for road administrators and road users.

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Porous asphalt pavement has been constructed expecting a water permeability function and a low noise function. But it is a problem that these functions fall in a few years. In this paper, it is reported the result of functional recovery tests and the result of examination what best frequency of functional recovery works is in the view of cost performance which is based on the data of the practical road in Japan. It was clarified that we may be able to set the best frequency, in the view of cost performance, of functional recovery works by considering the water permeability and MCI.

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In proportion to increasing porous pavements, demand and application of high viscous polymer modified asphalt grows, and quality management and evaluation becomes more important in the ordering system based on performance-related specifications. However, dispersing morphology and qualitative characteristics in manufacture and storage of this compound material which is thermo-plastic elastomer melted with heat in asphalt, is yet to be clarified, while more reliable guarantee on its quality is required. So far we have been studying evaluation methods of the characteristics of this material during manufacturing process, using indoor pilot equipment made similar to the real factory equipment Hereby, we examined material separation during storage after shipment from manufacturer's tank to the users such as asphalt mixture plants, which constitutes a primary issue in considering quality guarantee.

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Aggregate pop-out is one of the major damages of porous asphalt pavement. As for the causes of pop-out damage, initial performance of modified binders such as shear strength and brittleness at low temperature must be an important factor, but the author focus on the deterioration of modified binders due to ultra-violet rays (UV) in this study. The results of Cantabro-loss after UV irradiation showed that accelerated UV aging induced the aggregate pop-out damage of porous asphalt mixtures. Binder properties after UV irradiation also showed the increase of Fraas Breaking Point and oxygen containing functional group. Furthermore, it was confirmed that there is a good correlation between the increase of oxygen containing functional group and Fraas Breaking Point.

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It has been known that a stiffness of asphalt mixture varies with its temperature. A temperature prediction of asphalt mixture and a relationship between its stiffness and temperature constitute important elements when pavement life span is predicted.
Pavement temperature depends solar radiation, air temperature, wind velocity, infrared radiation, thermal properties of materials constituting pavement. Focusing on the thermal properties, we present the method to estimate thermal properties of materials and discuss the estimates of thermal properties obtained from meteorological data and temperatures measured by thermocouples at our field test site.

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In this research, to establish the method of recycling porous asphalt mixture, the propriety of two mixing design methods being proposed was examined. The result is shown below. 1) The problem was found in the deciding method of the amount of rejuvenators of recycled porous asphalt mixture and the deciding method of optimal asphalt content 2) It has been understood might not obtain satisfactory properties about mixture properties not so examined when mixing is designed. 3) It has been understood that there is a possibility to be improved from present methods by adding easy tests.

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The addition of polymers and by product waste materials to straight asphalt has shown improvement of binder's properties. In this research, the rubber powder by which the waste tire of the passenger motorcar smashed with the freezing-method is added to the straight asphalt 60/80. Rubber 0.2mm, 0.4mm, 0.6mm, 0.8mm and 1.2mm, respectively, was mixed with asphalt at a rate of 15% by total weight. The viscosities measured with a rotation viscometer, Complex Shear Modulus (ΙG^*Ι), phase angle (δ) and softening point temperatures evaluated the behavior at high temperatures. The flexural creep stiffness and slope of response evaluated the behavior at low temperatures. The improvements on binder properties after rubber addition showed the same magnitude despite the difference of rubber size.

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Though the 1.1.1trichloroethane has been chiefly used in the test of extraction of asphalt so far, it was abolished in 1995 because of the consideration of safety to man and the environment. As a result, it is a current state that a substitute solvent of the vegetable or the oil is selected in each organization, and the full automation machine is developed. However, these methods still have some problems about the method of the extraction of the reforming asphalt, dryness, and the waste fluid processing.
Therefore, to solve these problems, we attempted the use of supercritical water to the extraction examination. As a result, it was elucidated that supercritical water had an enough ability to extract asphalt, and to collect a corpuscle material. This suggests being able to use water to test of extraction as a solvent, and we report on these.

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Asset management system has always been an important technical area in the world. The asset management isconcerned with the entire life cycle of transportation decisions including planning, programing, construction, maintenance, and operations. National government and local government would like to develop asset managementsystems in Japan. The application of concept of pavement management system will make it possible for many assetmanagers to do a better job of managing their assets. The developing process of pavement management system in USA will be useful to establish the asset management system in Japan. Performance, historic, policy, geometry, environmental and cost related data are indispensable for pavement and asset management system.

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