In the testing manual of the road surface hardness test, the desirable range of the test result that a walker can pass by security comfortably is shown. However, it is difficult to use the test results for the structure design of the pavement for walkers directly. The subcommittee on pavements for walkers, the committee on pavement engineering, JSCE carried out the road surface hardness test and the portable FWD test at various sidewalk pavement in the site of the Togashira public apartment and Tokyo University of Agriculture, and the same subcommittee carried out questionary survey in the Togashira public apartment. In this study, from those results, a pavement design method for walkers in consideration of comfort and safety was examined. As a result, it was found that the surface modulus crrespondig to the desirable range of the road surface hardness test result was 30~120 MPa, and that it was possible for a structure design by the elastic theory with the surface modulus.

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 Airport pavement design manual in Japan was revised in July, 2008. In this revision, empirical-mechanistic design method was introduced as one of standard design method. It is possible to design airport pavement thickness theoretically by using this design method. However, there is not enough case yet. Therefore, the effects of design values used for empirical-mechanistic design method such as traffic conditions and material conditions on pavement thickness are verified. Furthermore, pavement thicknesses designed by empirical method and empirical-mechanistic method were compared.

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 Hokkaido's standards are specific to cold snowy regions, and differ from those employed in temperate areas. It is known that the strength of pavement is affected by freezing in midwinter and by thawing in spring, as well as by other environmental conditions. Accordingly, it is necessary to duly consider environmental effects in addition to the influence of materials in mechanistic-empirical pavement design (MEPDG) in cold snowy regions. This paper reports on a study of materials and environmental conditions to be used in MEPDG in such regions based on findings from surveys conducted on test roads and the outcomes of laboratory experiments. The study results indicated a need to consider elastic moduli in relation to freezing and thawing when MEPDG based on multilayer elastic theory is applied to cold snowy regions. A method involving the setting of an elastic modulus for each pavement layer was also proposed in the study.

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 The aim of this study is to verify the applicability of using falling weight deflectometer(FWD) time history data to evaluate fatigue damage of asphalt pavements. The applicability of the analysis technique was verified through dissipated work which was caluculated from FWD time history data. The data analyzed were obtained from tests conducted on eight test sections for about fourteen years. The results showed that FWD dissipated work can be used to evaluate the road fatigue damege.

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 This paper presents an improvement framework on accuracy for the evaluation of stiffness of unbound aggregates using portable FWD(PFWD) by Shakedown theory. According to the theory, the unbound aggregates is liable to show almost no progressive accumulation of permanent strains under repeated loading if the magnitude of the applied loads does not exceed a limiting value, called the Shakedown load. The growth of permanent was shown to level off by the 10 cycle load applications at the same strain level using PFWD and a conventional triaxial compression test. Therefore, this PFWD loading test is said to have attained a state of Shakedown. By visualization method, the photos taken at the cross section of small earth tank before and after loading by PFWD were revealed the upward displacements of soil particle on the surface.

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 Last year, positive bending test used asphalt mixture and steel composition specimens was performed by dynamic loading. In the study, it was found that there were many cases tensile strain occurred in asphalt pavement though asphalt mixture was deformed to positive bend. So, in this study, viscoelastic analysis was performed. As a result, it was able to be found tensile strain similar to experiments was occurred. And it was able to be reproduced strain behavior of asphalt mixture that was not able to be reproduce d by liner elastic analysis. In this study, it was able to be confirmed that viscoelastic theory was necessary to understand strain behavior of asphalt pavement on steel deck plate.

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 It was determined how to evaluate pavement surface condition such as roughness and a bump with acceleration measured on a vehicle axle. First, we measured acceleration on a vehicle axle at some levels of vehicle speed to determine the relation between the acceleration and the speed, from which the equation for standardizing the acceleration with the speed was established. Next, for the evaluation of pavement surface unevenness in a project level, the correlation was made between the standard deviation and IRI at every 20 m long section. The pavement surface unevenness could be reasonably evaluated according to the relation. Also, an amount of a bump was able to be estimated quantitatively from the peak value of acceleration and the speed. Furthermore, in a network level, the method was developed to evaluate the pavement surface unevenness of different types of road in the same index.

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 Faulting of pavement surface such as manholes and construction joint and pot hole will be source of vibration and noise. Faulting of surface of bridge deck pavement are also said to cause damage of RC slabs. To evaluate faulting of pavement surface of three elements of traveled surface characteristics is difficult. In this study, faulting of pavement surface measuring vehicle was developed to quantitatively assess the faulting of pavement surface by measuring the acceleration of the wheel axle receiving a faulting of pavement surface when passing through a vehicle. Using this measurement vehicle, revealed the threshold value of the faulting of pavement surface cause an evaluation of vibration hazard sources in the pavement surface. With respect to the bridge surface pavement, set of management indicators for setting priorities focused on the road surface repairs near the expansion joint.

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 This study examines an evaluation method of road surface roughness with consideration of ageing characteristics by discrete wavelet transform. First, a multiple regression analysis showed that the spatial frequency subbands related with wavelengths of 2.4-4.8m and 1.2-2.4m correspond with aging characteristics of surface roughness. According to the results, we proposed a detection method of the roughness aging characteristics in a profile. The detecting results contribute to identify the profile segments that require the repair of a pavement surface. Finally, wavelet-based profile analysis confirmed that the repair of local profile segments corresponding to the roughness aging characteristics improves the performance of smoothness of the entire section in the road surface evaluation.

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 In general, "Vertical Vibration of passing vehicles" (induced by road profile) influences dynamic load of the vehicles. We assumed that the structural damage of the pavement was predictable if the relationships between a road profile and a dynamic load could be clear. To verify this assumption, we conducted several experiments. First of all, the method of calculating a dynamic load from the road profile was examined. Next, according to this result, the influence of the road profile and the transport speed of passing vehicles on a dynamic load was theoretically analyzed. Finally, the relationships between the structural damage of the pavement affected by the dynamic load and the road profile was examined associated with LTTP data. Based on these studies, it was confirmed that high correlation between "Modifying Coefficient of Dynamic Load" (developed as an evaluation index of the dynamic load) and the pavement deflection measured by the FWD. In this paper, it was concluded that the structural damage of the pavement could be simply obtained by the road profile data.

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 In the general road in recent years, the sediment pavement attracts attention as pavement which considered environment. On the other hand, many sediment pavement in which the road surface was formed with gravel etc. as non-pavement. Performance specification for pavement structure design of road was established by MLIT in 2001, and also performance specification for pavement structure design of farm road was established by MAFF in 2005. In this research, the longitudinal surface profile on existing sediment pavement or general asphalt pavement was measured and analyzed. And, the sediment pavement had the road surface characteristics, such as having comparatively big irregularity at the short interval.

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 In our existing researches, relationships between the skid resistance and the bare pavement ratio have been clarified, in order to establish the handy and qualitative evaluation method of the skid resistance on freezing pavements. From the viewpoint of the field adaptability of laboratory test results, the field tests were carried out in Rout 230, to require measured skid resistance data and the calculated bare pavement ratio based on image analyses of in-situ freezing pavement images. As results of comparison study, there were found out to be some agreement on dense graded pavements surfaced with the compacted snow, and also the effects of pavement temperature on the skid resistance property in this research.

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 In the mechanical design method of asphalt pavements, it is often examined that the elastic modulus of the subgrade material is determined by using a simple calculation equation "10*CBR" which was adopted for the Shell's design method. However, from the results of domestic and foreign findings, it was unidentified that the simple equation "10*CBR" has how much reliability, because the elastic modulus was distributed widely from "5*CBR" line to "20*CBR" line, even if it was the same CBR value. Therefore, in this study, by using the rearranged past data, the reliability of the subgrade elastic modulus was examined when the design CBR was applied to the simple equation. As a result, it was found that the reliability of the simple equation "10*CBR" decreases with increase of the degree of reliability. Hence, a new simple equation using the exponential function for calculating the subgrade elastic modulus, which can set coefficients depending on degree of reliability, was proposed in this study.

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 In concrete pavements, subbase and subgrade are required to provide uniform support for concrete slabs. However, permanent deformation at the top surface of subbase due to plastic strains in granular and soil materials causes loss of the support. The aim of this study is to develop a method for predicting the plastic strains in subgrade and subbase. The VESYS model that describes the plastic strain as a function of the number of load repetitions and elastic strain is employed in this study. The model was incorporated into a 3 dimensional finite element program, Pave3D. Validity of the model was verified from a simulation of results of repeated loading test on a test pavement. Also, the effects of the permanent deformation on the stress and deflection of concrete slab were examined.

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 This paper examines the effects of freezing and thawing on the mechanical behavior of granular base under unsaturated condition through the long-term field measurement of ground temperature, water content and deformation inside pavement, by performing FWD tests before and after freeze-thawing and by developing a new CBR test of freeze-thawed base course materials. We also evaluate the influences of the change in the stiffness of granular base due to freeze-thawing on the fatigue breaking of pavements in cold regions by applying the theoretical design method for asphalt pavement in consideration of the effects found in this paper. As the result, it was revealed that the freeze-thawing of granular base has a strong influence on the fatigue life of pavement structure in cold regions because it varies the deformation-strength characteristics of base course materials.

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 Recently, concrete waste materials decrease main application as base course recycling material (RC-40) and are in a surplus tendency around an urban region, and further applications are required from the viewpoint of recycling promotion. Therefore, we used RC-40 as aggregate of the cement asphalt emulsion stabilization (CAE) mixture, and further aimed to improve the quality and stability of the mixture produced by a central plant mixing system. In this study, we conducted test construction CAE mixture which varied the amount of added cement and asphalt emulsion, estimated the elastic modulus by FWD measurement, and clarified their temperature dependence. As a result, the cross section of pavement design using a CAE mixture confirmed that it is more reasonable to apply a theoretical design method than the conventional T_A methods.

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 The purpose of this work is to investigate the difference of bearing capacity of granular base courses which have different grading curves in the range of quality standard. In this work, we used new material and recycled materials produced from cement concrete, asphalt concrete or roof tiles. The CBR value was compared among specimens of a fix material but with a different grading curve which was prepared artificially. The grading curve which gave the maximum CBR value was identical for all the materials. It should be noted that the CBR value of the maximum is more than two times as large as the minimum. So it was found that the artificial grain size preparation improves bearing capacity of granular base courses if the grading curve is not appropriate. We can approximate the grading curve which results maximum bearing capacity by setting n value equal to 0.4 - 0.5 in Talbot's equation.

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 This study is to evaluate whether or not a highly concentrated modified emulsion or a specially modified asphalt will prevent porous asphalt surface layer's underlying binder layer from getting deteriorated. Judging from full-scale accelerated pavement testing, both of the materials can be more preventive to the binder layer's segregation than conventional emulsions, in case there is no defect in the original binder layer. If the original binder layer is a lready defected, however, the layer tends to be further defected due to repeated traffic loads, although the two materials can retard the distress at early traffic stages. Based on these results, applicability of the materials in the field are to be considered.

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 Grout materials are sometimes injected beneath airport PC slabs in order to compensate the ground settlement. However, parts of them are pulverized by repeated aircraft loadings, which results in reducing aircraft running safety. In order to improve the resistance to pulverization, the authors developed a new grout material, a mixture of the grout material currently used in airports and organic fiber. Then a series of model tests was conducted to examine the durability. Based on the results of the tests, the durability of the new grout material was improved in comparison to the conventional material although the workability was maintained.

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 On runway pavements, grooves for transverse directions should be set on most of runway area. To investigate of the stability of the runway grooving against heavy duty aircraft load, wheel tracking tests were conducted. The tests were conducted on four materials under the same tire pressure as that of the real aircraft (A-380). As a result of the tests, (1) the effect of curing period is small when the large aircraft load is suffered. (2) The extent of grooving damage was improved by using modified asphalts compared to straight asphalt. (3) The stability of grooving was improved by loading of the aircraft before setting grooving. Moreover, we suggest the evaluation technique of the stability of grooving, by means of the relationships between reductions of the groove and rutting.

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 In order to evaluate runoff control proper ties of three types of permeable pavements, namely, porous asphalt pavement, permeable interlocking concrete pavement and water-holding interlocking concrete pavement, experimentally obtaining permeability and water retentivity of each pavement material, this study conducted rainfall-runoff simulation of the three pavements using UNSA-2D, an numerical analysis program of saturated-unsaturated seepage flow. The input parameters of the numerical simulation were determined by fitting van Genuchten (VG) model or Irmay model into the experimental results. The simulation was performed under constant rainfall condition of three rainfall intensities and varying rainfall condition of center-peaked pattern. The results of numerical simulation revealed runoff characteristics of the three pavements, such as the temporal change in storage and infiltration with time, the runoff beginning time depending on the rainfall intensity and so on.

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 Relative compaction, gradation and bitumen content have been shown as inspection terms on "Pavement design and construction guideline" authorized by Japan Road Association(JRA). Extraction test has also been indicated as the standard test of bitumen content on "Pavement surveying and testing handbook" by JRA. However, this test has some problems such as taking time and too underestimates of fine aggregate. From the viewpoint of the effective quality evaluation, the aim of this study is to suggest CT value as a new quality evaluation index using X-ray CT scanner. After the CT scanning for the specimens of the dense-graded asphalt mixture, CT values are computed and values shown as below were also calculated; 3 threshold values to divide into void, bitumen with filler, fine aggregate and course aggregate, section average CT value, and average CT values of each component. Therefore, X-ray CT test has possibility of evaluating quality of asphalt mixture effectively and exactly.

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 The estimation of thermal properties is described with simulation data and the measured temperatures by a several thermocouples buried in the pavement test section. AIso, the validity of the theory is verified by the simulation data, and the influence for numerical calculation caused by the measurement errors of thermocouples and the buried position of information for thermocouples are examined. It was found that the measurement data including these errors affects the accuracy of therrnal properties estimation. The error of buried position especially affects the numerical results. Next, the thermal properties were estimated by the measured temperature at the pavement test section, and it was confirmed that the number of layers, thermocouples and locations affected the result of estimating thermal properties. If there are errors on buried position of thermocouples in the test section, thermal properties can be estimated by correcting the position infbrmation of buried thermocouples.

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 In standard specifications for pavements(2007), the performance design method for pavement was introduced, and performance like bearing capacity, safety, comfortability, environmental load reduction and their verification methods was described. For safety performance, joint faulting must be verified based on the presumptive joint faulting value calculated by the estimating equation of joint faulting data which was originated in the USA. The applicability of estimating equation was studied by using data of Japanese expressways. As the result, both accumulated erosion amount and annual precipitation in the equation was not suitable to apply to Japanese rigid pavements. The revised equation was proposed to improve the accuracy of presumptive faulting value.

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