Development of airport pavement system that deals with activities from design to rehabilitation successively is summarized, focusing on the current system in Japan. First, as functions required for airport pavements, both riding safety and structural capacity are described in detail; that is, evenness and skid resistance of the pavement surface in the former, and load carrying capacity in the latter. Then, the system of airport pavement design is argued in addition to loading and environmental conditions. The methods to evaluate the pavement conditions on required functions are also discussed. Finally, the rehabilitation strategies in both asphalt and concrete pavements are described.

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Development of a new non-contact profilometer using a laser interferometer has made measurement possible at the normal speed of vehicles and enabled a huge volume of data to be processed rapidly. Employment of the “sequential two point method (STP method)” has made measurement of the profile at intervals of 1mm and with accuracy of ±1.2mm. The new profilometer can be used to analyze even the macrotexture and obtain the profile quite accurately. The acquired data can be used as basic materials for evaluating the geometrical characteristics of pavement and a wide range of approach is now possible to solve various problems.

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Extension of the porous pavement is expected, even in urban expressways, as it serves for not only the traffic safety but also the roadside environment. The porous-pavement-mixture with a high-viscosity-modified-asphalt binder resists flow better than the conventional asphalt mixtures, but on bridge-decks, adhesion of binders may fail owing to the penetration of water. In this study, immersion wheel-tracking tests and bond-strength tests of different porous-pavement-structures and mechanical properties tests of base materials were carried out. From the results, it was found that there is a correlations between the resistance against stripping-failure and the bond-strength, and the bond-strength is influenced by the mechanical properties of base materials.

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For a connection between two concrete-filled cirailar steel pipes, a simple sleeve joint in which a smaller diameter pipe is inserted by the specific length to a larger diameter pipe with a concrete or mortar annulus filling the gap between them has been proposed as an economical and effective joint system. In the present paper, the load-carrying capacities and failure mechanisms of the present joint system are experimentally investigated. The experiments indicate that the ultimate and yield strength increase proportionally with the increase of the overlap length and the wall thickness of pile pipes. In addition, a method to predict ultimate strength of the present joints has been proposed.

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Longitudinal profile measurements are carried out on an actual runway of a principal airport near Osaka in Japan, using a newly developed non-contact type profilometer, being combined with Global Positioning System (GPS). It is capable of acquiring a profile of the pavement surface at intervals of 10 [mm] with accuracy of ±1.2 [mm] at normal vehicle speed.
Characteristics of the runway profiles are presented, and a computer simulation of a large sized aircraft has been employed to simulate a taking off motion of an aircraft to evaluate the aircraft's comfort, influence on the crew, on the body of the aircraft, on the pavement, etc.

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The most important failure form in buried joint is transverse cracking. Long term serviceability deeply depends on the cracking resistance of joint layer. To decrease effects of bridge deck movement, the grid panel type has not only debonding part between asphalt layer and concrete slab but also honeycomb grid panel in the binder course. The layer reinforcement is indispensable in this kind of buried joint, since stress is easy to relax in a low stiffness state of asphalt mixture. In this paper, it was quantitatively evaluated that layer stiffness increases by embedding the grid panel into asphalt layer. Based on the field measurement, actual rate of strain induced in the buried joint was investigated. Direct tensile tests were carried out to plain mixture specimens and mixture-grid panel composite specimens. From the test results, relaxation modulus of low stiffness condition was estimated by applying the time-temperature superposition principle, and reinforcement effect of grid panel was evaluated.

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The influence of water to cement ratio on the corrosion mechanism of steel bars embedded near a bending crack was experimentally investigated. First, early corrosion tests were syudied using mortar. Chloride ion and oxygen permeations were investigated, considering the gap between steel and concrete. The influences of those permeations on macrocell corrosion were studied. Lastly, tests on concrete specimens were conducted to confirm the results obtained from the mortar cese. Results show that the permeation near the bending crack plays a important role in corrosion behavior.

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The new method to determine the tension softening curve of concrete has been proposed in this study. To solve the problems included in the modified J-integral based method, the release of an elastic energy has been considered quantitatively based on the unloading and reloading experiment of notched beams subjected to a concentrated load. In addition, based on the measurement for the distribution of fictitious crack width of a notched beam, the propagation of the fictitious crack has been evaluated quantitatively. The new method in which these new findings are incorporated has been applied to estimate the tension softening curve of various concretes and the validity of this method has been confirmed experimentally.

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In this study, AE signals due to cracks occurring dominantly in reinforced concrete (RC) beams was characterized by AE waveform parameters through the model tests for bending cracks, shearing cracks and bond cracks between reinforcing steel bars and concrete. Then in order to verify the validity of the results for these model tests, AE measurement was performed during the bending test for the RC beams. Finally, the loading to the existing RC beams of the in-service aging dock was carried out by moving the dump track on the beams so that the applicability of AE technique to the evaluation of the deterioration of RC beams subjected to flexural loading was examined.

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A simplified testing method is herein proposed for the engineers working at sites. Various testing machines for the adiabatic temperature rise have been developed before, however these machines are complicated and expensive to use at the site. Furthermore the machine has not standardized in the societies. The apparatus developed herein consists of a simple Styrofoam box and a temperature measurement apparatus. The adiabatic temperature rise is calculated by summing the rising temperature in the box and the temperature losing to outside, which provides fairy good agreement compared with the previous test data.

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The design method of pull-out shear capacity of footing supported by four piles is shown in Standard Specification for Concrete of JSCE. However, since the specimen used for verification is generally limited to small models, the size effect on pull-out shear has not been evaluated quantitatively enough. Furthermore, the contribution of shear reinforcing bars (stirrups) to shear capacity is not also clarified enough. Therefore, in this study, pull-out tests using full scale specimens are newly carried out in addition to our previous experiments. Through these test results, we evaluate the design method of pull-out shear capacity taking account of size effect and contribution of stirrups. In addition, based on the behavior of embedded steel member as anchorage obtained from detailed measurements, we try to rationalize the design method of the steel anchor.

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A caisson type foundation is generally used for power hansmission towers in mountainous areas. The leg of the tower, which is a steel pipe with ribs is embedded in the cylindrical concrete body as an anchor. Some experiments have been conducted by pulling the anchor for analyzing the failure mode and ultimate capacity. In this paper, experiments are carried out by choosing diameter, anchor length and concrete strength as test parameters. Tharefore, two dimensional plane stress finite element analysis considering splitting cracks based on fracture mechanics is carried out in order to investigate fracture mechanism.

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A caisson type foundation is generally used for power transmission towers in mountainous areas. The leg of the tower, which is a steel pipe with ribs, is embedded in the cylindrical concrete structure as an anchor. Some experiments have been conducted by pulling out the anchor for investigating the failure mode and ultimate capacity. It was found that the failure mode was the splitting failure with cracks propagating from the pipe rib.
This paper describes the simulation of the behavior of the concrete cylinder with pullout anchors. It is impossible to simulate splitting cracks by a pure axial symmetric geometry. Therefore, a quasi 3-dimensional analysis using an axial symmetric geometry with the smeared crack element and the non-linear constitutive model in the circumferential direction based on fracture mechanics is carried out. The results of the simulations show the same failure mode and load-displacement relationship compared with experimental results. Some real size foundations, having a diameter of three meters, are also computed by the same numerical method. From the results of the analysis, it is found that the bearing capacity has a size effect.

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The aim of this study is to invesigate the minimum reinforcement requirements for PRC (Prestressed Reinforced Concrete) beams subjected to bending moment and shear. Based on the ultimate limit state design procedure by “Standard Specification for Design of Concrete Structures” of JSCE, the minimum reinforcement requirements have been analytically examined and quantified by using the parameter of concrete strength and the level of prestressing. Furthermore, compared with the foreign design specificaions and the Standard Specification of JSCE, the concept of the minimum reinforcement requirements for PRC beams subjected to bending moment and shear have been mentioned.

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Approximate formulas for calculating the pavement slab deflections on both Winkler and elastic solid subgrades are presented on the basis of thin elastic slab theory. The back-calculation process for estimating pavement structural parameters can be implemented by adopting these formulas. The validity of the procedures proposed in this paper was demonstrated by examples. The subgrade idealization influences the result of back-calculations; that is, the elastic modulus of pavement slab back-calculated in the Winkler subgrade idealization case was higher than that in the elastic solid subgrade idealization case for the same deflection basin.

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