To scale up the traditional clay coal kilns as they are for the purpose of carbonizing voluminous driftwoods in reservoirs can be questionable from the viewpoints of the structural stability and durability, because of taking place of cracks, exfoliation and deteriorations caused by high heat expansion and its shrinkage through cyclic heat process. In the paper, numerical studies as to heat transfer, stressstrain and deformation behaviors during carbonization process using a large scale kiln model will be examined in order to refer to the problems and their solutions on the design antecedently. Finally, the large scale OKUTADAMI kiln applied above lessons learnt is constructed and operated satisfactorily

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Tokyo international Airport Offshore Development Project has been carried out on super soft ground composed of waste disposal field. There were many technical limitation under which ground improvement is performed. Airport foundation was formed by various kinds of invention in design and construction. This report outlines three features as follows: outstanding subjects on foundation engineering in airport construction on super soft ground, design and construction of ground improvement in the third stage zone under the most difficult environment in construction, the actual effect of ground improvement shown by proposed observation-construction management system.

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Although tide level observations are important for surveying tide behavior and marine construction, it is still difficult to obtain these observations in the area where tide flows rapidly and changes occur suddenly. Authors propose an application of the GPS (Grobal Positioning System) to tide level observations and an equipment for detecting ship oscillation.
The results of field experiments show the method proposed here is applicable for tide level observations. Furthermore, the laboratory and field tests show the equipment developed in this research is effective to detect and compensate the short period oscillation of ships in the case of offshore observation.

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Osaka Nanko Tunnel is being built using immersed-tube elements. The elements are composite structures of steel and concrete, the concrete of which is classifiable as mass concrete, as it is more than 1m thick. Consequently there was concern that thermal stresses occurring during fabrication could lead to cracking in the concrete. This paper deals with the results obtained from the measurement of thermal stress. The ratio of restriction was calculated using measured values, and, by means of comparisons with existing measured data and data published by American Concrete Institute, the determination of the ratio of restriction in steel-concrete composite structures was studied.

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The real-time GPS (Grobal Positioning System) marine surveying system has been completed in this research. In order to improve the applicability of the system, the following two items are adopted: (1) a new wireless transmission apparatus; and (2) the dual frequency OTF (On The Fly) calibration method.
To verify the system, the field investigation was conducted around the Kanmon strait area.
Results showed that the system developed here is available for a range (35-40km) twice the size of the former system. The reliability of wireless data transmission and OTF calibration was also improved.

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Diaphragm wall foundation is one-wall type foundation of rectangular section without pile cap, and appropriate for neighboring construction because of littleness of excavation volume. Authors have conducted a series of loading tests using full-scale models (vertical: 2, horizontal: 4) for the purpose of establishing reasonable design method on this new type foundation at the site for Dai-ni Tokai Highway viaducts. This paper describes not only the end bearing capacity and skin friction of this foundation based on the results of vertical loading tests but also the useful information on lateral loading capacity of this method obtained from comparing experimental results with the corresponding simulation analyses.

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We experiment on eco-mixed seeding, combined with seeding of native species and cutting of salix spp., which was devised from the reseach of restoration procsses of natural forest stands on riparian zones and volcanoes for restoration of natural forests. Judging from the first stage of the experiments on levees and major beds, this method is suitable for restoration of natural forests, and we propose that the cultured seedling groups by one pot and the macadam mulch should be combined with this method to introduce more native species.

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The study is made with the prime object of determining the project management systems appropriate to Japanese companies when carrying out internationl projects. In order to decide upon effective management methods and for the purpose of clarifying the essential diffrence in basic concepts, as between own country's ways and those of others, it is necessary, first cultural anthropology and sotiology in respective countries. With such due considerations, this study analyses how Japanesse management characteristic, which are firmlyrooted in processes and sociohuman characteristic of Japanese people, affect execution of internationl projects.

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This paper involves a small scale experiment in laboratory of the lime mixing process, and an in-situ cleanup execution by DJM (Dry Jet Mixing) method with lime for contamined cohesive soil with VOCs.
Temperature of the improved subsoil rose to about 80°C by mixing with 100-150kg of lime per m³ of cohesive soil, and the recovery rate of contaminants came to more than 95% within two cycles of penetration-withdrawing path of mixing blade, and none of residual content were able to exceed the environmental quality standard.

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Many landslides have occurred at the fault zone near Meadian Techtonic Line by the construction of the expressway. MTL is the first class fault in Japan and have a big fractured zone. The mechanical characteristics and countermeasures of landslides occurred at the fractured zone on MTL ware discussed. It was cleared that the angle of shear resistance φ′ of clays at the fractured zone was relatively small, about 20°-35°, and the fall from φ′ to φ_r was notable, about 15°. This small angle of shear resistance is one of the main causes that the countermeasure of landslide on MTL is generally difficult. The countermeasure of Kuino landslide on MTL was designed carefully.

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An equation for the S-N curve is proposed from the test data obtained in the present study. This equation was determined from the rerationship between the applied stress S and the failure stress repetition numbers N, which are assumed to be disributed in a logalithmic normal function. The equation provides rather lower strength compared with the equations for pavement concrete and RCC.
Relationships of life probability P and the S-N curve were determined based on the McCall and Weibull distributions, where life probability of fatigue strength at 2 million repetitions was determined. From these results the applicability of the recycled aggregate to the RCC is also investigated.

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In the construction of a tunnel in which the depth of overburden reaches as much as 900m, noticeable support deformation began to occur after the depth of overburden exceeds 400m. Because even greater deformation was predicted if the standard support pattern were to be used, special support patterns which include the use of high-strength shotcrete were introduced. In the introduction of these support, Pi-Δr curves were sought through back analysis and elasto-plastic analysis using measured data, displacement and support pressure were computed for various depth of overburden, and the corresponding support were determined.

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Displacement measurements and monitoring have a important role in design, assessment and control of ground structures as well as in the mitigation of ground disaster. The authors have developed a real-time monitoring system for ground displacement measurements by using the Global Positioning System.
This paper describes the detailed configuration of the system hardware and software. The results of the field experiments, performed to investigate the measurement accuracy of the system, are also shown. The system developed here will be useful for continuous displacement measurements of the ground over an extensive area.

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The purpose of this study is to develop the new algorithm on the land use capability classification applying the Analytic Hierarchy Process (AHP) method. In the land use capability classification model developed by ourselves in 1990, not only geographical information but also satellite data could be used. In this study, through the AHP method using the plural land use capability classification maps as the evaluation parameters, the algorithm to make the two kinds of the land use conception maps, which is called “the development type” and “the preservation type” respectively, was proposed. Furthermore, from both conception maps, “the mutual regulation map” considering the balance of development and preservation was newly drawn up based on the weight for the evaluation parameters calculated by the AHP method. This mutual reguration map is very useful for supporting the decision making for the future land use plan and planning.

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A soft roadbed causes an increment of existing track maintenance work. Therefore the chemically stabilized method is often adopted for improvement of existing railway roadbed in order to lighten the burden on track maintenance work. Thus, it is necessary to investigate the durability of chemically stabilized soil under repeated train load. The present paper gives an outline of the static and cyclic loading tests for investigating the basic characteristic and durability under repeated load of chemically stabilized soil. The result from cyclic loading test shows that the strength of chemically stabilized soil has to be more than 5 times the cyclic stress in order to keep durability of chemically stabilized soil under train load.

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This paper presents the research results of water sealing mechanism concerning cutting face stable mechanism of earth pressure balanced shield subject to high water pressure.
The study was conducted through theoretical and experimental test on model emphasising on water pressure drop in screw conveyor while mucking of earth excavation. In the theoretical study, high water pressure was considered in theoretical formula, then proposal for probable discriminants of stable mucking has been made. In the experimental study, verification of this theoretical formula has been done. The results of experimental test and theoretical analysis recognized good agreement.

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In order to investigate utilization of fly ash and flue gas desulfurization wastes for road base under light traffic, authors performed various laboratory tests. Futheremore, we conducted test pavements at three existing roads (L, A-traffic) for field observations investigating bearing capacity, strength and condition of road surface after construction.
The results obtained from laboratory tests and field observations showed that mono-layer base constructed with mixed materials using fly ash and flue gas desulfurization wastes had sufficient durability against repeated load and, in addition, could transfer sufficiently traffic load to subgrade.

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