In the present study, two styles of ancient tombs, namely, Fun-kyu tomb located in Japan and Tu-Dun tomb in China were introduced first from the archaeological and cultural point of view. They are important historical patrimonies and it is archaeologically inferred that the style of Fun-kyu tomb originated from that of Tu-Dun tomb. In order to make clear the geotechnical properties and the construction methods of these man-made earthworks, geotechnical in situ investigations and laboratory tests were conducted on Yoshinogari Fun-kyu tomb in Japan and four Tu-Dun tombs in China during the two periods of 1993 and 2000-2001. The results of these investigations and tests will be introduced and discussed here.

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To investigate the seismic behavior and the earthquake resistant design methods of shield tunnel with secondary lining in transverse direction, a series of model shaking table tests and two kinds of analyses on the tests are carried out. The investigation concerns with the vibration characteristics of tunnel with secondary lining and ground, the interaction effects between ground and tunnel, the effect of secondary lining and the validity of analitical model of tunnel. In tests, the different structual characteristics of tunnel from the effests of transverse and circumferential joints and secondary lining were focused. In analyses, the seismic deformation method based on beam-spring model and the 2-D FEM dynamic analysis are adopted.

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This paper proposes a valuable road hazard map against falls and failures of discontinuous rock slopes from the practical engineering viewpoint, which makes it possible not only to evaluate risk of rock block fallings and slidings but also to predict the arrival length along a falling path of dangerous rock slope. This road hazard map may be obtained from the simulation analyses of Distinct Element Method based on some useful parameters determined from the proof tests of actual rock block fallings. This proposed map is effective to comprehensively consider the degree of road safety against fallings and failures of rock blocks. Therefore, it becomes easy from it to decide both the preferential construction positions of protected structures as the hard measure aspect and the needful sections of road traffic control as the soft measure aspect.

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This paper proposes an easy method for calculating the contact pressure distribution in the bottom of foundations in order to facilitate optimum design of foundations used in all types of civil and building structures. The foundations in question have horizontal symmetry about the central axis and have a shape made up of rectangular combinations. Existing methods require the repetition of complex calculations, but with the method presented here, the contact pressure distribution can be calculated easily, even for quite complex shapes.

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Lu values obtained by Lugeon test are liable to be underestimated in open jointed rock. In this paper, we try to clarify the analytical relations between the injection pressure and the flow rate in the parallel smooth model and verify the relation experimentally. Finally we confirm applicability of the newly defined flow laws considering turbulent flow in order to evaluate the relation between Lu values and permeability, which is obtained by the viscous fluid in the Lugeon test, in the actual open jointed rocks.

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Rigid Plastic Finite Element Method (RPFEM) for reinforced soil structure was developed and reinforcing soil effects were analytically examined The developed method can consider not only effects of soil properties such as shear strength depending on confining stress or dilatancy but also effects of reinforcing material strength ma series of the numerical examination, the effects of tensile strength of reinforcing material were especially investigated and results by the developed method were compared with the result by RPFEM incorporating constrain condition of no change length by reinforcements. In this paper, outline of numerical method is explained and the numerical examination results are shown.

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In consideration of allowable limit of displacement and deformation associated with rock tunnelling, we should pay more attention to the meaning of the shear behavior of rock joints under constant dilatancy. By employing about 250 specimens which were made of three materials and reproduced from several natural joints with different roughnesses, the authors have carried out direct shear tests under constant dilatancies. The breakage of joint asperity was discussed from the point of view standing on the relationship between shear strength and the loss of asperity. The method to estimate the volume of fractured asperities was proposed and the correlation between shear strength and the volume was discussed. Finally, the authors proposed the new relational expression between the volume of fractured asperities and the shear strength.

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In this study, traffic vibration decrement properties are confirmed by comparing to some different road pavements using the impact vibration generator. The pavements that were compared can roughly be classified into two groups. One of them, the granular materials was applied to subbase, and the other of them, the lime series stabilization was applied to subbase. The comparing tests were carried out with that the vibration level and road surface displacement were measured on these roads surface. In the results, following factors were confirmed. The vibration decrement with the distances was performed with the pavement that was constructed by granular materials to the subbase. And, the generated vibrations were decreased with the pavement that was constructed with lime series stabilization.

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In order to clarify bearing capacity-lateral deformation behavior under various loading and deposition conditions, a series of model tests was performed. The results obtained were as follows; (1) the strength variation of ground attributed to the difference in anisotropy can be estimated by the angle of bedding plane to the maximum principal stress despite of the difference between central and eccentric loadings, (2) the fabric anisotropy affects considerably on cyclic lateral deformation behavior, and (3) the failure envelope depicted in M-V plane may be used to evaluate the stability of structure with any ground fabric conditions. In this paper, mechanism of bearing capacity was also discussed based on the lateral deformation behavior.

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Verification analyses of shaking table tests were carried out. These aimed at resonance that occurred according to advance of liquefaction. Consequently, a simplified dynamic analysis method has be proposed for prediction of complicated behavior of foundation in company with change of natural frequency considering additional inertia force of liquefaction ground is considered. And good approximation of bending moment of foundation can be achieved by considering additional inertia force of liquefaction ground.

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The authors performed a series of drained triaxial compression tests and drained hollow cylinder torsional shear tests for investigating the yielding behavior of a saturated and reconstituted clay sample after experiencing isotropic and anisotropic preloading and subsequent unloading histories. The results indicated that the yieldings after experiencing both preloading histories could satisfactorily be interpreted in an integrated manner by assuming the bounding surface separating the state of elastic response and the state of elasto-plastic response in the space where the effective mean stress, principal stress difference and areal strain were selected as the independent co-ordinate axes.

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This paper describes the results of shaking table model tests and FEM analyses of a slope with anchorage in order to verify the earthquake-proof effect of a coned disk spring on the anchor head. The model tests were carried out for the slope with and without a coned disk spring on the anchor head. The following conclusions were obtained. 1) The tensile force of the ground anchorage changes greatly with the shaking motions. 2) A coned disk spring on an anchor head greatly decreased the tensile force amplitudes during the shaking tests and also improved the earthquake resistance of the anchorage. In the tests, the tensile force amplitudes with a coned disk spring were one quarter to two thirds of the tensile force amplitude without a coned disk spring.

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Recently, mountain tunneling method has been adopted in tunneling under worse geological conditions. In order to stabilize the face and control the ground surface settlement, a variety of supplementary construction methods have been presented, while their design criteria not steadily developed. In this paper, first of all, theory of cylindrical shell was proposed as the rational design method. Furethermore, its rationality was verified and its applicability to actual design was investigated by centrifuge model tests, cylindrical loading tests and measurement data in actual tunneling construction.

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Mechanical behavior of dams is classified into two categories: the static behavior and dynamic behavior. In this study, deformation observed during the period of dam construction and reservoir ponding of 5 rockfill dams is investigated. General characteristics and individual characteristics of the observed deformation are delineated in this paper. The authors believe that the present investigation could provide useful information to dam design methed and sophisticated analyses of dam body behavior.

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It is important to establish an effective evaluation method of tunnel lining deformation behavior caused by adjacent construction such as embankment above the tunnel.
In view of such a situation, we carried out parametric studies using 2-D nonlinear FEM program “NATMFEM”. Parameters of the study areas follows: 1) width of the embankment, 2) Overburden of the tunnel before construction of the embankment, 3) rigidity of the tunnel lining, 4)initial rigidity of the sunounding ground, 5) nonlinear characteristic of the surrounding ground And then, based on these parametric studies, we proposed some nomographs for estimation of height of embankment when lining stress generated by construction of the embankment reaches either bending tensile strength or compressive strength of the lining.

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Monotonic and cyclic shear tests are carried out to study volume change characteristics of gravelly sands. In monotomc tests, the relative density of gravelly sands corresponding the critical void ratio e_cr decreases with the increase of uniformity coefficient Uc, indicating that positive dilatancy is more dominant for gravelly soils with larger Uc. On the other hand, volume reduction of gravelly sands under cyclic loading, which is almost independent of Uc, depends greatly on whether initial void ratio is larger than e_cr determined in monotomc loading. An empirical equation for the volumetric strain of gravelly sands is proposed considering the effects of Dr, cyclic stress ratio and the number of cyclic loading.

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The investigation is focussing on the fill remains to make clear the geotechnical properties and its construction technique. The standard penetration test was performed at Yoshinogari north burial mound and a series of laboratory tests was conducted on undisturbed and compacted samples. Also, these results are compared with those of the other three fill remains. By carrying out the compaction tests and making the model assuming the construction of the Yoshinogari north burial mound, the construction technique and the prediction on the needed number of days for the construction were shown.

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In this paper, the effect of the uncertainties associated with the spatial distribution of rock fractures on the evaluation of loss due to slope failure was discussed. In detail, in order to model the spatial distribution of rock fractures based on stochastic approach, the methodology related to fracture network model was adopted. Finally, the conclusion made it obvious that the results associated with the evaluation of loss are more seriously affected by the spatial distribution of rock fractures, comparing with the effect of other parameters on the results.

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The purpose of this study is to obtain the failure mechanism of shotcrete on fractured rocks. Firstly, the failure accidents of shotcrete were surveyed. These results implied the failure process; (1) Occurrence of un-bond tensile between shotcrete and bedrock by loading of fractured rocks, (2) Shotcrete including the bond fracture became a beam structure, (3) Flexural failure of beam shotcrete happened by loading of bedrocks. The tensile bond strength test and collapse-simulated test were carried out in order to verify these failure mechanics. From these tests results, reinforced shotcrete by using net or fiber was effective to prevent brittle fracture of shotcrete.

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In order to estimate the effects of coupled thermal-hydraulic-mechanical phenomena in near-field for geological disposal of high-level radioactive waste on a vast groundwater flow system, a far-field anlaysis was simulated based on the results of the simulation of coupled phenomena in near-field using averaged tensor and heat flux.
From the results of the coupled analyses of near-field and far-fled it was clarified that groundwater flow system was influenced by coupled phenomena in near-field. Moreover, it can be said that groundwater flux into a disposal tunnel is regarded as a complement to safety assessment of a disposal because it strongly correlates with traveling time of groundwater.

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A series of triaxial compression test was carried out using Holocene as well as Pleistocene clay samples from the seabed of Osaka Bay retrieved as deep as 155m in depth. In the undrained tests, the specimen's deformation was measured locally by using a newly developed system. In each test, the variation of elastic shear wave velocity with stress was also monitored using a set of bender elements. In this paper, not only the compressibility but also the shear characteristics was carefully examined over a wide strain range. In comparing the behaviour between the natural clays and the reconstituted clays, the aging effects were manifested in terms of the deformation-strength characteristics of the natural sedimentary clays.

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There are a lot of experiences of using granulated blast furnace slag for port area. At the beginning of the utilization, there are a lot of unknown factors about the long term characteristics of the material. Solidification problem is one of the most interested unknown factors. In this study, geotechnical investigations have done in several sites and discussions as to the change of mechanical characteristics of the material in long term has done. It is clarified from this study that there are some large variance in mechanical characteristics of this material in-situ and this material will solidify if it is under the water table, its solidified strength is 85-1760kN/m² and the internal friction angle is more than 37 degree in residual condition. The permeability of the material in the solid state is 10^-3cm/sec.

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The purpose of this study is to propose a method of measuring the density of cohesive-soil ground with a split spoon sampler with built-in tubes. An optimal method was devised for measuring the density of samples taken from cohesive-soil ground with a split spoon sampler with built-in tubes. Then, a field experiment was carried out using a split spoon sampler with built-in tubes and a thin-wall sampler. The wet density, water content, dry density, and fine-grained fraction of samples by the split spoon sampler with build-in tubes were checked well with those of samples by the thin-wall sampler, proving the proposed method to be practical enough.

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