A lot of tightness system for pressurized gas storage in excavated rock caverns, such as compressed air energy storage, natural gas storage and so on, had been proposed. However any reliable suggested method had not been established in Japan. For lining tightness system, which is assumed the most effective method has also not come up standard. Therefore it is very seldom to discuss the suitability of lining system concerned with the financial basis.
We have proposed a rubber sprayed lining system which is assumed the most economical one, and also have conducted a structural design based on the result of laboratory tests. Finally we have adapted the proposed method to the in-situ storage cavern in Kamioka mine and also conducted the storage tests.
In this paper we have shown the examination results for the evaluation of proposed lining.

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This paper shows an application of numerical analysis to design of supporting for cavern at underground power station based on experience of constructions and measurements. In order to determine actual quantity of supporting for cavern, it is neccesary not only to define rock model but also to apply an appropriate numerical analysis which can evaluate effects of supporting. At KAZUNOGAWA power station, an analysis which can consider the strain-softening after rock failure was applied to such design. Consequently, effects of supporting could be evaluated and then design of supporting could be carried out rationally. This paper also shows comparison between measurements and analysis in order to confirm suitability of analysis.

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Due to the recent demand for cost reduction and for the rational design to cope with for various needs in shield tunnel constniction, many types of segment lining have been attempted. Most shield linings consist of rectangular shaped segment, but authors are developing trapezoidal shape segment.
As the basis of this work, a study on the joint characteristics of rectangular segment has been carried out by using three dimensional freezing photo-elastic method. First the applicability of the method in the study is discussed. Although the stress distribution obtained is somewhat different from actual situation due to the difficulty of loading method of axial force, the results show the method is very helpful to study overall stress as well as local distribution at joint by giving visual pattern. The stress distribution patterns of segmented lining of rectangular type are shown in comparison with the uniform jointless lining.

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A special vertical anchor bolt has been designed and conducted to prevent ground surface settlement which is the biggest problem for application of the NATM to thinly covered unconsolidated ground in urban areas. This paper analyses the changes with time of the displacement of the ground surface, mid-ground and crown of a tunnel and of the axial force of the bolt, demonstrating the positive effects of the vertical anchor bolt based on different measurement results as well as behavior between cases with and without such anchor bolts. Having analysed the positive effects of vertical anchor bolts placed outside the cutting cross-section at each stage of division of excavating section, the paper proposes an appropriate distribution of vertical anchor bolts to facilitate the formation of the be-am and ground arch in the ground above a tunnel. The effects of the bolts are logically evaluated and validated by the actual measurement and analysis results.

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Collapses of cutting faces and air blow are reported to have occurred during tunneling earth pressure shield method in sand beds and gravel beds with high permeability.
The purposes of this study were to find the improved fluidity of excavated soils in which earth pressure type shields are applicable and to clarify the scope of conditions in which this type of shield is usable.
As a result, it was learned that the admixed materials mixing ratio on the soil properties is has a high possibility of being actually used in tunnels.

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In this study, countermeasures using dampers were investigated against wind induced vibrations and angular bent phenomena. A newly countermeasure, which uses a combination of HDR and dampers, can make dampers installed in lower position than the conventional one which uses a combination of a rubber and dampers. Therefore it can be superior in the easiness in installation and maintenance, and in aesthetic view. It was applied to Tsurumi Tsubasa Bridge and its effectiveness was confirmed in model tests, vibration tests and field observation.

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We will propose a simulation method wherein energy at a forecast point be integrated by repeating a lot of reflexes in a geometrical sound way under the boundary condition on reflex side on the elevated tracks via the Monte Carlo Method. Also, based on the result of this simulation, we denote brief calculation method of noise taking reflex noise into our consideration quantitatively by defining reflex effect co-efficiency at forecast site in addition to the former formulations of the Acoustical Society of Japan. This method easily makes evaluation by the formation of reflex model possible which had been taken in elevated bridges, sound insulation walls, relationship of road-side position, surrounding land shape, arrangement position of sound-absorbing materials.

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This paper deals with two kinds of special spacers with damping device (TYPE-S, TYPE-M) for suppressing wake galloping in tandem cables of cable-stayed bridges. It was ascertained that the structural damping characteristics with these types of dampers for the out of phase cables would be very dependent on the torsional rigidity of the cable. Effectiveness of TYPE-S and TYPE-M were also compared with respect to diameter of the cables. From these results, some useful informations are obtained for the vibration control of wake galloping by the installation of special spacers with damping device.

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Highly fluidized concrete is now coming to a practical stage of use and its applicability has been verified through various kinds of concrete constructions. In this paper, the authors proposed the slump-flow value and V-shaped funnel value that should be required for each structure based on data obtained from actual construction works. And also we proposed the procedure for selecting mix proportion of the concrete with viscosity modifying agent of welan gum from the results of experiments both on fresh and hardened properties of the concrete. The procedure were used successfully in actual construction works.

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The objective of this paper is to innovate a new compaction machinery by comparing experimentally the effects of two-axle, two wheel road roller and tracked vehicle mounting a centrifugal oscillator on the vibro-compaction of a high lifted decomposed granite sandy soil. Measuring the normal pressure distribution and the vertical and horizontal acceleration in the soil, the effects of both the vehicles having the same total weight on the increment of the soil density have been considered theoretically. As the results, the tracked vehicle showed the larger cone index and soil density at the shallow and intermediate stratum. Especially, the ratio of the horizontal and vertical value of maximum impact force was large enough at the, deep stratum, so that an optimal alternative shear strain to promote the increment of soil density due to the dilatancy effect was developed at the whole range of the high lifted soil stratum.

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We analysis the characteristics of the weathering of cut-off slope using the long-term measurement data and classify the collapsed and the non-collapsed cut-off slope using quantification theory type III based on the evaluation factors that are slope evaluation factors, rainfall factors, the weathering, and the combination with them. From the results, it is clear that an influence of the weathering for the result of classification is very small and the result has decided by slope evaluation factors and rainfall factors. Therefore, using the slope evaluation factors together with rainfall factors is more effective than using three factors to classify the collapsed and the non-collapsed slope

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Blasting vibration during the construction of underground caverns causes unwanted damage to the surrounding rock. In this research, the effects of slot (holes continuously drilled along the perimeter of the tunnel) on the blast induced vibration reduction were investigated by the vibration measurement. The results revealed that the slot reduced the vibration in the surrounding rock to 1/3 in terms of vibration constant K. The reduction in vibration can be attributed to the decrease of burden and the reflection and diffraction of stress waves by the surface created by the slots.

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This paper presents the verification of a theoretical equation proposed by the authors on water stopping mechanism of earth pressure balanced shields subuject to high water pressure.
Compararison of theoreticaly predicted phenomenon with practical one obtained from shield excavations, and the investigation from trial result of theoretical equation using the data of shield machine has been conducted. The results revealed that the proposed theoretical equation well represents a practical applicability.
And it has became clear that the equation has a sufficient validity in designing shield machine for practical purpose.

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The aim of this study is to develop a new function of bridge management system which is currently being developed. This function is able to offer some maintenance palns based on a combination of maintenance cost minimization and quality maximization approach. Then, the Genetic Algorithm (GA) is adopted in this optimum problem. The results suggest that the GA is more effective for this problem than the other algorithm. Furthermore, by applying this function to an existing bridge, it has been verified that employed optimum method is effective.

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The authors participated in the construction of Singapore Mass Rapid Transit Systems as the geotechnical consultants for the Mass Rapid Transit Corporation. Through the experience, relations among the project owner, the contractor, and the consultant are discussed. In addition, detailed discussions are made on claims, which are not very familiar to Japanese engineers.

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