This paper reports on the influence analysis and the measurement of underpinning the viaduct of Sendai station on Tohoku Shinkansen in the construction of the subway which cross under the viaduct. For operating Shinkansen safety, the virtical displacement of the viaduct have been controlled by limiting 3mm. We are measuring the subsidence and the inclination, etc of the viaduct automatically. And the result of this measurement agrees with the analysis done before construction well. The viaduct dose not displace harmfully now. We are measuring in the construction, and we are appling the result of measurement to construction.

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The Works, located in Yamashina, the eastern part of Kyoto City, consists of construction of a underground subway station (293m in total length) which is three-storied, reinforced concrete frame structure. The features of the Works is as follows:
(1) The construction work was carried out under the road on which heavy traffic is and also the train line is operated.
(2) To keep the construction space under the road, a large scale pipe-roof method was adopted for underpinning the road and the train line.
(3) Large excavation work and construction of the station were carried out inside the space made by the pipe-roof method.

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Several finite element procedures for frictionless- or friction-contact problems have been proposed for the case in which node-to-node contact no longer holds. One of the typical computational algorithmes have been generalized by using a perturbed Lagrangian and localized mixed concepts. The numerical parametric analyses carried out by using the algorithm to study the contact influence between a shield machine and the surrounding ground. In this paper, we descrive the results of the analyses and a mechanism of the excessive loading pressure occurring during shield tunnel construction.

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Model tests on the closely constructed parallel shield tunnels are carried out in order to evaluate the longitudinal behavior of the existing tunnel due to the construction of new tunnel. from the tests, it is confirmed that the earth pressure acting upon the existing tunnel is changed according to not only the distance from the extreme point to the strip but also the difference of the bending rigidity of the strip.On this paper we tried to evaluate the earth pressure acting upon the existing tunnel by compared the data from the model tests with the 3-D FEM analysis for the model tests. The structural model in which ground is replaced with the suitable elastic springs is introduced. As a result, the model explained well the behavior of the existing tunnel.

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This paper discusses the earth pressure acting on shield segments in soft clay with the results of field measurments data and numerical analyses. The data employed in this study were obtained at the sites of Sumidagawa Shield Tunnel and Tonan-Kansen Shield Tunnel, which were constructed in the soft alluvial clay at the depth of 13-29m from the ground surface.This study will be great use as a guide for designing the shield tunnels of similar cases.

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When shield tunnel is constructed in the deep underground which is a stiff and reliable ground comparatively it is uneconomical to apply the usual design method of tunnel lining as it is.
The lateral loading model tests are carried out to rationalize the design method for the shield tunnel lining. Two types of analyses are used to evaluate the ground reaction at invert. One analysis treat it as uniform load and the ather treat it by ground spring.
From the analyses, result of the tests are in the middle of these analyses.

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The Higashi-roppongi station is a new station of the Namboku-line which is under construction by the Teito Rapid Transit Authority. And this new station is situated in proximity to the metropolitan expressway structures and worked in the ground with high groundwater levels. Therefore it has been planed to carry out the pre-excavation timbering by transverse diaphragm and the wet excavation for safety works. This report will examine these special methods and analyze influences on the adjacent expressway structures.

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This report describes the drilling of a deep vertical shaft in a short period of time while preserving the environment and maintaining safety at a narrow site nearby residential dwelling.
The method of drilling, newly developed, integrates use of a reverse-circulation-drill for vertical shaft excavation, round steel supports for earth retention, and caisson using pressurizing.

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We checked the accuracy of the method used to calculate ground spring when designing an underground diaphragm wall used as a main underground structure. This was done by comparing frame analysis values with field measurements. We found that the results obtained with the method currently being used tend to be larger than measured values for downward deformation of the middle portion of the bottom slab. We closely examined and adjusted the ground spring constant between the slab (or the diaphragm wall) and the ground. By doing so we were able to obtain analytical results that were close to the results obtained by actual measurement.

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In pipe-roof method of excavation, it is inevitable that ground surface settlement. It is important for the safe train operation to predict such settlement in excavation.
We simulated two in-situ measurements about behavior of pipe-roofing. For simulation, Elasto-plastic Method was used. As a result, we propose a method of pipe-roofing displacement considering ground reaction coefficient, plasticizing of adjacent face and redistribution of earth pressure with pipe-roofing displacement.

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The seismic force of Hanshin-Awaji earthquake which considerably exceeded the earthquake-proof design condition, brought about enormous damage on the structures.Taking these damages into consideration Teito Rapid Transit Authority examined the possibility of liquefaction around the entrance of Tozai-Line and acquired the conclusion that some measures to cope with these situation should be taken.For this reason Teito Rapid Transit Authority prevents the damage of liquefaction by constructing the steel sheet-pile with drain and soil improvement of JSG. This paper is on the possibility of liquefaction, the selection of the measures for liquefaction and the measures it'sself.

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The two hinged arch-culvert treated in this paper, is a specific structural type with contacting joint between roof and side-wall, was devised in France. However the seismic performance of the two hinged arch-culvert is not yet conformed.
The aim of this paper is to verify the seismic performance of this structural type in order to use in Japan.
An experiment of static cyclic-shear-deformation for this surrounded by sand soil, was carried out for examining the ductility of this due to soil deformation under the earthquake. The test result show there, is sufficient seismic performance even though the relative displacement between roof and footing is more than 3% of the specimen's height.

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Shield tunneling method has been widely applied to the construction of underground structures in urban area and a demand for long distance tunneling under high underground water pressure is growing recently.
To deal with the demand, a tail-end-sealing system of shield tunneling machine is treated in this report among other technology developments. We have designed a high durability new tail-end-sealing system which is made by filling up ordinary wire brush with poly urethane form, and a series of fundamental efficiency tests' has been carried out.
As a result, it was clarified that the new tail-end-sealing system has higher sealing performance and higher durability than the ordinary wire brush type tail seal.

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Generally, the large-section slurry shield is equipped with the jack thrust of 1, 100-1, 400 kN/m² and the cutter torque coefficient of α=10-14 according to the past record of delivery. Since this equipment capacity is far above the actual achievement during excavation, it is considered reasonable, as a result of analysis of subway construction of Teito Rapid Transit Authority, to set the practical thrust at 900-950 kN/m² and the cutter torque coefficent at α=9-9.5

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Urban shield tunnel tend to be excavated deeper and deeper recently, because of underground space utilities effectively. So it is expected large depth and steep gradient tunnel to increase in future.
This report describes the construction plan and results of overcoming sharp curves and steep gradient under high water pressure by slurry type shield driving method.

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This report describes the analysis of shield tunnel lining behavior at sharply curved portion based on the result of in-situ measurements carried out during the construction.
By the measurements, the acting mode and scale of shield driving force at sharply curved tunnel with large section and large depth and the arising mode and scale of the tunnel sectional force caused by the driving force were grasped. Through the trial of numerical analysis fitting the calculation with these result of the investigation, boundary conditions, flexual rigidity of tunnel axis, and loading method of shield propulsion which the axial tunnel structural model requires were clarified.

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Generally, chemical grouting is used for cut-off and soil improvement and demands a technique of permeation grouting restraining from making ground distorted as minimum as possible. On the other hand, the technique meant that heaving up the ground by grouting is appropriated to compensate structures for settlement exists. This paper refers to compensation Grouting which is undertaken to limit settlements of viaduct piers during tunnel construction in London. Monitoring data of settlement of viaduct piers during running tunnel construction indicate that compensation grouting proved to be successful in limiting settlement less than a specified allowable settlement.

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