The stress analysis based on the result of the temperature analysis and the moisture transfer analysis is necessary in order to predict the initial crack of tunnel lining concrete. However, the input data of properties, such as the thermal conductivity of concrete has a direct influence on the precision of analysis.
 In this study, the inverse thermal analysis using particle swarm optimization that presumed the thermal properties from the temperature measurement result in the construction site is proposed. Furthermore, the factors that influences the initial crack, such as thermal stress, drying shrinkage, form removal etc. are examined by the analysis that used the identified properties.

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 Recently a cast-in-place concrete lining support system using a shield machine, which is called SENS, has been applied for railway tunnels. During the construction by SENS, the inner mold tends to move upwards because of buoyancy due to water pressure and concrete pressure. In order to estimate earth pressure acting on inner mold or lining of SENS, it is necessary to consider soil-inner mold and soillining interaction according to three dimensional behavior of the inner mold and lining. As the analysis technique, in general, there are a two-dimensional framed structure analysis and a three-dimensional finite element analysis. The former can not consider the three-dimensional effect of the tunnel, and the latter can not represent the behavior of the lining that is lifted by buoyancy due to water pressure and concrete pressure.
 Therefore, we have developed a three-dimensional analysis model taking into account the loading conditions, construction process, and factors to affect the behavior of the inner mold and lining in SENS.
 In this paper, we implemented a parametric analysis on some properties that define the ground reaction curve. Those properties are the initial displacement, the coefficient of horizontal earth pressure and the coefficient of subground reaction. In order to verify the validity of the analytical model, the effects of the three parameters were examined by the analysis results. The measured bending moment and axial force were compared with the calculated ones, and the values of the parameters were estimeted to have a good fitting. As a result, it was found that the proposed model could simulate the inner mold behavior reasonably well.

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 In order to clarify the behavior of closely spaced twin tunnels without center pillar during excavation, analysis on the field measurement data obtained at closely spaced twin tunnels construction sites and numerical analysis using 3D and 2D finite different code were carried out. The results show that the influence of the second tunnel excavation on the first tunnel appears mainly as the increase of the sectional forces in support structure at the sidewall on the second tunnel side with the rapid change of the stress in the soil pillar. The load acting on the support structure of both tunnels at the soil pillar side varies depending on the distance between two tunnels, overburden height and deformation modulus of ground, and the support structure may support a load up to full overburden weight in some cases.

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 We propose a numerical model that can simulate the creep and strain softening behavior at the time.The model was based on the calculation of relaxation. For estimating the rate of relaxation, the Arrhenius equation was refered. After the numerical model was installed in FDM code, the tests under constant load and under constant strain rate about the soft rock was simulated. As a result, the creep behavior from primary to tertiary creep and also strain softening behavior are well agreed with the test's results. Lastly, we checked the applicability of the numerical model to tunnel excavation problem by some calculations for virtual tunnel excavation.

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 In Japan, it is necessary to excavate many hard rock tunnels using a heavy weight (200-300kW class) axial and transverse cutter head type roadheaders, which has reason for various conditions of saving the environment from the construction site and so on. And the performance of a heavy weight axial and transverse cutter head type roadheaders is a critical issue in assessing technical and economic feasibility of its application in many tunneling projects.
 Therefore, we has established a database of heavy weight axial and transverse cutter head type road-headers performance, which based on the interview for engineer's of many tunnel construction projects. This database contains field data from the civil construction operations all over Japan, includes a variety of heavy weight roadheaders of different geotechnical conditions and different cutter head type. And, this database refers to accurate estimation of the production rate, machine utilization and picks consumption for different geological units to be encountered on the tunnel project planning.
 This paper presents and discusses the performance estimation model of instantaneous cutting rate (ICR) and pick consumption which was introduced rock quality designation index (RQD) from this database. Especially this database established form hard rock tunnel excavated data using heavy weight (200-300kW class), axial and transverse cutter head type road headers.

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 In a mountain tunnel excavation, the air environment is worsened by the various types of dusts generated with rock drilling, blasting, conveyance of surplus rocks, and so on. In general, the various ventilation systems are applied for improvement of air quality around the tunnel face.
 In this paper, two ventilation systems were suggested. The numerical analyses were performed for the comparative discussion. These analysis results showed that the suggested systems have ventilation performance higher than the conventional systems about from 30 % to 35%.

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 In this study, the area of chloride damage in the cut and cover tunnel was investigated and numerical simulation was carried out with chloride diffusion analysis copuled with ground water. It had been understood that chloride damage was main ploblem in maintenance of subway tunnels have been indicated by last results of our investigation and the area of chloride damage occurs at the limit part nearby chloride water leakage. First, the chloride density of leakage was mesuered. As the results, it is found that the wide of chloride leakage was about 50m from the edge of tidal rivers. Second, numerical simureation is carried out to study time dependence of chloride movement. The result of simuration was good agreement with the insute mesuerement.

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 Attenuation properties of subway-induced ground vibration propagated from cut-and-cover tunnels were experimentally investigated to improve the accuracy of empirical prediction methods for the Vibration Level and ground-borne noise level in buildings. Vibration accelerations both in the tunnels and on the ground were measured in and around the Tokyo area. This paper presents distributed levels of measured acceleration in the tunnels and ground. Dependency of attenuation properties on frequency is examined, and internal damping in every 1/3 octave band are calculated based on the Bornitz formula. Damping factors with ground conditions are also discussed.

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