A Simple Elastoplastic Model for Normally and Over Consolidated Soils with Unified Material Parameters

To investigate the realistic ground behavior during tunneling, a new device has been developed. With the new device, model tests of tunnel excavation considering an existing tunnel and an existing building were carried out. Non-linear finite element analyses corresponding to the model tests were also conducted using FEMtij-2D software where an elastoplastic subloading t
 ij
 model was used to describe the mechanical behavior of soil. Earth pressure distribution around the tunnels and ground movements during tunnel excavation depend on the distance and position between the twin tunnels. There is a significant effect of tunneling on the existing foundation of building even in the case where the tunnel is constructed in deep underground. The numerical analyses capture well the results of the model tests.

Investigation of influence of tunneling on existing building and tunnel: model tests and numerical simulations

Behavior of Ground and Response of Existing Foundation Due to Tunneling

Ground Behavior Due to Tunnel Excavation with Existing Foundation

3D finite element modelling optimization for deep tunnels with material nonlinearity

3D effects on earth pressure and displacements during tunnel excavations

The trolley contactors installed on trolley wires are used to detect streetcars' positions and control their routes. The passage of a streetcar is detected when the pantograph contacts the mechanical switch of the trolley contactor. This requires periodic maintenances in high places, which are heavy burdens. Global Navigation Satellite System (GNSS) has been considered as an alternative to the trolley contactors. The accuracy of GNSS varies greatly depending on the surrounding environment. It is necessary to evaluate the accuracy of streetcar position detection using GNSS in advance. We propose the evaluation technique for the accuracy of streetcar position detection using GNSS. 

路面電車における衛星測位の精度評価手法の検討

The electric railway is an environment‐friendly transportation system. An energy‐saving operation with a low cost and high energy‐saving efficiency is often considered to further decrease energy consumption. An Automatic Train Operation (ATO) system has the advantage of energy‐saving because a train can be controlled by an on‐board computer. However, many railway lines are still being operated by drivers and controlled via manual operation in addition, energy managements often become difficult for drivers and operators. Therefore, a study of energy‐saving manual operation is desired. Energy verification of a manual operation is difficult because an adequate experiment has several constraints and trial periods are limited. Moreover, it requires a considerable amount of time and effort. In this study, an energy evaluation system is developed to calculate the energy consumed by a train when a driver manually operates it through adding an advanced calculation device to a conventional railway simulator. Consequently, the evaluation system contributes to carry out simple experiments with a short duration.

Daisuke Yamaguchi

Papers

3D effects on earth pressure and displacements during tunnel excavations

路面電車における衛星測位の精度評価手法の検討

Development of energy evaluation system during manual operation using train simulator