Some Predictions of Deformations from Tram Track Construction in a Structure-Embankment Transition Zone

AbstractBased on a construction project of a tram line in Nanjing City of China, the influence of a tram track construction on the deformation characteristics of an adjacent metro station and tunnels is investigated. Because a section of the tram track is designed to be constructed in the vicinity of the connection between a metro station and metro tunnels, the foundation of the tram track is changed from the station structure to the normal embankment. As a result, deformations from tram track construction in this structure-embankment transition zone will be serious. In order to protect the metro station and the twin tunnels from the construction-induced deformation and long term settlement caused by tram trains, a recommended treatment of the structure-embankment transition zone is suggested according to the property of the surrounding soils. The construction process of the tram track over the metro station and the tunnels is simulated by a finite element analysis (FEA) method. The deformation characteristics of the metro station and tunnels are calculated. Results indicate that with the recommended transition zone design the deformation response of the adjacent underground structures can be well controlled and the transition performance of the tram track transition zone can be improved

Damage Effect of Terrorist Attack Explosion-induced Shock Wave in a Double-deck Island Platform Metro Station

The objective of this research was to reasonably assess the damage to people and station structures caused by terrorist attack explosion at metro stations, taking the Liyuan station of Wuhan metro which adopts double-deck island platform as an typical example. The TNT explosion process inside the metro station was calculated and analyzed using the dynamic finite element numerical simulation software LS-DYNA. First, the peak overpressure curve and the positive pressure time curve of the shock wave of explosive under the condition of confined space in the metro station were obtained. Then, through the comparison and analysis of the theoretical formulas of explosive shock wave propagation characteristics, the accuracy and reliability of numerical calculation methods and model parameters were verified. At last, combining with the overpressure criterion of shock wave in explosive air, the distribution characteristics of the casualties in the metro station under the explosion shock wave are analyzed, and the dynamic response and damage effect of the pillar structure of the metro station under the explosion shock wave are studied

ASSETS OF MODEL METRO STATION AND THEIR CRITICALITY

The paper deals with the identification of protected assets in the model metro station, which is a part of critical infrastructure in Praha; and with the identification of their criticality. A metro station is used by a lot of people and it involves many expensive components and devices with interdependences which form a system of systems. The system, its components and fittings are very vulnerable to damages from disasters of many kinds. The first step of ensuring metro station safety is the identification of basic metro assets which are important for safe metro operation and for human (employee and passengers) security and environment safety; and the other is determination of criticalities of considered assets with taking into account all relevant sources of hazards. These facts are input data for further processes which are important for safe metro operation under the different conditions

NAVMETRO®: PRELIMINARY STUDY APPLICATIONS OF USABILITY ASSESSMENT METHODS

NAVMETRO® is a spoken dialogue system that provides information and a guidance function to the people with visual disabilities on Trindade’s metro station, in Porto, Portugal. The system usability in addition to assure the quality dialogue for all costumers should ensure the success in the guidance on the desirable way in the metro station. This article presents the results of the preliminary assessment developed on NAVMETRO® and that represents an important stage of the usability assessment of this system

Sit Down Together at a Table of Brotherhood : Martin Luther King Jr. Memorial

As we walked along the tidal basin back toward the Smithsonian Metro Station, I began to cry. Just a few tears, here and there, welled in my eyes. It wasn\u27t the monument or the quotes. It wasn\u27t the deep feelings I had looking at his face. It was overhearing a simple conversation. Two 30-something black women in a group of tourists were talking to one another about photos. You need to get your picture taken, girl, one asks the other. Why? she responds, I\u27ve got plenty of pictures. To prove you were here, the first woman responds. [excerpt

An estimation model on electricity consumption of new metro stations

Electricity consumption of metro stations increases sharply with expansion of a metro network and this has been a growing cause for concern. Based on relevant historical data from existing metro stations, this paper proposes a support vector regression (SVR) model to estimate daily electricity consumption of a newly constructed metro station. The model considers some major factors influencing the electricity consumption of metro station in terms of both the interior design scheme of a station (e.g., layout of the station and allocation of facilities) and external factors (e.g., passenger volume, air temperature and relative humidity). A genetic algorithm with five-fold cross-validation is used to optimize the hyper-parameters of the SVR model in order to improve its accuracy in estimating the electricity consumption of a metro station (ECMS). With the optimized hyper-parameters, results from case studies on the Beijing Subway showed that the estimating accuracy of the proposed SVR model could reach up to 95% and the correlation coefficient was 0.89. It was demonstrated that the proposed model could outperform the traditional methods which use a back-propagation neural network or multivariate linear regression. The method presented in this paper can be an adequate tool for estimating the ECMS and should further assist in the delivery of new, energy-efficient metro stations

Sunrise with Lincoln and Meanings with Chuck

I walked 150 years on Monday. I walked across a great chasm of history. Physically, I walked from the Arlington Cemetery Metro Station across Memorial Bridge, then continued down the National Mall to 4th Street, where I witnessed one of the most peculiar regularly scheduled celebrations that Americans observe: the Inauguration of the President. But along the way, I met the past alive on the landscape. I watched the sky turn from murky black into hopeful, bright pink and orange sitting alongside the savior of the nation. Lincoln and I watched as the early light of sunrise silhouetted the brightly-lit Washington Monument. We watched the dark melt to light, the chaos and unknown melt into bright order. [excerpt

MECHANICAL RESPONSE ANALYSIS AND TREATMENT MEASURES OF PARTITION WALL OF METRO STATION

In the process of metro station construction, the partition wall is usually used to prevent the displacement of the soil behind the wall to ensure the construction platform. This research aims to analyze the response of partition wall to keep the safety of the structure. The time-horizontal displacement and cracks of the partition wall are measured during the process of metro station construction. The finite element software FLAC 3D is used to simulate the response of partition wall, and the reasons of partition wall cracking and displacement are analyzed by finite element simulation and measurement data. The stiffness and self-stability of the partition wall in the station is powerful, the stress concentration appeared on the central area and caused cracks of the partition wall. Reducing the pressure exerted on the partition wall and shifting partial pressure exerted on the partition wall by the construction of the medium plate can solve the tress concentration problem. Through the data analysis of the strengthened partition wall, the reinforcement effect is good, ensuring the safety of the subsequent construction. The causes of partition wall cracking are found during process of metro station construction, and the solution proposed in this paper is effective. Engineers can refer to this paper to analyze the response of partition wall in the construction of similar structures, which can ensure construction safety and reduce construction cost