莫斯科地铁的特点及对我国地铁的启示

全面介绍莫斯科地铁在线网规模、车站设计、运营组织等方面的理念及特点,详细分析莫斯科地铁客流量大、运营效率高的原因,以期为我国未来地铁发展提供借鉴.     

地下施工柴油机喷油泵的使用

喷油泵是柴油机燃油供系统的重要部件，针对地下施工中的实际情况，提出了加强使用维护以保证喷油泵正常工作的几种方法及注意事项。     

地下连续墙作为桥梁基础在软土地区的应用

本文以上海浦东国际机场1号桥的设计为背景,介绍了地下连续墙做为桥梁基础的计算模型的建立、计算参数的取值以及构造处理措施。结果表明:当条件受限制时,地下连续墙不失为一种较好的基础型式。     

建筑物受深基坑开挖影响的显式差分分析

在基坑开挖过程中，临近重要建筑物的保护是一个重要的研究课题，通过天津地铁营口道车站深基坑开挖的模拟分析可以看出，地表沉降、墙体变位、基坑隆起三者之间存在着明显的关系，临近基坑建筑物沉降变形与其基坑的接近度有明显关系，施工过程中应综合考虑技术可行性、安全、环保、质量、工期、效益等因素采取保护措施。     

大断面地铁车站隧道软弱围岩渐进破坏规律模型试验研究

以贵阳市地铁2号线阳明祠车站为背景,采用室内模型试验模拟大断面地铁车站施工过程中隧道塌方破坏过程,明确施工期间大断面隧道塌方破坏过程机制,对比分析围岩和路面的变形。结果表明:通过围岩重力作用模拟隧道施工过程中塌方过程,与实际塌方过程基本吻合,弥补了常规加载破坏的不足;围岩渐进破坏过程表现为裂隙出现-裂隙发展-裂隙贯通-围岩塌方,支护渐进破坏过程表现为变形缓慢增加-变形快速增加-裂缝快速发展-支护破坏;围岩渐进破坏与支护渐进破坏相互作用,共同发展;在实际施工过程中,当支护变形大幅增加时,应增加支护强度,同时还应及时注浆、打设长锚杆,以减缓围岩裂隙发展,阻断围岩渐进破坏过程。     

A novel approach for the modelling of air quality dynamics in underground railway stations

Indoor air quality in subterranean train stations is a concern in many places around the globe. However, due to the specificity of each case, numerous parameters of the problem remain unknown, such as the braking discs particle emission rate, the ventilation rate of the station or the complete particle size distribution of the emitted particles. In this study the problem of modelling PM₁₀ concentration evolution in relation with train traffic is hence addressed with a particle-mass conservation model which parameters are fitted using a genetic algorithm. The parameters of the model allow to reproduce the dynamics and amplitude of four field data sets from the French and Swedish underground contexts and comply with realistic bounds in terms of emissions, deposition and ventilation rate.     

高架快速路上跨宝鸡东编组站方案比选

宝鸡市斗中路高架快速路,跨越宝鸡东编组站的10股轨道线和铁路专用线,同时桥下的城市主干路以框架桥的形式下穿宝鸡东编组站。桥位处需保留现状的地面交通、铁路框架桥和周围的高层建筑,桥址处空间局促,建设条件复杂,导致桥梁墩位布置困难。桥梁的布置方案与施工方案相互影响和制约。上跨方案是控制整条快速路的关键节点。综合考虑主墩的合理位置、恰当的孔跨布置和适宜的施工方案,对矮塔斜拉桥、刚构桥等方案进行详细的对比分析,确定采用(97+97)m的转体刚构桥方案。该方案的安全性和经济性均较优。该桥方案的研究过程和方法,为类似的复杂城市环境下,建设高架桥梁跨越铁路编组站提供参考和借鉴。     

Fast-charging station choice behavior among battery electric vehicle users

This study explores how battery electric vehicle users choose where to fast-charge their vehicles from a set of charging stations, as well as the distance by which they are generally willing to detour for fast-charging. The focus is on fast-charging events during trips that include just one fast-charge between origin and destination in Kanagawa Prefecture, Japan. Mixed logit models with and without a threshold effect for detour distance are applied to panel data extracted from a two-year field trial on battery electric vehicle usage in Japan. Findings from the mixed logit model with threshold show that private users are generally willing to detour up to about 1750 m on working days and 750 m on non-working days, while the distance is 500 m for commercial users on both working and non-working days. Users in general prefer to charge at stations requiring a shorter detour and use chargers located at gas stations, and are significantly affected by the remaining charge. Commercial users prefer to charge at stations encountered earlier along their paths, while only private users traveling on working days show such preference and they turn to prefer the stations encountered later when choosing a station in peak hours. Only private users traveling on working days show a strong preference for free charging. Commercial users tend to pay for charging at a station within 500 m detour distance. The fast charging station choice behavior is heterogeneous among users. These findings provide a basis for early planning of a public fast charging infrastructure.     

A cost-competitiveness analysis of charging infrastructure for electric bus operations

This study investigates the cost competitiveness of different types of charging infrastructure, including charging stations, charging lanes (via charging-while-driving technologies) and battery swapping stations, in support of an electric public transit system. To this end, we first establish mathematical models to investigate the optimal deployment of various charging facilities along the transit line and determine the optimal size of the electric bus fleet, as well as their batteries, to minimize total infrastructure and fleet costs while guaranteeing service frequency and satisfying the charging needs of the transit system. We then conduct an empirical analysis utilizing available real-world data. The results suggest that: (1) the service frequency, circulation length, and operating speed of a transit system may have a great impact on the cost competitiveness of different charging infrastructure; (2) charging lanes enabled by currently available inductive wireless charging technology are cost competitive for most of the existing bus rapid transit corridors; (3) swapping stations can yield a lower total cost than charging lanes and charging stations for transit systems with high operating speed and low service frequency; (4) charging stations are cost competitive only for transit systems with very low service frequency and short circulation; and (5) the key to making charging lanes more competitive for transit systems with low service frequency and high operating speed is to reduce their unit-length construction cost or enhance their charging power.     

基于PLC的模糊频载调节器设计

介绍可编程序控制器(PLC)实现船舶电站模糊调频调载的软硬件实现方法,采用离线计算、在线查表的方法在PLC上实现模糊控制,利用硬件在环仿真进行试验研究,结果表明,智能频载控制器具有较好的稳、动态性能。