盾构机刀盘的地质适应性设计研究

为了提高盾构机的地质适应性,减少盾构施工过程中因地质因素造成的工程问题,盾构机刀盘必须根据地质条件进行地质适应性设计.文章基于多个盾构隧道施工实践,分析了国内外盾构隧道施工中出现的掘进困难、刀盘刀具快速磨损、结泥饼和开挖面失稳等工程问题,发现刀盘对岩土类型、岩土物理力学性质和水文地质条件不适应是产生这些工程问题的根本原因.基于岩土体与刀盘相互作用的机理和盾构施工经验,文章分别总结了刀盘结构、刀具选型布置和刀盘碴土改良装置在地质适应性方面的设计经验.     

盾构机的集中润滑

盾构机中的集中润滑是作用于盾构机的关键部位刀盘驱动大轴承、唇口密封等。刀盘驱动大轴承润滑不良，会带来大轴承的咬死，造成刀盘不能工作，影响盾构使用；唇口密封润滑不好和压力过低；会造成唇口密封摩擦阻力增大，磨损增加，缩短使用寿命，润滑油压力过低，会造成盾构机外部的泥沙进入唇口密封，损坏唇口密封，进一步进入刀盘轴承，引起轴承咬死，会使盾构无法掘进，所以盾构机中的集中润滑是一个非常重要的位置，同时，盾构机中的集中润滑是强制性的润滑。     

某型复合盾构刀盘的有限元静动态特性分析与优化

盾构刀盘受力情况的研究可以为盾构施工选型、刀盘的优化设计提供依据。文章在对盾构刀盘进行受力分析的基础上,利用ANSYS有限元分析软件对东莞地区某型大直径盾构刀盘进行了静力学分析,得到了在复合地层工况下盾构刀盘的应力与变形情况;对刀盘进行模态分析,得到了刀盘的振动特性;对刀盘结构进行优化改进,改善了刀盘的受力情况。结果表明,该型盾构刀盘在复合地层施工过程中刀盘最大应力为251 MPa,低于屈服极限345MPa;刀盘前6阶固有频率范围为38.803~64.842 Hz,满足强度和刚度要求,有利于在施工过程中控制地面沉降和保证施工的安全,同时也为隧道工程盾构选型提供了依据。     

复杂地质条件下盾构刀盘地质适应性分析

为了研究复杂地质条件下盾构刀盘的地质适应性,解决福州地铁盾构施工中遇到的问题,基于福州地铁4号线某区间工程实例,分析了该隧道工程的地质特性及区间内各类型地层与盾构刀盘的地质适应性,并对各地层中常出现的地质问题及应对措施进行探讨,提出区间内盾构刀盘进行地质适应性设计。经实践证明,该区间针对地质与盾构刀盘的适应性设计是合理可行的,可为类似工程提供参考。     

盾构隧道施工刀盘状态实时监测系统研制

盾构隧道施工中,由于盾构刀盘后面为有压舱,刀盘工作处于"黑箱"状态.为了实时监测盾构掘进过程中刀盘滚刀及刀盘整体的工作状态,研发了一套盾构隧道施工刀盘状态实时监测系统.该系统由传感器、控制与数据传输及算法与显示三个子系统组成;传感器子系统集成了自制的滚刀磨损量与转速传感器、温度传感器、数据采集模块和电源;集成的传感器安...     

某地铁隧道盾构机始发阶段地面塌陷原因分析

某地铁隧道在盾构机始发后的半个月内连续发生了三次地面塌陷.基于工程地质条件,结合地面监测资料和盾构机掘进时的运行状况,文章对这三次地面塌陷发生的原因进行了分析,并总结提出了盾构机始发过程中在各个方面应该注意的问题,以避免类似问题的发生.另外,文章也探讨了盾构法隧道施工工程地质问题与传统隧道施工工程地质问题发生机制的不同之处.     

盾构机不能推进的几种常见故障原因分析及处理方法

本文对由PLC控制的盾构机不能推进的几种常见故障原因进行了分析，并针对推进操作提出了处理方法。     

双电机驱动电动汽车动力参数选择及仿真分析

双电机驱动是提高电动车辆整车性能的有效方法,本文提出一种双电机耦合驱动系统的新构型;基于这种构型的特点,定义了双电机的4种驱动模式;依据车辆动力性要求计算出驱动系统各参数取值范围.根据双电机驱动系统的结构原理,提出基于门限值的模式切换控制策略;在Matlab/Simulink中搭建控制策略仿真模型,并与Cruise中整车模型进行联合仿真.仿真结果表明,这种新构型和控制策略在满足车辆动力性的前提下,可有效提高车辆的经济性.     

动力管道的应力分析及管壁厚计算

对管子在承受内压及自重时产生的应力进行了分析,对热力管道的强度校核公式及管子壁厚公式的选用作了简单的探讨。     

高低塔斜拉桥主塔承台优化及其结构计算分析

文章在对拟建南宁外环公路大冲邕江特大桥的自然条件、水文、地质、航道等因素进行分析研究的基础上,对原方案大桥主塔承台进行优化设计,并采用有限元软件建立全桥和局部有限元模型进行结构计算分析及验算,确定优化方案的合理性及可行性,为类似工程设计提供参考。     

A model for the visualization and analysis of elevator traffic

ABSTRACT

Analysis of elevator traffic in high rise buildings is critical to the performance evaluation of elevator group control systems (EGCS). Elevator dispatching methods or parking algorithms in an EGCS can be designed or modified according to analyses of traffic flow. However, interpretation of traffic flow based solely on numerical data may not be explicit and transparent for EGCS experts as well as for other non-expert building administration. In this study, we present a model for visualization and analysis of elevator traffic. First, we present an alternative approach for traffic analysis which we call route visualization. In the proposed approach, we initially decompose elevator traffic into its component parts and investigate each component independently. Then, using superposition of components we obtain a reconstructed model of overall traffic. This modeling approach provides component-based traffic analysis and representation of routes with intensities through data visualization. In the second part we introduce a multi-dimensional analysis of time parameters in ECGS. This approach provides a comparative analysis of several control algorithms such as dispatch or park algorithms for different combinations of traffic components.     

The changing face of parking-related data collection and analysis: The role of new technologies

Current trends in requirements for parking related information and in the availability of data are reviewed. Important influences include the increased need for data to assist in the efficient operation and management of parking stock and to assess the impact of parking on the local network and economy. New sources of data are described, particular attention being given to the availability of data as a byproduct of parking management systems and computerised enforcement systems. The use and performance of audio, video and data loggers in parking surveys is discussed as is the role of computers in questionnaire surveys. New methods of analysis involving spreadsheets, graphics and analysis software, links with databases and simulation models are outlined.     

基于Petri网的地铁信号系统可靠性分析

地铁信号系统是地铁系统的中枢神经,同时也是提高地铁运营水平的重要保障。在分析信号系统功能及故障类型的基础上,划分了设备重要度水平。通过地铁信号系统Petri网5大对象子类框架的搭建,分析研究了信号系统重要设备发生故障的情况下,系统各子类的动态Petri网可靠性模型。     

The planning and analysis of a new group rapid transit system: the SkyCabs monobeam system in Auckland

This paper examines a case study of the SkyCabs system as a way to alleviate some of the traffic problems of Auckland, New Zealand. SkyCabs is an elevated two-way monobeam carrying light eight-seater cabs on tracks on each side of the beam, available on demand, providing fast, pollution-free, unimpeded travel above the footpath with panoramic views of the city. The aim of this study is to investigate the attractiveness of implementing the SkyCabs system to and from Auckland central business district (CBD) and Auckland international airport by examining four variables: different routes, different number of stops/stations, different passenger demand levels, and different number of cabs in the system. The analysis utilizes geographical information system and simulation tools for the various scenarios considered. The results show that it is possible to assess the cost–benefit of alternative routes in terms of those four variables and rate of return on investment.     

A dynamic analysis of person and household activity and travel patterns using data from the first two waves in the Puget Sound Transportation Panel

Daily activity participation and travel patterns are examined using data from the Puget Sound Transportation Panel (PSTP), which contains two-pairs of daily travel diary information (wave 1 in 1989 and wave 2 in 1990). Summary data of the travel diaries at the person and household levels are obtained using cluster analysis. At the person level, four clusters are found reasonable for both activity and travel. The four-cluster solutions indicate substantial day-to-day variation in activity participation and similarity in travel behavior over time. Temporal changes are analyzed using contingency table methods and log-linear models. The analysis reveals that activity participation and mobility present many regularities over time. Transitions within each wave show strong dependence between two days for both activity and travel, with higher dependency for the travel patterns than for the activity patterns. These are consistent when the analysis focuses on a longer period such as a year. Temporal dependencies appear to be stronger in the household-based than the person-based analysis. A hierarchical structure is also found in the relationship between activity and travel clusters. The link between activity and travel is much stronger within a day, weaker from one day to another, and the least strong from one year to the next. Important irregularities, however, are found and may be due to scheduling time-frames adopted by the respondents that are only partially captured in the data used.     

滨州至德州高速公路单桩竖向抗压静载试验分析与计算

利用桩基自平衡测试方法的试验结果,结合桩基设计规范,分析了黄泛平原地区桩基承载力的受力特点与影响桩基承载力的主要因素。试验与分析结果表明,黄泛平原地区第四系冲积物以亚砂土、亚粘土夹粉细砂为主,多层结构居多,上层多为粘性土。此种工程地质条件下,影响桩基竖向承载力因素较多,特别是桩基施工质量与桩基混凝土浇筑对桩基竖向承载力影响较大。     

Integration of signal timing estimation model and dynamic traffic assignment in feedback loops: system design and case study

This paper presents an integrated framework for effective coupling of a signal timing estimation model and dynamic traffic assignment (DTA) in feedback loops. There are many challenges in effectively integrating signal timing tools with DTA software systems, such as data availability, exchange format, and system coupling. In this research, a tight coupling between a DTA model with various queue‐based simulation models and a quick estimation method Excel‐based signal control tool is achieved and tested. The presented framework design offers an automated solution for providing realistic signal timing parameters and intersection movement capacity allocation, especially for future year scenarios. The framework was used to design an open‐source data hub for multi‐resolution modeling in analysis, modeling and simulation applications, in which a typical regional planning model can be quickly converted to microscopic traffic simulation and signal optimization models. The coupling design and feedback loops are first demonstrated on a simple network, and we examine the theoretically important questions on the number of iterations required for reaching stable solutions in feedback loops. As shown in our experiment, the current coupled application becomes stable after about 30 iterations, when the capacity and signal timing parameters can quickly converge, while DTA's route switching model predominately determines and typically requires more iterations to reach a stable condition. A real‐world work zone case study illustrates how this application can be used to assess impacts of road construction or traffic incident events that disrupt normal traffic operations and cause route switching on multiple analysis levels. Copyright © 2014 John Wiley & Sons, Ltd.     

道路交通事故分析及预防对策

道路交通事故的预防是一个系统工程,通过对全国和新疆道路交通安全现状与道路交通事故原因的对比分析,分别从影响道路交通安全的人、车、路及环境四个方面提出了降低和预防道路交通事故的发生,确保行车安全的相应措施和建议。     

三峡右岸地下电站主厂房系统爆破开挖程序及开挖方法研究

主厂房系统爆破开挖程序和开挖方法,最直接地影响着整个工程工期、质量、安全及成本。如何结合工程具体特点,确定最优的爆破开挖程序和开挖方法,这是主厂房系统爆破开挖的关键所在。三峡右岸地下电站主厂房系统爆破开挖程序及开挖方法的研究成果,可供有关单位参考。