地铁车站主体与公路桥共建设计及附属工程一体化设计方案研究——以北京轨道交通房北线四环路站为例

地铁车站建筑设计需考虑规划条件、市政道路条件、地下管线资料及周边环境条件等因素,从可实施性、功能性、经济性等方面进行系统比选来确定最优方案。随着城市发展对地铁车站建筑设计要求的提高,车站建筑设计与城市发展的融合性越来越受到重视,然而传统的设计方法过多考虑了控制因素,限制了车站建筑的主动性和灵活性。以北京轨道交通房山线北延工程四环路站为例,在充分结合周边控制因素及规划条件的前提下,提出车站与桥梁共建及附属一体化设计思路。结果表明:(1)地铁车站主体与规划公路桥在竖向可实现共建设计,平面上实现共路由;(2)不同建设时序情况下,将地块分段实施,可实现车站附属与地块深度一体化开发。     

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。     

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.     

Traffic modelling in system boundary expansion of road pavement life cycle assessment

This paper uses a case study of a UK inter-urban road, to explore the impact of extending the system boundary of road pavement life cycle assessment (LCA) to include increased traffic emissions due to delays during maintenance. Some previous studies have attempted this but have been limited to hypothetical scenarios or simplified traffic modelling, with no validation or sensitivity analysis. In this study, micro-simulation modelling of traffic was used to estimate emissions caused by delays at road works, for several traffic management options. The emissions were compared to those created by the maintenance operation, estimated using an LCA model. In this case study, the extra traffic emissions caused by delays at road works are relatively small, compared to those from the maintenance process, except for hydrocarbon emissions. However, they are generally close to, or above, the materiality threshold recommended in PAS2050 for estimating carbon footprints, and reach 5–10% when traffic flow levels are increased (hypothetically) or when traffic management is imposed outside times of lowest traffic flow. It is recommended, therefore, that emissions due to traffic disruption at road works should be included within the system boundary of road pavement LCA and carbon footprint studies and should be considered in developing guidelines for environmental product declarations of road pavement maintenance products and services.     

利用CIVIL 3D进行海港工程疏浚设计方法研究

本文在南方某海港工程港池航道工程设计中引入BIM正向设计,利用CIVIL 3D建立了地形曲面和地质曲面模型,建立采样线,对地形曲面、设计曲面、地质曲面进行采样;用断面法进行疏浚工程量计算,用程序自带网格施工图及其他软件等多种方法进行校核以验证计算准确性;通过材质定义,计算不同土类疏浚量并在断面图中表示;在设计完成后,按...     

我国公共工程PFI融资模式项目风险管理研究

从PFI融资模式的基本内涵和运行机制出发,运用项目融资与风险管理等相关理论,对PFI项目风险进行了详细分析,并依据PFI项目风险的分担原则和机制,提出了应对我国PFI项目风险的管理策略及相关措施,以期对推进我国PFI项目健康、快速发展有所裨益.     

高精度水下导航定位技术在考古打捞中的应用

高精度水下导航定位技术已被广泛应用于水下工程.但在考古打捞中的应用还很少.结合某考古打捞工程,分析考古打捞的技术特点,阐述控制系统、使用设备、设备安装调试、作业过程、以及可能存在的主要问题等,全面介绍高精度水下导航定位技术在考古打捞中的应用.     

异形网箱生态结构的设计及应用

为保护落成洲整治建筑物头部潜堤根部及LL3~LL5号丁坝根部的现有植被,在标准网箱结构的基础上,研发出异形网箱结构来替代抛石筑堤。异形网箱生态堤在满足工程功能需求的前提下,完整保护了落成洲的原有生态环境,可为航道整治生态结构设计提供参考。     

Effect of Seismic Parameters on the Safety Factor for an Underground Cavern北大核心CSCD

In order to quantitatively evaluate the safety of the surrounding rock of an underground cavern under seis-mic load, a comprehensive evaluation method for the stability of surrounding rock is proposed based on the general safety factor and point safety factor. A calculation method for the general safety factor of a cavern based on the prin-ciple of shear strength reduction of a rock mass is given, the run-through of the plastic zone between the main power-house and main transformer room is presented as a critical criterion for the overall instability of the cavern, and the general safety factor is obtained by searching for the reduction coefficient. A point safety factor calculation method based on the Mohr-Coulomb yield criterion is given. The influence of different seismic input parameters on the general safety factor of the cavern and the point safety factor of key positions are studied based on an underground power-house cavern of a hydropower station in Southwest China. The results show that the quantitative evaluation method for the stability of the surrounding rock based on the safety factor is feasible and can reflect the general safety de-gree and local safety degree of different positions of the cavern for different working conditions. It is found that the general safety factor of the cavern and the point safety factor of key positions decrease with an increase of the ampli-tude and duration of a seismic wave while they increase with an increase of the incident angle; additionally, the low frequency of a seismic wave has a great influence on the cavern while the high frequency has little effect. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.