桥上CRTSⅡ型板式无砟轨道台后锚固体系端刺结构受力变形特性

通过在高速铁路正线上开展长期温度荷载下的原位监测和列车制动荷载下的实车试验,以及运用ABAQUS有限元软件的数值计算,进行高速铁路桥上CRTSⅡ型板式无砟轨道倒T型和Π型台后锚固体系的端刺结构在温度力和制动力作用下的受力变形特性研究。结果表明:在降温和升温过程中,端刺结构周围土体压应力较大值主要出现在主端刺摩擦板的下部和桥台方向首个小端刺的位置,端刺结构变形主要以顶部弯拉为主,整体纵向变形较小;在紧急制动荷载的作用下,钢轨纵向应力、端刺纵向位移均随着轴重的增加而明显增大,但端刺纵向位移绝对值较小,与温度荷载作用相比,紧急制动荷载作用对端刺结构的影响小。     

浅谈高速铁路长大隧道应急通信

介绍了高速铁路长大隧道中的应急通信实现方案;提出了高速铁路中其他几种常用应急组网方式;对应急通信系统中的现场、基站/车站、指挥中心等相关设备进行了简单介绍。     

集装箱专用平车加装承载板实现滚装运输技术研究

为弥补应急情况下滚装运输所需平车数量缺口,同时为完善车辆自身应急保障能力,分析集装箱专用平车用于滚装运输需求,针对集装箱专用平车用于滚装运输存在的主要问题,提出在不改变车体结构前提下,通过加装承载板实现滚装运输的解决思路。结合集装箱专用平车结构特点,分析承载板的数量、尺寸、材质,设计承载板由承载面、横支撑架、渡板、斜支腿、受力面、绳拴构成,给出加装改造方法,并通过校核承载能力和研究适运范围,研究加装改造后的集装箱专用平车滚装运输能力,得出改造后的集装箱专用平车可以满足大部分滚装运输货物运输需要。     

Effects of shadow evacuation on megaregion evacuations

Transportation systems serve important roles during emergencies, in particular for evacuations. However, efficient travel during these life-and-death scenarios can be adversely impacted by external conditions, such as unnecessary and unneeded travel. This research sought to enhance the understanding of the effects of these conditions by analyzing shadow evacuations, and their impact on regional traffic operations in megaregions, more broadly. The research was based on simulations of a range of hurricane evacuation threat scenarios in the Gulf of Mexico building upon prior study using TRANSIMS. These assessments are also targeted at what many assume could be worst case evacuation conditions and pushing the limits of current simulation modeling capability. Among the broader findings of this work was that shadow evacuation participation rates did not significantly impact the evacuation clearance times within mandatory evacuation areas of the megaregion as long as demand could be temporarily spread out. This finding does not, however, suggest that the shadow evacuations have no impact on evacuation processes. High rates of shadow evacuees can cause significant congestion if they are not able to exit critical routes before mandatory evacuees reach areas further away from the coast.     

Locating emergency vehicles with an approximate queuing model and a meta-heuristic solution approach

In this paper, the location of emergency service (ES) vehicles is studied on fully connected networks. Queuing theory is utilized to obtain the performance metrics of the system. An approximate queuing model the (AQM) is proposed. For the AQM, different service rate formulations are constructed. These formulations are tested with a simulation study for different approximation levels. A mathematical model is proposed to minimize the mean response time of ES systems based on AQM. In the model, multiple vehicles are allowed at a single location. The objective function of the model has no closed form expression. A genetic algorithm is constructed to solve the model. With the help of the genetic algorithm, the effect of assigning multiple vehicles on the mean response time is reported.     

常用应急抢险装备的合理选择和配备

我国自然灾害频发,地震、洪水、泥石流等灾害极容易对道路,房屋等建筑造成巨大的损坏,从而对抢险过程直接或间接地增加了难度。为了高效遂行抢险任务和提高抢险能力,就有必要提高处理交通基础设施的能力。而抢险设备的选择和合理的配置能够大大提高抢险任务效率。一方面,对于不同的抢险任务,有着不同的作业内容,其中所需要的抢险器械也各不相同。另一方面,同一种工程机械又有着不同的型号,各自又具有独特的技术性能和适用范围。一种机械可以完成多种作业,而一种作业又可以使用多种工程机械。因此如何对工程机械的选择以及合理的配置是本文的重点。     

Large-scale evacuation network optimization: a bi-level control method with uncertain arterial demand

To improve the efficiency of large-scale evacuations, a network aggregation method and a bi-level optimization control method are proposed in this paper. The network aggregation method indicates the uncertain evacuation demand on the arterial sub-network and balances accuracy and efficiency by refining local road sub-networks. The bi-level optimization control method is developed to reconfigure the aggregated network from both supply and demand sides with contraflow and conflict elimination. The main purpose of this control method is to make the arterial sub-network to be served without congestion and interruption. Then, a corresponding bi-objective network flow model is presented in a static manner for an oversaturated network, and a Genetic Algorithm-based solution method is used to solve the evacuation problem. The numerical results from optimizing a city-scale evacuation network for a super typhoon justify the validity and usefulness of the network aggregation and optimization control methods.     

重型汽车低附着路面制动稳定性的仿真研究

文章利用trucksim重型汽车动力学仿真软件,对六轮双轴重型汽车在低附着路面左右车轮附着系数不一致情况下进行紧急制动的行驶工况进行了仿真研究.研究结果表明在低附着路面进行紧急制动时,对制动轮进行制动压力控制,有ABS控制的重型汽车比没有ABS控制的重型汽车具有更好地行驶稳定性.但在低附着路面上,有ABS控制的重型汽车...     

隧道紧急停车带流场和局部阻力数值模拟

基于N-S方程和k-ε湍流模型,采用CFD方法对隧道内风压、风速场进行了数值模拟及计算分析,得到了隧道纵向气流流动规律、速度和压力分布规律,计算出了隧道紧急停车带的局部阻力系数。与试验结果相对比,数值模拟结果与试验结果非常吻合。     

加筋格宾挡墙在怀化至通道（湘桂界）高速公路避险车道中的应用

加筋格宾挡墙作为一种新型的柔性支挡结构,因其环保性能突出,应用前景广阔。结合怀通高速公路工程实例,介绍了加筋格宾挡墙的工作原理、技术特点、施工步骤,并采用Macstars2000软件对其稳定性进行了分析计算。