Achieving political acceptability for new transport infrastructure in congested urban regions

This paper analyzes the efficiency and political acceptability of road pricing and infrastructure policies targeted at relieving urban congestion. It combines a stylized transport model of an urban road network with a model of the political process that incorporates interactions between voters, citizen interest groups and politicians to explore the possibilities to reach political acceptability for efficient transport policies. In a numerical illustration, the paper compares a set of pricing and investment policies in terms of efficiency and acceptability. The illustration shows how conflicting interests can lead to non-efficient policies being chosen.     

北京局集团公司“三港三区域三品类”货运增量对策

在“公转铁”机遇带动下,北京局集团公司将货运增量重点由煤炭转向“三港三品类”,进行运力资源倾斜。分析“三港三区域三品类”货运量、装车卸车,从运输价格、运距结构、运力匹配、装卸车组织、环保政策、路企双方设备能力等方面分析货运增量影响因素,提出“三港三区域三品类”货运增量对策,即:增强货运市场营销策略积极参与市场竞争、加强运输组织释放“三港、三区域”运能、调整作业方案实现效率提升、依托“公转铁”政策支持优化运输结构、落实专用线扩能改造助力货运上量,提升“三港三区域三品类”市场竞争力,满足货运增量需求,实现北京局集团公司货运量持续增长。     

How to road price in a world with electric vehicles and government budget constraints

In this paper we examine what characterizes second-best road prices targeting external costs from driving electric (EV) and conventional (ICEV) vehicles when there are distortionary labor taxes and binding government budget constraints. Further, we examine how this second-best pricing fits with government set goals of reducing CO₂ emissions. The paper further develops an analytical framework for assessing first- and second-best road prices on vehicle kilometers, extending it to include EVs and externalities that vary geographically and by time of day. We find that optimal road prices largely vary with external cost, but are also significantly affected by the interactions with the rest of the fiscal system. Not surprisingly, the highest road prices should be for ICEVs in large cities during peak hours due to high external costs. More surprisingly, we find that the road price for ICEVs in rural areas should be lower than that for EVs due to large fiscal interaction effects. These road prices give large welfare gains, but they lead to no reduction in carbon emissions when applying the currently recommended social cost of carbon.     

Assessing potential likelihood and impacts of landslides on transportation network vulnerability

As one of the devastating natural disasters, landslide may induce significant losses of properties and lives area-wide, and generate dramatic damages to transportation network infrastructure. Accessing the impacts of landslide-induced disruptions to roadway infrastructure can be extremely difficult due to the complexity of involved impact factors and uncertainties of vulnerability related events. In this study, a data-driven approach is developed to assess landslide-induced transportation roadway network vulnerability and accessibility. The vulnerability analysis is conducted by integrating a series of static and dynamic factors to reflect the landslide likelihood and the consequences of network accessibility disruptions. The analytical hierarchy process (AHP) model was developed to assess and map the landslide likelihood. A generic vulnerability index (VI) was calculated for each roadway link in the network to identify critical links. Spatial distributions of landslide likelihood, consequences of network disruptions, and network vulnerability degrees were fused and analyzed. The roadway network on Oahu Island in Hawaii is utilized to demonstrate the effectiveness of the proposed approach with all the geo-coded information for its network vulnerability analysis induced by area-wide landslides. Specifically, the study area was classified into five categories of landslide likelihood: very high, high, moderate, low, and stable. About 34% of the study area was assigned as the high or very high categories. The results of network vulnerability analyses highlighted the importance of three highway segments tunnel through the Ko‘olau Range from leeward to windward, connecting Honolulu to the windward coast including the Pali highway segment, Likelike highway segment, and Interstate H-3 highway segment. The proposed network vulnerability analysis method provides a new perspective to examine the vulnerability and accessibility of the roadway network impacted by landslides.     

清石黄河大桥引桥施工

介绍了清石黄河大桥引桥的施工方案。对于桥墩比较高且没有预制场地进行主梁预制的桥梁施工,该方案可以降低成本,缩短施工周期。     

软基处理技术在辽宁省滨海地区废弃盐滩中的综合应用

本文通过辽宁省滨海公路大连市金州北海至葫芦套段七顶山盐场废弃盐滩软基处理的施工,总结了抛石挤淤、堆载预压、强夯置换等软基处理方法在滨海地区软基处理中的综合应用、施工工艺、质量控制手段和质量检验方法。     

沥青路面最大剪应力分析

采用ABAQUS软件对典型半刚性基层沥青路面及桥面铺装层中最大剪应力影响因素及变化规律进行了计算与分析。分析表明：半刚性基层沥青路面与水泥混凝土桥面铺装层最大剪应力分布与变化规律基本一致,在相同荷载条件作用下,最大剪应力水平亦接近;最大剪应力与车辆垂直荷载和水平荷载作用呈正比关系,最大剪应力受其影响显著;最大剪应力随着面层或铺装层厚度、模量的增加而相应地变小,随着半刚性基层厚度与模量的增加而变大。以上抗剪影响因素及变化规律的研究为解决车辙问题提供了一定的理论基础。     

浅析萨达里亚河大桥钻孔灌注桩施工控制

阐述了新疆维吾尔自治区喀什至叶城公路钻孔灌注桩施工方案和工艺控制措施。     

国外环境协调型多孔水泥混凝土道面的研究应用

对生态水泥混凝土的概念和分类进行了阐述,并对其在国外的研究应用情况及配合比组成进行了综述。     

橡胶改性沥青混合料技术研究

研究了目前橡胶改性沥青的主要两种加工方法,在分析橡胶沥青改性机理的基础上,指出橡胶沥青在道路建设中既能改善道路的路用性能,又具有降低行车噪音、增加行车舒适度和安全性的作用,而且既节约能源又环保,经济社会效益显著提高,值得大力推广。