SBS改性沥青碎石封层质量控制与施工技术要点分析

SBS改性沥青同步碎石封层因具有较强的防水性和耐磨性,以及良好的抗老化性能和抗反射裂缝能力等优点,近年来被广泛应用于沥青路面的预防性养护中。本文结合S314线SBS改性沥青碎石封层施工现场情况,对SBS改性沥青碎石封层的施工质量控制、施工工艺与技术要点等进行了分析。     

橡胶沥青同步碎石封层施工技术研究

橡胶沥青同步碎石封层具有良好的防水性、防滑性和耐久性,处理路面裂缝效果显著,经济环保效益突出。本文结合橡胶沥青同步碎石封层技术在青海东部地区干线公路病害处治工程中的应用情况,对其施工工艺和控制要点进行了详细论述,以期为该技术在青海省的推广应用提供借鉴。     

同步碎石下封层层间粘结性能影响因素研究

为提高半刚性基层沥青路面的使用寿命,文章通过制备"基层+透层+同步碎石下封层+沥青下面层"复合结构试件,采用斜剪试验研究同步碎石下封层层间抗剪强度,分析试验温度及材料组成对同步碎石下封层层间粘结性能的影响规律。结果表明:层间粘结性能随试验温度的升高显著下降,尤其低于45℃时表现明显;采用SBS改性沥青作封层油时粘结性能明显优于基质沥青,但温度提高时两者抗剪强度差值减小;沥青用量和集料撒布率增加时层间粘结性能先上升后下降,分别在用量1.6 kg/m~2和撒布率70%时效果最好,集料粒径增加时层间粘结性能则逐渐下降。     

高速公路路面下封层沥青碎石同步技术分析

在路面工程中作为一种关键技术,路面下封层沥青碎石同步技术应用效果好坏会影响到路面通车安全性与质量,所以为了满足公路建设需求,通过结合实际,以路面下封层沥青碎石同步技术为研究背景,对该技术的实践要点进行分析。在下封层项目开展时,需要严格地按照沥青同步技术的原则进行施工且对设计的工程参数进行控制,如此才能满足高速公路路面建设需求。     

同步沥青碎石封层技术在路面养护中的应用

文章以广西河池公路沥青路面养护工程项目为例,针对该公路路面已发生的病害问题,从原材料的选取、施工前期的准备、同步沥青碎石封层施工及施工工艺的控制管理等方面,探讨同步沥青碎石封层技术在路面养护中的应用,为公路预养护工程提供参考。     

同步碎石封层技术在沥青路面大修工程中的应用

同步碎石封层既能够用于道路养护,又可以用于道路重建,在我国沥青路面养护与大修工程中应用广泛。文章分析了同步碎石封层的作用,探讨了同步碎石封层施工技术方法的优越性,并结合新G357融水至和睦(现S204线K25+000～K35+500段)沥青路面大修工程为例,探讨了同步碎石封层施工技术应用要点,以期为类似工程实践提供参考。     

橡胶沥青同步碎石封层施工技术探讨

橡胶沥青同步碎石封层具备抗老化能力强、黏弹性好、节约资源、耐久性好、施工效率高等特点,可以让路面防水损害能力得到较大程度的提高。以某高速公路项目为例,深入研究了橡胶沥青同步碎石封层在高速公路的施工工艺,具有一定的参考价值。     

橡胶沥青碎石封层在路面养护中的应用研究

为研究橡胶沥青碎石封层性能影响因素,探讨其在养护工程中的应用效果,文章结合正交试验设计方法,进行了直剪试验与单轴贯入试验,分析了橡胶沥青洒布量、碎石撒布量及碎石加热温度对橡胶沥青碎石封层性能的影响,并对其应用效果展开分析。结果表明:随沥青洒布量及碎石撒布量的增加,橡胶沥青碎石封层的抗剪强度与极限破坏荷载出现先增大后减小趋势,且随碎石加热温度提高封层性能提升明显,因此在制备橡胶沥青碎石封层时应结合旧路面现状与沥青、碎石用量进行设计。现场检查结果显示,该封层可有效提高沥青路面的抗滑性能与密水性能。     

同步碎石封层技术在公路养护中的应用

文章基于同步碎石封层技术的概念原理及利用效果,阐述了同步碎石封层技术的优势,并以241国道桂林段养护工程为例,介绍了同步碎石封层施工技术在公路养护中的施工方法及质量控制措施。     

沥青路面养护中如何加强同步碎石封层技术

通过结合某公路沥青路面养护工程实例,针对该公路沥青路面已发生的病害,采用同步碎石封层施工技术进行养护施工,并从原材料选择、施工准备阶段、作业技术要求、施工现场工艺控制、施工质量管理五大方面进行深入研究,以加强同步碎石封层施工技术,可为同步碎石封层施工技术在沥青路面养护工程中的应用提供参考。     

Analysis of factors affecting the choice of route of pedestrians

Pedestrians as compared to vehicular traffic enjoy a high degree freedom of movement even in heavily congested areas. Consequently, there are more alternative links available to pedestrians between a given origin‐destination (O‐D) pair. This paper describes a study done by the University of Calgary to evaluate the factors affecting the choice of route on intra‐CBD trips or trips within the Central Business District (CBD).

An origin destination survey conducted in downtown Calgary, Alberta enabled the identification of the most significant factors influencing the choice. These factors were analyzed in relation to the physical characteristics of the location, personal characteristics of the trip maker and the type of the trip.

It appears that most people chose the shortest link and factors such as the level of congestion, safety or visual attractions were only secondary. This suggests that the length should be made a major consideration when planning and designing pedestrian links.     

注汽管道承压能力评估和实物试验验证

基于失效评估图技术对某注汽管道进行了承压能力评价,给出了管线在不同腐蚀壁厚情况下的极限承压能力和极限裂纹尺寸。并利用实物爆破试验验证了评价方法的安全性和有效性,通过对爆破断口进行宏观和微观分析,发现管段的开裂属于脆性开裂。     

实现多组态计量软件集中监控的可行性分析

天然气自动计量系统有多种组态软件,由于软件的不相通性,造成了计量系统数据采集的通用性差、数据传输与入库的时效性差、数据利用的可靠性低.结合各组态软件的实际情况,从设计上充分利用Oracle大数据处理能力以及Partition(分区表)的特性,实现历史数据的存储,应用WebService与COM+数据访问组件提供多层数据访问架构,采用OPC与DDE工业数据交换协议,实现了各站场计量数据的实时上传,为连续数据采集和实时监控提供了可能,节约了改造成本.     

Non-parametric analyses of efficiency of airports

This paper estimates the efficiencies and productivity changes of 12 international airports in the Asia-Pacific region based on data from 1998 to 2006. We apply stochastic frontier analysis (SFA) to compute efficiency estimates and use the Malmquist productivity index (MPI) to analyze productivity changes. We use the SFA model with a translog-type production function after testing the statistical hypotheses. According to the results of the SFA hypothesis tests, airports have experienced a technological regression; the deviations from the efficiency frontier are caused more by technical inefficiency than random noise. However, the inefficiency was found to decrease. The MPI reveals a declining trend resulting more from technological change than from efficiency change, with a decrease in inefficiency. Taken together, both the hypothesis tests and the MPI not only provide consistent conclusions, but also suggest that airports should concentrate on technological progress.     

波纹管应力分析研究进展

评述了波纹管应力理论研究方法的进展情况，围绕解析法、工程近似法和数值法，对波纹管理论研究中的一些主要成果作了较详细的回顾和总结，对各种研究方法作出了评价，展望了亟待解决的一些问题。     

埋地管道防腐保温层失效评价

明确埋地管道防腐保温层的技术评价标准,对埋地钢质管道的安全运行,延长管道使用寿命具有重要意义。为了对埋地管道防腐保温层做出有效评价,从间接检测与开挖检测2个方面,结合现场检测数据,提出了基于防腐保温层的电流衰减率、绝缘电阻率、质量状况与厚度的分级评价标准及基于4种评价指标的综合评判方法。工程实践表明,该评价标准对防腐保温层是否存在失效能做出有效判断。     

城市轨道交通杂散电流监测系统概述

介绍了城市轨道交通工程中杂散电流不同的监测系统的构成,分析了集中式、分散式和智能型等监测系统的配置和功能,以及智能型实时在线监测系统的重要意义,为轨道交通工程杂散电流监测系统的选择与应用提供参考。     

Preliminary results of an analysis of areas of influence in Shanghai

The main deficiency of most current modeling approaches to transportation can be identified as neglect of the integration of existing geographical knowledge in regard to the ex ante transport/land use modeling approaches, with its focus on territorial dynamics and theory development. This paper addresses this aspect of the problem by introducing a theoretical and methodological framework for the analysis of the interrelationship between land uses. The analysis attempts to determine to what extent the functional land use in a city can be considered an ordered pattern. The order sought does not rely on purely spatial configurations, but on the correlation of transportation and land use. The first section of this paper focuses on theoretical considerations. It stresses the fact that conventional approaches do not apply in the present context. It then suggests an alternative based on areas of influence and measured in terms of level of attractance of land uses. The second describes a procedure based on this alternative following the remarkable contribution of Hanjoul, Beguin and Thill. An application of this procedure to the analysis of Shanghai is then examined. Finally, an evaluation of the strategies for optimizing the interrelationship between land uses is presented. The paper concludes with a possible research agenda.     

输油管道中原油乳状液的流变性研究

原油乳状液的流变性是原油开采后在管道中输送的重要研究方面,为了更好地研究这一性质,采用电动搅拌机、偏光显微镜以及流变仪等仪器来测定不同含水率的原油乳状液在不同条件下的黏度,观测不同含水率的原油乳状液在偏光显微镜下的形态。并且分别对原油乳状液的黏度与含水率之间的关系以及与剪切速率之间的关系进行研究,初步确定了所测区块原油乳状液的转相点以及该区块原油乳状液的流变特性,为生产中的油气集输提供了理论依据。     

Direct analysis of the perceived importance of attributes of reliability of travel modes in urban travel

Reliability of travel modes was found to be the most important characteristic of transportation systems in several attitudinal investigations of individual travel behavior. This paper represents the first part of a research effort aimed at gaining a better understanding of the characteristics of reliability of transportation modes in urban travel. In this research, reliability characteristics are identified; their importance relative to each other is assessed, and an insight into possible structure of an objective reliability index is discussed. The research is based on perceived values of reliability, which were identified through a large attitudinal survey conducted in the Chicago metropolitan area.