基于累积损伤因子的水泥混凝土路面设计(英文)

考虑荷载疲劳应力和温度疲劳应力的综合疲劳方程,计算了单轴单轮及单轴双轮轴载的覆盖通行率,利用累积损伤因子替代标准轴载在交通量换算中的作用,提出了直接计算各级轴载对路面结构总的累积疲劳损伤方法和新的水泥混凝土路面设计方法,并采用两组交通量对轴载累积损伤量的计算方法的准确性与可行性进行了验证。分析结果表明:公路横断面上各点处轴载的作用次数是不同的,各级轴载的累积疲劳损伤峰值不一定在同一位置,利用基于累积损伤因子的水泥混凝土路面设计方法计算得到两组交通量下路面的最不利位置厚度均为22cm,符合设计要求,其他位置厚度可按累积损伤曲线相应减小,此设计方法避免了现行规范基于标准轴载和疲劳耗损等效原则的水泥混凝土路面设计方法与路面实际损伤中存在的差异及轴载换算方法的局限性。     

高速公路改扩建桥涵外业勘察要点

结合沈铁高速公路的特点,着重介绍了桥涵外业勘察的重点内容,为高速公路的改扩建设计提供有利的设计依据。     

高速公路波形梁护栏损坏状态及维修方法探讨

波形梁护栏在我国高速公路上运用广泛且损坏频繁,通过大量调查研究,分析了波形梁护栏的损坏状态以及现有的波形梁护栏维修方法及适用条件,指出波形梁护栏立柱维修常用方法中存在的一些不规范操作,为护栏维修积累经验。     

GPS在高速公路工程施工测量中的应用

GPS（Global Positioning System）全球定位系统是美国研制并在1994年投入使用的卫星导航与定位系统,该系统已被广泛使用。重点介绍GPS-RTK在湖北宜巴高速公路松林坡大桥桩基测量中的应用,并根据实践总结了GPS-RTK在施工测量中的注意事项。     

Assessing the accuracy of the Sydney Household Travel Survey with GPS

Over the past few years, GPS has been used in a number of surveys in the US to assess the accuracy of household travel surveys. The results have been somewhat alarming in that most of these exercises have shown that the standard trip-based CATI survey conducted in the US under-reports travel by about 20–25%. It was decided to use GPS to assess the accuracy of the Sydney Household Travel Survey, a continuous survey conducted by face-to-face interviewing. The procedure used was for the interviewers to recruit households for the household travel survey in the normal manner, and then, if the household met certain criteria, to endeavour to recruit the household to also undertake a GPS survey. A small sample of about 50 households was obtained, and GPS devices successfully retrieved that measured data on the same day as the travel diary was completed. In addition, participants in the GPS survey completed a prompted recall survey a week or two later, using maps and tabulations of travel obtained from the GPS devices, to identify mode, purpose and occupancy for trips measured by the GPS, and also to check for accuracy in defining trip ends and total number of trips. Based on the analysis of the GPS compared to the diary results, it was found that respondents under-reported their travel by about 7%, which is much less than in the US CATI results. Respondents were also found to under-report travel distances and over-report travel times. There was also a high incidence of non-reporting for VKT.

基于位移连续的静力损伤识别

为减小采用挠度法对桥梁结构进行静力损伤识别时识别结果出现误判的可能性,从位移连续条件出发对桥梁结构建立损伤识别模型,通过使理论计算挠度值逼近实测值,同时使节点相对转角最小,提出位移连续静力损伤识别法,然后利用多目标最优化方法求解。以简支梁为例对该方法的准确性进行验证,结果表明:该方法综合考虑了挠度与相对转角2个位移连续性条件,与实际情况更接近,在一定程度上降低了损伤误判的可能性。     

Numerical study of damage potential in buildings due to excavations

Evaluation industrial factory building damage potential due to ground movements caused by excavations inside the building is a critical design consideration when reconstructing the underground equipment of the industrial factory building. In this paper,the behavior of a support system for a reconstruction project of underground equipment of the industrial factory building in Shanghai and its effects on a pile-foundation supported building are presented. The 8.1 m deep excavation is made through soft clay to...     

自动驾驶仪系统在航测机中的应用及故障处理

航测机为高质量地完成航拍和重力测量任务,把飞行员从繁重的飞行操纵中解脱出来,需要在飞机上安装自动驾驶仪系统,使飞机在自动驾驶仪的控制下完成定高和定向飞行。阐述APS-65自动驾驶仪系统的组成、功能和特点,对航测机上安装APS-65自动驾驶仪系统过程中遇到的问题进行分析,并提出处理措施。     

基于大理市个体旅游交通行为分析

通过问卷调查的方式,获得大理市旅游交通的基础数据,采用统计分析的方法,得出系统客观的实证研究成果。在抽样调查的基础上,通过考察旅游者自身属性、出行信息以及与出游相关因子,运用量化的方法对所得结果进行分析,从而得出基于个体的旅游交通行为一般规律。     

沈大高速公路路面车辙病害原因分析

本文通过对沈大高速公路路面车辙破损的调查,阐述车辙产生的原因,方便在今后设计、施工中进行预防,并延长高速公路的使用寿命。