基于Web GIS的公路施工管理系统研究

基于Web从组织机构和功能两个方面分析公路施工管理系统的实际需求,分析公路施工管理系统中主要模块之间的关系,并据此设计基于Web的公路施工管理系统的总体结构。该系统利用GIS、图形显示等技术,为施工管理搭建了一个地图可视化平台,在电子图库、三维分析、工程量计算等方面进行了一定的探索。     

道路软土地区路基养护体系的完善探析

软土路基因其特殊的结构层,往往会给现场道路作业造成很大的困难,其破坏了原始路基的牢固性,进而导致道路整体发生裂缝或沉降.尽管施工单位制定了一系列的加固处理方法,软土路基依旧存在着各种质量问题.鉴于此,需要研究道路软土地区路基养护体系的完善措施,以使道路软土路段的性能得到进一步改善.     

辽阳出口路现场热再生简析

重点介绍了辽阳出口路现场热再生沥青混合料的级配设计和施工工艺及施工过程中的质量控制要点。     

Total dynamic response of a PSS vehicle negotiating asymmetric road excitations

A planar suspension system (PSS) is a novel automobile suspension system in which an individual spring–damper strut is implemented in both the vertical and longitudinal directions, respectively. The wheels in a vehicle with such a suspension system can move back and forth relative to the chassis. When a PSS vehicle experiences asymmetric road excitations, the relative longitudinal motion of wheels with respect to the chassis in two sides of the same axle are not identical, and thus the two wheels at one axle will not be aligned in the same axis. The total dynamic responses, including those of the bounce, pitch and the roll of the PSS vehicle, to the asymmetric road excitation may exhibit different characteristics from those of a conventional vehicle. This paper presents an investigation into the comprehensive dynamic behaviour of a vehicle with the PSS, in such a road condition, on both the straight and curved roads. The study was carried out using an 18 DOF full-car model incorporating a radial-spring tyre–ground contact model and a 2D tyre–ground dynamic friction model. Results demonstrate that the total dynamic behaviour of a PSS vehicle is generally comparable with that of the conventional vehicle, while PSS exhibits significant improvement in absorbing the impact forces along the longitudinal direction when compared to the conventional suspension system. The PSS vehicle is found to be more stable than the conventional vehicle in terms of the directional performance against the disturbance of the road potholes on a straight line manoeuvre, while exhibiting a very similar handling performance on a curved line.     

A novel fuzzy logic correctional algorithm for traction control systems on uneven low-friction road conditions

The traction control system (TCS) might prevent excessive skid of the driving wheels so as to enhance the driving performance and direction stability of the vehicle. But if driven on an uneven low-friction road, the vehicle body often vibrates severely due to the drastic fluctuations of driving wheels, and then the vehicle comfort might be reduced greatly. The vibrations could be hardly removed with traditional drive-slip control logic of the TCS. In this paper, a novel fuzzy logic controller has been brought forward, in which the vibration signals of the driving wheels are adopted as new controlled variables, and then the engine torque and the active brake pressure might be coordinately re-adjusted besides the basic logic of a traditional TCS. In the proposed controller, an adjustable engine torque and pressure compensation loop are adopted to constrain the drastic vehicle vibration. Thus, the wheel driving slips and the vibration degrees might be adjusted synchronously and effectively. The simulation results and the real vehicle tests validated that the proposed algorithm is effective and adaptable for a complicated uneven low-friction road.     

轨道交通车站地域的集中开发

透过在轨道交通车站地域城市开发集中的表象,发掘出它最终的导向是城市的集中发展。通过研究集中开发在城市用地、功能、空间集中方面蕴涵的积极意义,探索在这些方面各自集中的有效方式。除论证了车站地域开发与城市集中发展的因果联系之外,还给城市管理部门主动推进这一特殊领域的城市集中提供理论支持和技术参考。轨道交通车站地域的集中开发所带来的城市集中是全方位的,对城市整体用地、功能及空间集中都是一种积极的整合,因此是实现城市集中发展的一种切实有效的途径。     

内外温差对明挖隧道主体结构内力的影响研究

明挖隧道内外温差会使其衬砌结构产生附加应力,严重时会使隧道轴线方向的衬砌产生环向裂缝。通过对温度进行现场监测,获得工程实际内外温差,对其规律进行简要分析并将其作为有限元计算的温度边界条件;采用ANSYS进行有限元计算,考虑明挖隧道主体结构修建完成和回填完成两个阶段,对隧道内部温度低于外部温度、隧道内部温度高于外部温度以及无温差3种工况进行分析,得出温差对隧道结构应力的影响规律。     

北京地铁车站附属建筑的设置

以北京在建地铁4、5号线、10号线一期工程的规划设计、建设实践为基础,分析以往地铁车站附属建筑设置过程中容易忽视的几个细节问题,如车站出入口、通风亭、冷却塔与城市道路红线、建设用地及文物的关系,以及通风亭和冷却塔的建筑形式等。最后得出结论：地铁车站附属建筑设置应结合城市道路近、远期规划科学设置,满足城市道路交叉口渠化、人行道最小宽度要求。现状已实现规划的建设用地内尽量不安排车站附属建筑;位于城市待改造用地内,出入口、通风亭及部分通道应按临时建（构）筑物设计,待规划实施时,其改造方案可与建设项目统一设计;位于正在办理规划审批手续的建设用地内,车站附属建筑应与建设项目作一体化设计。旧城内车站附属建筑设计应做多方案比选,慎重抉择。环控专业应提早参与配合,设计前期应事先确定通风亭、冷却塔的建筑形式,以便预留合适的用地,做到及早控制。     

旧路改建工程设计

结合莞惠公路改建工程的设计经验,介绍改建公路设计时技术标准的应用,道路中线及路面结构的选择,阐述了如何进行加固和接长桥涵验算设计。