Research And Implementation Of Road Cross Section CAD System

Road cross section design is an integral part of road design, and account for a largeproportion, heavy and repetitive, if done by manual, very tedious and error-prone. Therefore,the application of CAD technology, to improve the quality and efficiency of road crosssection design has the very vital significance.In the case of understanding the development of road cross section CAD system,drawing the rich experience of the design institute, on the basis of its road CAD applicationdevelopment for many years, merging the advantages of domestic and foreign similarsoftware, the paper designed to develop a new generation of road cross section CAD systemcarefully. In this paper, several key technologies of the system ware studied deeply,including cross section automatic design, modified design, earthwork calculation andallocation etc.Supporting the transition to subgrade cross section design is proposed for cross sectionautomatic design; based on the determination of subgrade cross section, according to therelation of subgrade edge elevation, ditch top elevation and canal top elevation to determinethe type, number and sequence of the component outside subgrade, and then calculate thespecific parameters of each component on the basis of the cross section ground line data.Finally, three strategies is used to optimize and improve the quality and aesthetic of crosssection automatic design. For the ease and efficiency of cross section design, basing onmessage mechanism is proposed to cross section modified design, all messages is generatedautomatically by the system, the stake, which is wrong, can be located by the message andmodified, can also bulk modifications. A number of methods are provided for calculatingthe cross section area and the number of earthwork, adapting to differentsituations.Semi-automatic deployment of visualization is used for earthwork allocation,achieving the deployment of separating subgrade across the design line and intuitivedeployment of crossing ramp within the scope of interoperability, the plan and vertical section can be selected for displaying the graphic of road route.According to the methods above, the road cross section CAD system developed reducethe workload of staff, improve the efficiency, easy to use, and close to the actual work.