Till now you have learnt how to design horizontal curve and vertical curve. Creating cross sections include extracting elevations from ground surface, designing the assembly or template and applying it along the vertical alignment to get final cross sections and related quantities.
1. In this topic you will learn how to create cross section from ground surface data.
2. You can create cross sections irrespective of chainage interval you have set in Horizontal or Vertical alignment tabs. Click on “ Generate” button in cross section tab. Mention ‘chainage interval’, and ‘interval at curve’ values in cross section settings window.
3. You can generate ground values at specified distances by selecting “At Distance” option or you can generate the ground values based on where the cross section line intersects with the TIN which will show accurate ground profile by selecting “As ground” option.
If you want cross sections at points like the start of the curve, end of the curve, then selects check box “add chainages at station points”.
As per options we discussed, you can create cross section, but how long the cross section length to be? if you have points for long distance from the alignment line. To control the width of cross section ground values a concept called swath width is introduced.
If you want to consider widths up to the boundary as created in the “existing surface tab” select “Boundary” option. With this selection the cross section levels are generated up to the boundary on both the sides along the cross section.
Select the “fixed option” and enter the fixed width on left and right sides to set as swath width.
Select the “Variable” option to specify the required swath widths at each of the cross section or a range can be given so that the taper between the specified chainages will be automatically considered. This option, is extremely helpful when excel data is available to plot the Right of way (ROW).
If you want to create any remark while creating the cross sections from ground surface, respective alignment names to be selected for marking remark. Remarks get created in alignment and cross section intersection point and are reflected in respective cross section.
In case if you require to create custom cross sections at locations like cross drainage structures, bridges or any type of crossing, which are not matching with the distances as specified in standard interval you can create such cross sections in ESurvey CADD.
Click “Additional Button”.
Enter the chainages as required and close the additional Chainages window.