MappingMapping

• Required readings: 18-1 to 18-10 &18-12&18-14, 18-16 and 18-17

• Required figures: 18-2, 18-5, 18-6, 18-7, 18-8, 18-10, and 18-12

Mapping• Hard and soft-copy maps• Importance for engineers: planning

locations, design facilities, and estimate quantities.

• Main types: topographic, cadastral, natural resources, facilities, land use, and construction

• Cartography: the overall process of map processing.

• Scale: large > 1in:100ft, small < 1in:1000ft

Map Production• Computer-aided drafting (CAD):

• Knowing point coordinates, using a software a map could be drawn, plotted, and transmitted.

• Contour lines are automatically generated from TIN. If desired, cross sections could be established and volumes could be computed.

• Some CAD systems designed to export data from total stations

• Manual drafting.

Map Components• Border: 1 in on the left side, 1/2 on the rest.• Coordinate system: marked along the border, and TIC

marks across the map.• Scale: ratio, equivalence, or graphic (the best).

• North arrow.• Legend: explain the symbols.• Title: at lower right corner, state: map type, project name,

location, date, scale, and contour intervals.• Notes.

Map Drawing• Planimetric details: compute the coordinates

of the points and draw them with respect to the TIC marks.

• Contours: first interpolate between known elevations, then connect the required elevations. Interpolation is done by: estimation, proportion, or other techniques.

• Contour intervals in meters at scales:

0.5 at 1:500 1 at 1:1000 2 at 1:2000

5 at 1:5000 10 at 1:10,000