drawing. Refer to the example in figure 3-5, and readthe following explanation:1. STATION NUMBERS. The station numbersare lettered horizontally below the profile and grade lineand are centered on the appropriate vertical grid line.2. ELEVATIONS. At the bottom of the sheet, theprofile and grade-line elevations for each station arelettered vertically. The grade-line elevations are letteredjust above the profile elevations. Any station numbersother than full stations are noted as plus stations,vertically, just outside the bottom border.3. CUTS AND FILLS. Above the profile andgrade-line elevations are lettered the cuts and fills. Theyare also in a vertical position. The grade points, orpoints where the profile crosses the grade line, are alsonoted in this row. They are designated by the wordGRADE lettered vertically above the grade-pointstation.4. DITCHES. The procedure for dimensioningditches has two steps as follows:a. First, draw extension lines from the ends ofa ditch or any point in the ditch where the ditch gradechanges. These lines should be extended downward, anddimension lines (with heavy arrowheads) should bedrawn between them. These extension and dimensionlines should be drawn heavier than normal so they maybe distinguished from grid lines.b. Next, above the dimension line, letter theinformation necessary to describe the ditch. If thelettering is crowded, you may also use the space belowthe line. You should furnish the following information:percent of grade of the ditch, depth relative to centerline, type of ditch, and width of ditch. Give the elevationand station at the ends of the ditches and at changes ofgrade.5. VERTICAL CURVES. Each vertical curve onthe grade line is also dimensioned. Draw extension linesupward from the PVC and PVT. Then draw a dimensionline between the extension lines and letter the length ofthe curve above. Letter the station and elevation of thePVC, PVI, and PVT vertically over these points andabove the dimension line.6. CORRELATION WITH PLAN. All points onthe profile and grade line coincide with center-linepoints on the plan. For example, you should show thebeginning and ending of construction on the plan viewand also on the profile and grade line. Also, note theelevations at these points.7. DRAINAGE STRUCTURES. Dimension alldrainage structures, such as pipes and culverts, by notes.Note the station number, size of opening, length of pipe,and flow-line elevation.8. TITLE. In this example, the title, “PROFILEAND GRADE LINE is lettered below the ditchdimensions. Below this are noted the horizontal andvertical scales.SEQUENCE OF CONSTRUCTIONIn constructing a road, the construction crewsshould follow a specific sequence. First, they clear thearea through which the road must pass of trees, stumps,brush, boulders, and other debris. The width of theclearing varies greatly but is always at least 12 feetgreater than the roadway width; that is, the crew shouldclear at least 6 feet behind the construction limit on bothsides of the road.The next step is the grading operations and thelaying of cross-drain pipes, or culverts. The gradingoperations are carried on by the Equipment Operatorsuntil the subgrade is completed. In fill areas, the gradingis brought up in layers and compacted. In cuts, theexcavation is carried on until the subgrade elevation isreached, and then the earth is compacted. Throughoutthis step of the road construction, workers place theculverts when and where required. These culverts areplaced in their appropriate positions and at the requiredslopes according to the roadway plans.After the subgrade is completed, EquipmentOperators place abase course on the subgrade. The basecourse material can be gravel, sand, crushed stone, ormore expensive and permanent materials. Finally, theEquipment Operators place a surface course over thebase. This material can be sand, asphalt, blacktop,concrete, or similar materials.In some cases, traffic may be allowed to travel overthe subgrade itself. In others, traffic may require only agravel or stone surface. A high-speed road, however,requires abase and a hard, durable surface.SECTIONSAs you should recall from your study of the EA3TRAMAN, a section is a view of an object that has beencut by a plane that is perpendicular to the line of sight.For road sections, the line of sight is perpendicular tothe roadway center line.Sections are used for a variety of purposes duringthe various phases of road design and construction. Onepurpose is to define what the materials and design3-7
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