Line Stakes

Line (or alignment) stakes – Line (or alignment) stakes mark the horizontal
location of the earthwork to be completed and give the direction of the proposed construction. Running over stakes or otherwise damaging them before they have served their purpose results in many hours of extra work to replace them and delays the completion of the project.

Rough alignment stakes are placed far ahead of the clearing crew to mark boundaries of the area to be cleared and grubbed. These stakes, or markers, are not of a control nature and their loss is expected. On some stakes, the alignment information and the grade requirement are combined on the same stake, as shown in Figure 5-33.

Centerline Stakes – Centerline stakes are set along the center line of a project and are identified by letters, shown in Figure 34. Most stakes are marked on both the front and back.

On centerline stakes, the station number is written on the front of the stake, such as the 0 + 00, 1 + 00, 4 + 75, and 5 + 25 shown in Figure 35.

The required grade is always established at the center line of the project. The amount of change in elevation is written on the back of the centerline stake with a cut or fill symbol, which is known as the crowfoot, shown in Figure 36. The crowfoot is the reference point of the vertical measure or grade.

Shoulder Stakes – Stakes that are set on a line parallel, in the same direction and interval with the center line are called shoulder stakes and are identified by the symbol SH at the top of the stake, as shown in Figure 37.

Shoulder stakes mark the outer edge of the shoulders and are set with the broad side facing the center line of the road on the shoulder line. Shoulder stakes carry the same station number as the centerline stake to which they are set, but the station number is placed on the back of the stake, the side facing away from the center line. The amount of cut or fill is marked on the side of the shoulder stake facing the center line, the front, and represents the amount of cut or fill required at that location. The horizontal distance from the shoulder stake to the center line is sometimes placed beneath the cut-or-fill figure.

The basic difference between centerline stakes marked with the symbol and
shoulder stakes marked SH is (1) centerline stakes are set along the center
line of the project and (2) shoulder stakes are set parallel with the center line, defining the shoulder of the road or runway, and face the center line as shown in Figure 38.

Cut-and-Fill Stakes – Lowering the elevation of a grade is known as making a cut. Cut stakes are designated by the letter C written on the stake. The numerals following the letter C indicate the amount of ground to be cut to obtain the desired grade and are measured from the crowfoot down.

Raising the elevation of the ground is known as making a fill. A fill stake is
designated by the letter F written on the stake. The numerals that follow the
letter F indicate the amount of ground material needed to bring the existing ground to the desired grade and are measured from the crowfoot mark on the stake up.

In going from a cut to a fill or vice versa, there may be one or more stakes representing points on the desired grade, as shown in Figure 39. These stakes are marked with GRADE, or GRD and a crowfoot mark even with the
desired grade.

Basically, the difference in cut, fill, or on-grade stakes is as follows:

• Cut stakes indicate lowering the ground or elevation.
• Fill stakes indicate raising the ground or elevation.
• On-grade stakes indicate the ground is at the desired grade and does not need a cut or fill.

Offset Stakes – After a survey of a project has been completed and the stakes are set and marked, the required amount of work needed to complete the job is determined by using the information on these stakes. Since this information has to be used often during construction and the original stakes can be destroyed or covered up by carelessness or inexperienced operators, it is necessary to document this information.

To prevent the loss of reference information, transfer the required information from the stake located in the immediate area of construction to a new stake. Set this stake far enough away so that it will not be damaged or destroyed by equipment being operated in the construction area. This new stake is called an offset stake and is identified by the symbol OF or an O as shown in Figure 40.

You should note the number of linear feet that separates the offset stake from the original reference stake. This is written on the offset stake below the OF or within the circle, followed by the amount of cut or fill, in feet, which may be required. A stake marked OF 35’CL C-1° means that the stake is offset 35 feet from the centerline stake and that a cut of 1 foot is required to attain the desired final grade.

The difference in elevation must be noted on the offset stake. The symbol, representing the stake from which the information was originally transferred, is also noted on the offset stake. If the offset stake is offset from a shoulder stake, the symbol is SH instead of CL.

The amount of cut or fill, if any, must be noted on the offset stake. However, because of existing terrain, this information on the offset stake may not be the same as that on the original stake. In Figure 41, you can see that the offset stake reads for a cut to be made to reach a desired elevation at the center line, while a centerline stake would be marked for a fill to reach the same elevation.

Slope Stakes – The identification markings on slope stakes may vary according to survey parties, the symbol SS is the most commonly used slope stake symbol. The information normally found on a slope stake, shown in Figure 42, is any cut or fill requirements, the distance from the center line, and the slope ratio. When it becomes necessary to offset the slope stake, the offset distance from where the slope stake should be is written at the bottom of the offset stake. Slope stakes indicate the intersection of the cut-or-fill slope with the existing natural groundline and limit of earthwork on each side of the center line shown in Figure 43.

Right-of-Way Stakes – Stakes set on the property line of a construction site are known as right-of-way stakes. These stakes mark the boundaries of the site or project. You must not operate equipment outside the property line defined by the right-of-way stakes. The right-of-way stakes are usually marked by with colored cloth, called bunting, or flagging. Occasionally right-of-way stakes may be marked with the symbol R/W shown in Figure 44.

Finish Grade Stakes – When performing final grading, you are likely to work with stakes called blue tops. These are hub stakes which are usually 2 inches by 2 inches by 6 inches. These hubs are driven into the ground until the top is at the exact elevation of the finished grade as determined by the surveying crew. They are colored with a blue lumber crayon, or keel, to identify them as finish grade stakes. Red crayon is normally used to indicate the subgrade elevation. Blue top stakes are placed when the existing grade is within 0.2 feet, or 2.4 inches, above the final or desired grade. The desired  grade is obtained by lowering or raising the compacted grade with a grader until it is flush or even with the top of the hub, as shown in Figure 5-45.