Pavement stakeout will depend on the type of paving equipment used. Steps in the method commonly used for paving concrete highways are as follows:

1. Set a double line of steel side forms, equipped with flanges that serve as tracts for traveling paving equipment.

2. Fill the space between the forms with concrete poured from a concrete paving machine (commonly called just a paver).

3. Spread the concrete with a mechanical spreader that travels on the flanges of the side forms.

4. Finish the surface with a finisher, a machine that also travels on the side forms.

The line-and-grade problemthat is, the layout or stakeout problemconsists principally of setting the side forms to correct line with the upper edges of the flanges at the grade prescribed for the highway. If the finished grade shown on the plans is the center-line grade, then the forms are set with tops at the center-line grade less the crossfall. If the design elevations are shown for points other than those on the center line, the form elevation is related to the design points as indicated by the typical section.

Stakeout maybe done by setting a line or lines of offset hubs, as previously described. Some-times, however, a line of hubs is driven along the line the forms will occupy and driven to grade elevation less the depth of a side form. The forms are then set to the line and the grade by simply placing them on the hubs.

Concrete paving is also done by the slip form method in which, instead of a complete double line of forms, a sliding or traveling section of formwork is an integral part of the spreading and finishing machinery. The machinery is kept on line and the pavement finished at grade by a control device or devices. The line control device usually follows a wire stretched between rods that are offset from the pavement edge.

Forms are not usually used in asphalt paving. Asphalt paving equipment, in general, is designed to lay the pavement at a given thickness, following the fine-graded subgrade surface. The manner in which a given piece of equipment is kept on line varies, and the stakeout for equipment varies accordingly.

A STRUCTURAL survey is one that is part of the chain of human activities that will bring a structure, such as a building, a bridge, or a pier into existence.

As when a highway is built, the first major step in the construction of a structure is usually the rough gradingthat is, the earthmoving needed to bring the surface of the site up to, or down to, the approximate specified rough grade. The stakeout for rough grading is commonly done by the GRID method. The area to be graded, which is shown, along with the prescribed finish grade elevation on the site or plot plan is laid off in 25-, 50-, or 100-ft grid squares. The elevation at each corner point is determined; the difference between that and the prescribed grade elevation is computed; and a grade stake is marked with the depth of cut or fill; then the stake is driven into the ground at the point.