Grading involves modifying landforms to accommodate structures and ensure proper drainage. Key considerations for grading include utilities, contours, drainage, erosion control, and balancing cut and fill amounts. Grading goals are to prevent water entry, control runoff, and minimally disturb sites. Proper grading creates suitable, pleasing ground surfaces with positive drainage close to original levels. Spot elevations further specify grading, while defined areas require careful grading to drainage edges or make entire areas level. Cut and fill processes move earth to achieve required grading. Recommended gradients depend on use and terrain.

1. GRADING BASICS
• Grading is the process of modification of existing landform
to accommodate new structures, parking and circulation
and to ensure positive drainage.
Consideration must be given to utilities such as: water,
gas, power, communication services, and sewerage for
disposal of wastewater, and storm water.
• Grading process requires a careful change of contours so
that they support the integration of building with the site.

2. • The land may be graded or adjusted to suit the architectural or
engineering requirements, or the architecture may be adopted to
meet variations in the ground level so that the original surface is
disturbed the least.
• Extensive alterations in the landform may lead to unstable
conditions resulting in erosion, landslides, floods, and a complete
destruction of ecosystem.
IMPORTANCE OF GRADING

3. 1. The ground surface must be suitable for the intended purpose
or use.
2. The visual result should be pleasing.
3. The result of any grading must have positive drainage.
4. The grading plans should attempt to keep new levels as close
as possible to the original state of the land.
5. When ground is reshaped it should be done positively and at
the scale of the machinery.
6. Top soil must be conserved wherever possible.
7. The quantity of cut should be approximately equal to the
quantity of the fill.
PRINCIPLES OF GRADING
TECHNOLOGY

4. • Three principal goals in development
of a grading plan are:
– Keep unwanted water from
entering a building.
– Keep surface run off from
creating damage to property or
people during periods of heavy
rainfall and subsequent runoff.
– To accommodate the structure
on site with disturbing the site to
minimum.

6. GRADIENT
• Gradient refers to the changing elevation along the Earth's surface or the
rate of the slope.
• It is expressed in % or ratio or degrees.
– 1% slope = 100:1
– 10% slope = 10:1 =
• Percentage of slope is expressed as the number of meters (feet) rise in 100 m
(100 ft) of horizontal distance, typically referred to as rise/run.
• If the slope rises2 m (2 ft) in 100 m (100 ft), it is considered a 2 percent slope. The
percentage of slope can be calculated by the following formula:
• Where
D=vertical rise, mm (ft)
L=horizontal distance, mm (ft)
G = gradient, %

7. Elevation of point B=48 347 mm Elevation of
point A =47 463 mm
Vertical difference D=884 mm
Horizontal difference L= 35 357 mm
There fore:

8. SPOT ELEVATIONS
• Spot elevations provide additional information beyond that given by
the contour lines. They indicate Micro grading.
• Spot elevations are used to establish limits of slope, to locate contour
lines, and to provide detail for establishing control points that cannot
be obtained via contour lines.
• Typical locations for taking spot elevations are:
• Top and bottom of steps.
• Tops of retaining wall.
• Outside entrances to buildings.
• Inside floor levels of buildings.
• Corners of all structures.

9. GRADING FOR DEFINED AREA
• Slopes of less than about 2 percent in the open landscape appear flat to the
human eye. However, in areas adjacent to built structures, even the slightest
slope becomes noticeable because of the relationship of the grade to mortar
joints, roof lines and other level architectural features.

10. Perimeter Edge Level:
Figures schematically illustrate alternative methods for manipulating a surface
for drainage while allowing at least one peripheral edge to remain level.

13. • Entire Area Level:
Some circumstances, such as rooftop landscapes or enclosed courtyards, require that the
entire surface of the enclosed area be level.
Figure ahead illustrates two ways that an area can remain level and still drain properly by
the use of porous surface material, such as sand/gravel the use of individually elevated
Each case requires an adequate system beneath the pavers to carry required rainfall
effectively.

14. These alternatives are applicable to relatively flat surfaces as tennis courts and
other types of courts.

15. SCHEMATIC GRADING FOR OPEN
AREAS
• Preparing site grading plan
– Grading of a site should be thoughtful systematic process that begins with
an analysis and understanding of the site and ends with an overall
detailed Grading plan.
– Site Analysis:
Study the general lay of the land by using topographic maps and site
visits.
1. Determine high points, low points, ridges, and valleys.
2. Note natural drainage systems and directions of flow that exist on the
site.
– Site use concept:
Determine how existing landforms would affect proposed use areas, such
as building locations, roads, parking areas, walkways, plazas, and lawn
areas.

16. SITE ANALYSIS
(EXAMPLE)

17. CUT AND FILL
• The process of removal of earth from one part of site to achieve required grading
and the place and using the dug up earth to achieve required grading by filling it
at another place on the same sit.
• The amount of material from cuts roughly matches the amount of fill needed to
make nearby embankments, so minimizing the amount of construction labor.

18. Standards for grading around a typical building.

19. Surface drainage can be achieved by pitching surfaces to natural
drainage feature and systems.

20. Gradingto createberms. Berms can be created for noise and wind barriers or for additional soil
depth above unfavorable sub-grade conditions, such as a high groundwater table.

21. Gradingto createlevel areas. Relatively flat gradients are needed for sports fields,
outdoor terraces, and sometimes for areas near buildings.

22. Gradingto modifyexistinglandforms. Deep gullies, narrow ridges, or steep slopes can be
modified to create more useful and attractive landforms.

23. Gradingfor increasedsiteinterest. Grading can help emphasize a site's topography or
add interest to an otherwise flat site.

24. Grading related to good views.

25. Grading to expose vistas

26. Grading related to bad views.

27. Grading to fit structures to sites.

28. Grading to facilitate better plant growth

29. Grading to emphasize or control circulation.

30. RECOMMENED GRADIENTS

31. RECOMMENED GRADIENTS

32. Schematic grading for outdoor
basketball court

33. GRADING FOR STREETS AND ROADS
• The road has a constant slope and thus presents more problem.
• The function of the road is to serve as an path for vehicles and as an
adjunct to the drainage system.
• A road must be designed:
– in conformance to strict design standards, maintaining
appropriate grades, curvatures and sight distances.
– To minimize fluctuations across variable terrain.
– To have a constant slope or gradient.
– To provide shortest route possible.
– To minimize cut and fill.
– As far as possible parallel to the contour lines.