Greater Detail: GRADING and STORMWATER Flashcards
Line type used for existing contours
dashed
interval labeled on uphill side
Line type used for proposed contours
solid
interval labeled on uphill side
FFE
TW/BW
TC/BC
TS/BS
Finished floor elevation
Top of Wall / Bottom of Wall
Top of Curb / Bottom of Curb
Top of Stair / Bottom of Stair
*all will include a spot elevation
BF
HP/LP
TF or RE
INV. EL
Bottom of Footing
High Point / Low Point
Top of Frame or Rim Elevation
Invert Elevation
*all will include a spot elevation
CB
DI
MH
AD
Catch Basin
Drain Inlet
Manhole
Area Drain
*all will include top of frame and invert elevation (except for area drains, which only requires top of frame)
CIP RCP CMP VCP PVC
Cast Iron Pipe Reinforced Concrete Pipe Corrugated Metal Pipe Vitrified Clay Pipe Polyvinyl Chloride Pipe
*all will include a pipe size
PL
CLL
CL
Property Line ____ __ __ ____
Contract Limit Line ____ __ ____
Center Line ____ _ ____
- center lines will include a flow direction
CF to CY
divide by 27
SF to SY
divide by 9
Cut / fill calc. that is best for linear construction (roads, pathways, utility trenching)
METHOD:
Take cross sections at a certain interval, calculate areas of cut and fill for each section, average the areas of all sections taken and multiply that area by the length
Average End Area
Cut / fill calc. that is best for large but relatively simple grading plans
May be used to calculate volumes of water in a pond / lake
Establish no cut / no fill line, measure SF area of cut and fill for each contour within the no cut / no fill line, calc. total cut and fill, multiply by the contour interval
Contour Area Method
Cut / fill calc. that is best for complex grading projects and urban conditions
Overlay a grid over the area to be regraded, calculate the average change in cut / fill per cell by determining the average difference in elevation of all 4 corners, add average cut and fill together and multiply by the area of one grid cell
Borrow Pit Method (aka Grid Method)
The final grade after all landscape development has been completed; top surface of planted areas, pavements, etc. Normally designated by contours and spot elevations on a grading plan
Finished Grade
Top of the material on which the surface material (topsoil, pavement + base layers, etc) is placed. Subgrade is represented by the top of a fill situation and the bottom of a cut excavation.
Subgrade
Subgrade that must attain a specified density
Compacted Subgrade
Indicates a soil that has not been excavated or changed in any way
Undisturbed Subgrade
Imported material placed beneath pavements (usually course or fine aggregate)
Base / Subbase
Usually the elevation of the first floor of a structure; may also be used to designate the elevation of any floor
Finished Floor Elevation
The process of removing soil
Proposed contours extend across existing contours in the UPHILL direction
Cut / Cutting
The process of adding soil
Proposed contours extend across existing contours in the DOWNHILL direction
Fill / Filling
Fill material that is imported to the site
Borrow
The densification of soil under controlled conditions, particularly a specified moisture content
Compaction
Normally the top layer of a soil profile; may range in thickness from 1” - 1’-0” or greater.
Has a high organic content and is therefore subject to decomposition and is not an appropriate subgrade material for structures
Topsoil
Problem soils / conditions as it relates to construction (6)
- Loose silts
- Soft clay
- Fine water-bearing sands
- Soils with high organic content (e.g. peat)
- High water table
- Bedrock