Greater Detail: GRADING and STORMWATER Flashcards Preview

LARE SECTION 4 > Greater Detail: GRADING and STORMWATER > Flashcards

Flashcards in Greater Detail: GRADING and STORMWATER Deck (142)
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1

Line type used for existing contours

dashed
(interval labeled on uphill side)

2

Line type used for proposed contours

solid
(interval labeled on uphill side)

3

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

4

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

5

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)

6

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

7

PL
CLL
CL

Property Line ____ __ __ ____
Contract Limit Line ____ __ ____
Center Line ____ _ ____

* center lines will include a flow direction

8

CF to CY

divide by 27

9

SF to SY

divide by 9

10

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

11

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

12

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)

13

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

14

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

15

Subgrade that must attain a specified density

Compacted Subgrade

16

Indicates a soil that has not been excavated or changed in any way

Undisturbed Subgrade

17

Imported material placed beneath pavements (usually course or fine aggregate)

Base / Subbase

18

Usually the elevation of the first floor of a structure; may also be used to designate the elevation of any floor

Finished Floor Elevation

19

The process of removing soil

Proposed contours extend across existing contours in the UPHILL direction

Cut / Cutting

20

The process of adding soil

Proposed contours extend across existing contours in the DOWNHILL direction

Fill / Filling

21

Fill material that is imported to the site

Borrow

22

The densification of soil under controlled conditions, particularly a specified moisture content

Compaction

23

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

24

Problem soils / conditions as it relates to construction (6)

1. Loose silts
2. Soft clay
3. Fine water-bearing sands
4. Soils with high organic content (e.g. peat)
5. High water table
6. Bedrock

25

When soils become unconsolidated due to excavation, scraping, removal of vegetation etc

Erosion

26

Most effective strategy for minimizing erosion

Reduce area to be disturbed

27

TESC Plans

Temporary Erosion and Sedimentation Control Plans

Soil erosion and sedimentation control plans may be required by code to be submitted prior to start of construction

28

Methods of erosion control (2)

1. Strip and stockpile existing topsoil to avoid unnecessary loss (to be replaced after regrading is complete)

2. Grading should be informed by the erosion tendency of the site’s soil (increasing length and degree of slope will increase erosion potential)

29

If balance of cut and fill cannot be met is it better to have more cut or more fill

CUT

- less costly to export soil than to purchase and import soil

- cut subgrade / finished grade is more stable and erosion resistant than filled subgrade / finished grade

30

RIDGES (and roadway crowns) Point ___

(Contour signature)

Downhill