CE 453 Lesson 23
Courtesy of Dr. David Carlson, Agronomy at Iowa State University
Earthwork Analysis
• Average End Area Method
• Consideration for shrinkage
• Balance line Considerations
•
Limit of Freehaul (LFD)
•
Limit of Profitable Haul (LFH)
CUT
FILL
Conversion for CY
27
Shrinkage factor =
1.25
Mass
Station End Area End Area Vol.
Vol.
Adjusted Diagram
Cut (xx^2)Fill (xx^2) Cut (xx^3)Fill(xx^3) Fill(xx^3) Ordinate
0
40
0
0
333.333 37.037 46.2963
1
140
20
287.037
555.556 83.3333 104.167
2
160
25
738.426
407.407 261.111 326.389
3
60
116
819.444
Mass Diagram
Net Cumulative Volume (C.Y.)
1000
800
600
400
200
0
0
1
2
3
4
-200
-400
Station
Series1
5
6
7
Special Terms
• Free haul distance (FHD)- distance earth is
moved without additional compensation
• Limit of Profitable Haul (LPH) - distance beyond
which it is more economical to borrow or waste
than to haul from the project
• Overhaul – volume of material (Y) moved X
Stations beyond Freehaul, measured in sta – yd3,
or sta- m3
• Borrow – material purchased outside of project
• Waste – excavated material not used in project
Mass Diagram Development
• 1) Place FHD and LPH distances in all
large loops
• 2) Place other Balance lines to minimize
cost of movement (theoretical)
• 3) Calculate borrow, waste, and overhaul in
all loops
• 4) Identify stations where each of the above
occur
Mass Diagram
Net Cumulative Volume (C.Y.)
1000
800
600
400
200
0
0
1
2
3
4
-200
-400
Station
Series1
5
6
7
Mass Diagram
1000
Over Haul
Net Cumulative Volume (C.Y.)
800
600
FHD
400
200
LPH
0
0
1
2
3
4
-200
-400
Station
5
6
7
Second, Larger Example
Mass Diagram
10000
Net Cumulative yardage
8000
6000
4000
2000
0
-2000 0
-4000
10
20
30
LPH
-6000
-8000
FHD
-10000
-12000
Stations
40
Mass Diagram
10000
Net Cumulative yardage
8000
6000
4000
FHD
2000
0
-2000 0
-4000
10
20
30
LPH
-6000
-8000
-10000
FHD
-12000
Stations
40
Mass Diagram
10000
8000
preferred balance line
Net Cumulative yardage
6000
FHD
4000
2000
0
-2000 0
-4000
10
20
30
LPH
-6000
-8000
-10000
FHD
-12000
Stations
40