27-11-2012, 02:17 PM
ESTIMATING EARTHWORK
ESTIMATING.ppt (Size: 199.5 KB / Downloads: 700)
Earthwork includes:
1. Excavation
2. Grading: Moving earth to change elevation
3. Temporary shoring
4. Back fill or fill: Adding earth to raise grade
5. Compaction: Increasing density
6. Disposal
Job conditions
Material type
Water level and moisture content
Job size
Length of haul
Haul road condition (accessibility and load restrictions)
Management conditions
Equipment conditions and maintenance practices
Skills of work force and management
Planning, supervision and coordination of work.
CALCULATING EARTHWORK QUANTITIES
1. End Area Method
a. Take cross-sections at regular intervals, typically, 100’ intervals.
b. Calculate the cross-section end areas
c. The volume of earthwork between sections is obtained by taking the average of the end areas at each station in square feet multiplied by the distance between sections in feet and dividing by 27 to obtain the volume in cubic yards.