Title: Earthworks
1Earthworks Mass DiagramsClay Blackwell MDT
- Welcome
- Child 1 2
- Hailey
- Hunter
2Agenda
- Purpose Review Earthwork principles and
understand the use of Mass Diagrams. - General Plan Use the lecture to review
earthwork mass diagram principles and implement
them into daily design and construction
procedures. - Objectives Participants should understand
shrink, swell, haul, and the use of the Mass
diagram to accomplish standard engineering tasks
without the use of a Lawyer.
3Why is Dirt so important?
4Some Want A Little
5Many Want More
6And Some Dont Care (Walleye Wiss)
7And Many Died For It
8Overview
- Banked Volume
- Compacted Volume
- Shrink
- Swell
- Earthwork Elements
- Mass Haul Diagrams - Terminology
- Mass Haul Diagrams Field Examples
9Banked Volume
- In Place In Situ
- Undisturbed
10Compacted Volume
- Manipulate
- Crush
- Add Water
- Mix
11Contractor-Inspector Compaction Issue. Job went
smooth after resolution.
12Shrink
- Compacted Volume less than the Banked Volume.
- Clay, Silt, Sand.
13Swell
- Compacted Volume Greater than the Banked Volume.
- Rock
14Adjustments To Excavation
- Unclassified Excavation
- Should the following adjustments be added or
deducted from the roadway excavation quantity?
15Approach Excavation?
- Should be Added
- Usually included in the roadway quantities.
- Approach embankment should be measured at the
project completion and earthworks report edited
to provide a true shrink/swell for future
information.
16Structure Excavation?
- Added
- Usually not included in roadway Excavation.
Minute on large Construction projects. - Be careful on small earthwork projects set up
for borrow. - Select Backfill
17Pavement Removal?
- Deducted
- If the material is recycled and not used in the
subgrade. - No adjustment needed if incorporated into the
fill as its already included in the staked
quantity.
18Topsoil Stripping?
19Roadway Obliteration?
- Deducted if not economical and practical to
haul or use. - Added if economical and practical to use.
20Sub excavation?
- Added if suitable
- Deducted if unsuitable. Less excavation will
be available for fill since suitable excavated
material will be needed to fill the sub excavated
void.
21Mass Haul Diagram Terminology
- Cut
- Excavation a positive value
- Fill
- Embankment a negative value
- Embankment Plus an adjusted volume due to
shrink or swell. - Mass Ordinate
- Algebraic sum of the cut and fill.
- Haul
- There are two references haul. Haul refers to
the distance excavated material is moved or the
technical version of a distance volume
(station-yard). - Balance Line
- The cut is equal to the fill.
22Mass Ordinate
- The Algebraic sum of the accumulated cut or fill.
- The cut will be a positive value.
- The fill will be negative.
- This is the vertical scale on a mass diagram.
- Where the mass ordinate changes signs, between
these two stations a balance point exists.
23Mass Ordinate, Shrink Factor 1.00
24Mass Ordinate, Shrink Factor 1.32
25Mass Ordinate Graph
26Haul
- Haul is computed by multiplying the volume of
excavation removed from its original position by
a mean distance. Km m3 or station yd3. - The distance between the center volume of
excavation and the center volume of embankment is
the average haul distance. - Haul influences the cost of earthwork.
- Haul is only the cost to transport.
27Scraper Productivity
28Redneck Haul
29Haul Estimate
30Average Haul
31Haul vs. Waste/Borrow?
32Child 3,4, 5 Hannah, Heather, Hudson
33Mass Diagrams
- Grading Summary and the Mass Haul Diagram are the
contractors primary tools for bidding earthwork. - Representation of the way the dirt should
probably be moved on a project. - Determines where additional work may be needed
with respect to grades and alignment. (Designer
Field) - If gross earth movements contradict the mass
diagram Red Flag. Investigate Document. - Usually a very good tool for dispute resolution.
- Opinion- One of the most important documents in
a set of plans. Earthwork in most cases is the
major cost on a project. The diagram usually
represents the quality of a set of plans.
34Mass Diagram Characteristics
- A rising mass curve denotes cut.
- A falling mass curve denotes fill.
- Steep slopes of a the curve indicate heavy cut or
fill vs. flat slopes which indicate small
earthwork quantities. - Points of zero slope on the mass diagram show
change from cut to fill or fill to cut. - If a horizontal line intersects the curve at two
points the cut and fill are in balance or equal.
35Profile Mass Diagram
36Haul Limits
37Mass Diagram 1(Plan)
38Mass Diagram 1 (Staked)
39Mass Diagram 1 (As-Built)
40Mass Diagram 2 (Plan)
41Mass Diagram 2 (Staked)
42Borrow Entrance-Haul Comparison Mass Diagram 2
43Mass Diagram 3 (Plan 32 Shrink)
44Mass Diagram 3 (25 Shrink)
45Mass Diagram 4 (Plan)
46Mass Diagram 4 (Staked)
47Mass Diagram 4 (As-Built)
48Mass Diagram 5 (Plan)
49Mass Diagram 5 (Staked)
50Mass Diagram 5 (As-Built)
51Mass Diagram 5 (Theoretical)
52Summary
53Child number 5 (Hudson)
54(No Transcript)