1. SAB 3122 CONSTRUCTION TECHNOLOGY AND ESTIMATING Excavation
Dr. Chai Chang Saar

2. EXCAVATION BULKING FACTOR BULKING FACTORS ARE AS FOLLOWS: NO.
TYPES OF SOIL
% INCREASE IN VOLUME 1.
Sand
10% 2.
Clay
20% 3.
Ordinary Earth
25% 4.
Rocks
50%

3. EXCAVATION
Calculation for each activity. If the activities are missing, contractor will experience loss.
EXCAVATION ACTIVITIES
Excavation from formation level to foundation depth level.
Excavated soil taken out.
Dispose of excess earth from site.
Backfilling and compaction.
LABOUR CONSTANT USED IN CALCULATION

4. EXCAVATION 4 stages Site clearance Excavation – m3 hedges – m
bushes, shrubs – m2
cutting down trees – no
Excavation – m3
Supporting & strutting
By hand
Machinery/plant
Rental machinery
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5. EXCAVATION WORKS Bulking (disposal) – m3 Backfilling – m3 By hand
Lorry
Backfilling – m3
Excavated material
Imported material
Leveling with hardcore
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6. SITE CLEARANCE
Cutting down tress exceeding 600mm and n.e 900mm girth at 1.00m above ground level and grubbing up their roots and filling voids left by removal of roots with material arising from excavation – No
General worker
RM40/day
Sawing machine (Rental)
RM35/day
5 tonne lorry (Rental)
RM300/day
Cutting down trees
5 nos/day
3 general workers to cut down trees
3 general workers to remove
Profit 20%
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7. SUPPORT & STRUTTING Figure 1.1 Typical timbering in hard soils
Typical timbering in firm soils

8. SUPPORT & STRUTTING Figure 1.3 Typical timbering in dry loose soils
Typical timbering in loose wet soils

9. SUPPORT & STRUTTING
Assumption:
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10. SUPPORT & STRUTTING Assumption: Trench = 20.00m Carpenter = RM 60.00
General = RM 40.00
Timber = RM /tonne (1.40 m³)
Nail = RM 4.50/kg
Nail = 0.10kg/m² of gross supporting area
Timber usage = 15 times
1 Carpenter and 1 General Worker to cut & fix in output 2.25hr/m³
1 General Worker to remove in output 2.25hr/m³
Allow 10% wastage for timber work
Allow 20% profit and overhead
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11. EXCAVATION BY HAND
Labour constant for excavation by hand
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12. EXCAVATION BY HAND Adjustment for non-common soil excavation
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13. EXCAVATION BY HANDS
Built-up rate must consists of material, machinery and labour costs
Material & machinery cost
Excavation do not required material cost
Excavation by hand, therefore no machinery cost incurred
Labour cost
Labour constant for trench excavation not exceeding 2.00m = 4 hours/m3
Assumption:
Build up rate for 1m3 trench excavation, starting from reduced level, and maximum depth not exceeding 2.00m
Allow 20% Profit & overhead
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14. EXCAVATION BY MACHINERY
To get the rate for excavation using machinery, have to find out the excavator output, adjustment and excavator’s running cost
Excavator output
Loader (m3)
Average output(m3/hr) 8 ⅜ 9 12 18 1 25
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15. EXCAVATION BY MACHINERY
Type of soil
Multiplier
Sand
X 1.00
Clay
X 1.25
Soft rock
X 1.50
Rock
X 4.50
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16. EXCAVATION BY MACHINERY
Excavator’s running cost
Type (loader) m3)
Diesel/hr (litre)
Lubricator/week (litre)
4.00
9.00 ⅜
5.00
12.00
6.00
14.00
7.00
16.00 1
18.00
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17. EXCAVATION BY OWN MACHINERY
Build up rates for excavate oversite to reduce level maximum depth not exceeding 1.00meter by using own excavator ½ m3.
Assumption:
Average working days = 200days
Operator = RM 50.00/day
Life-cycle = 5 years
Diesel = RM 1.70/litre
Lubricator = RM 20.00/litre
Loan interest = 10% per year
Maintenance = 10% of purchase price for whole lifecycle
Transportation to site = 5% of purchase price for whole lifecycle
Scrap Value = RM 8,000.00
Excavator purchase price = RM 150,000.00
Allow 20% Profit & overhead
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18. EXCAVATION BY RENTAL EXCAVATOR
Build up rate for 1m3 trench excavation, starting from reduced level max depth not exceeding1.00m by using rented excavator.
Assumption
Using a ⅜ m³ excavator
Rental RM300.00/day (inclusive mobilize to site)
Diesel RM 1.70/litre
Lubricator RM 20.00/litre
Operator = RM 50.00/day
Allow 20% Profit & overhead
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19. DISPOSAL
% of bulking after the excavation (disposal)
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20. DISPOSAL BY HAND
Labour output for loading, hoisting and storing – 1.50hr/m3
Labour output for loading, hoisting, storing, spreading and leveling – 2.00hr/m3
Build up rate for removing 1 m3 excavated material 50.00m distance.
Assumption :
Excavated material = common soil, 25% bulk
Loading, hoisting and storing only
Allow 20% Profit & overhead
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21. DISPOSAL BY LORRY Lorry Loader (m3) Diesel/hr (lt) Lubricator/wk (lt)
1 tonne
0.80
3.50
0.50
5 tonne
3.25
6.00
1.00
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22. DISPOSAL BY LORRY
Build up rate for removing 1m3 excavated material and deposit in heaps 5km distance.
Assumption:
Lorry 5 tonne rental= RM /day (inclusive driver)
Speed = 30km/hr
Loading time: 10 mins
Unloading time: 5 mins
Common soil, bulking 25%
Diesel = RM 1.70/litre
Lubricator = RM 20.00/litre
Allow 20% Profit & overhead
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23. FILLING WITH EXCAVATED MATERIAL
Build up rate for 1m3 filing to excavation with material arising from excavation.
Assumption
Labour constant 0.75 hr/m3
25% of compaction and wastage
Allow 20% profit & overhead
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24. FILLING WITH IMPORTED MATERIAL
Build up rate for 1m3 filling to excavation with ordinary earth obtained off site.
Assumption:
Imported earth = RM 15.00/m3 (inclusive delivery to site)
25% of compaction & wastage
Labour constant 0.75 hr/m3
Allow 20% Profit & overhead
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25. Exercise
Excavation and Dispose
Conversion

26. Thank You