1. Lecture 3 - Excavation
Objectives:-
1. To learn the excavation work, backfill and
removal of surplus soil.
2. To relate the excavation works as per
clauses in SMM2
3. To determine the various clauses applied
to the excavation works.
Outcomes:-
1. Able to differentiate the different clauses
used
2. Able to write down the dimensions clearly.

2. A single storey house with pad
footings.
Foundation (Footing)
Ground level
Resistance from the soil.
Loading from the house

3. So to construct a house what do
we need?
 1. A foundation, in this case this a a pad
footing.
 2. So we need to determine first the type
of foundation designed by the engineer.
 3. Each type of foundation may not involve
the same type of excavation activities.
 4. Each activity may use different types of
machineries or method of excavation.

4. Clause D.12.6. Excavation pit
for footing
Section of footing Plan of footing
Footing
Stump
Excavation depth
Plan dimension
a
b

5. A three-storey building with pile
foundation Clause D.12.8 page 18
Ground level
Pile cap
R.C. pile
Stump
Hard strata

6. Excavating for pile caps and
trenches for ground beams
Ground beams
Stump
Pile cap
R.C. pile

7. Summary of excavation work:-
 1. To measure excavation work we must
first determine the type of excavation
work.
 2. With the type of excavation determined
find out which clause to be used.
 3. Using the clause now you could
determine next the dimensions of
excavation.

8. Disposal of excavated material
Clause D17 to D22 page 19 & 20
On site
Off site
Boundary of construction site

9. Filling Clause D.23 to D.34 page 20
& 21
Filling material
Column stump
RC footing

10. Classification of filling material
Clause D.23
 1. Materials arising
from the excavation
 The material that is
suitable for filling.

11. 2. Materials that is to be treated
or selected
 1. Material to be
filtered and to be
separated from those
unsuitable material
like rubbish, timber
and stones.
 2. It involves more
time, labour and of
course more
expensive.
Sieve
Treated material

12. 3. Material obtained off-site
 1. Material from the
excavated site is not
suitable.
 2. Material for backfill
to be purchased from
other sources, like
imported earth,

13. Exercise no. 1- Measure the excavation
work to the footings (F1)
Plan of a brick wall ( 3 nos.)

14. How to write down the answer?
 First find out the type of foundation from
the drawing.
 Then search for the relevant clause in
SMM2.
 Then find out the unit of measurement.
 Also find out any other conditions
necessary.

15. How to write down the answer?
To do that we need to know what type of work involved.
So we need more information about this structure

16. The structure
THE ELEVATION
With these two additional diagrams we can now
understand the structure and know the construction
method.

17. So how many items we need to
measure?

18. Find out the excavation depth first.

19. Description
 1. What type of activity?
 Excavate pit for brick wall foundation.
 2. From what level?
 From ground level.
 3. To what depth?
 Need to find out, and classify according to
clause D.10
 4. Anything else?
 Check clauseD.12.6 again.

20. Description
 Lets put it all together:-
Excavate pit for brick wall
foundation commencing from
ground levels with depth not
exceeding 2.00m. ( 3 nos.)

21. Write this in your taking off paper
 Excavate pit for brick
wall foundation
commencing from
ground levels with
depth not exceeding
2.00m. ( 3 nos.)
First write down the description

22. How to write down the answer?
Depth of excavation:
1125
50
1175
Length of foundation:
Width of foundation:
Then you need to provide side cast or
workings
Description

23. Your answer
Side cast/working
 Excavate pit for brick
wall foundation
commencing from
ground levels with
depth not exceeding
2.00m. ( 1 no.)
L
W
D
m3
3/

24. Measure the excavation work again
based on the following:-
 1. Another brick wall with foundation F2 (5
nos.) with the same layout but the depth
(d) is now 3.05m.
 2. Write down your answer similar to the
earlier exercise in the same piece of
paper.

25. Exercise no. 2- measure the F1
again based on this information.

26. Is that all?
 No, you still need to remove the soil you
have excavated.
 So you need to write description again for
the removal of surplus soil.
 1st. Remove what?
 Answer: Surplus soil.
 2nd. To where?
 Answer: Away from site or off site(clause
D.19)
 3rd. Unit?
 M3 Clause D.19

27. Your answer
Removing surplus
excavated soil off site
including disposal to
contractor’s own tip.
Answer similar to excavation work for
foundation