1. Lecture 1 - Excavation
Objectives:-
1. To learn the various types of excavation works.
2. To relate the excavation works as per clauses in SMM2
3. To learn the methods of measurement as per clause D.10
– Depth classification
Outcomes:-
1. Able to differentiate the different types of excavation
bases on clauses D.12.
2. Able to determine the different units of measurement
based on the clauses in D10, D11 and D12.

2. Excavation

3. Excavation
Cut
Remove
Backfill

4. For a start we need to remove the top soil to
an average depth of 200mm
100.00
m
35.00m

5. Before you start to measure
check this out:-
 1. Which clause?
 Answer: Clause D.7 page 17
 2. Unit of measurement ?
 Answer: m2 Clause D.7
 3. Others?
 Answer: To state average depth.

6. Suppose we need to do an excavation to a
footing (F1) we need to know what?
Answer : Length. Width and
Depth

7. So what is the depth?

8. So we have two excavation depths:
a.The first is the oversite excavation depth
which is 200mm from ground level.
b.The second is the footing excavation depth
which is 2.75m from reduced level.

9. How do we know the
excavation depth to footing?
 1st. The civil engineer will provide the information in two
ways:
 A. The depth from ground level or from reduced levels.
 B. Based on the TBM ( Temporary Bench mark).

10. Ground Levels
Engineers may just give you the depth
2.95m from ground level.

11. In most cases Engineer will
give the ground level and
footing levels

12. How is excavation actually carried
out?
A B
900m
m
900mm
F1
Excavate footing
F1.
Size 900 x 900x
1650mm

13. What is the volume of
Excavation?a. A
b. A + B + C

14. Depth of Excavation
Footing A
Footing B

15. We need to prevent the soil from falling
due to the nature of the soil
Planking
and
Strutting

16. SOMETIMES THE SOIL IS JUST TOO WEAK
,SO WE NEED TO PROVIDE SHEET PILING
TO THE SIDES OF THE FOUNDATION.
SHEET
PILING

17. Depth classification (Clause
D.10 page 17)
0.25m
1.00m
2.00m 4.00m

18. Reasons for the depth classification
 1. Different depth will
result in increased
difficulty in
excavation.
 Increased depth will
pose danger to
workers so temporary
support could be
used.
 It will result in using
more complicated
machinery.
 It enables contractors
to price accordingly

19. Levels
Sea level:-
0.00m
5.00m
The top of this hill is 5.00m
above sea level.

20. Clause D12.2 Excavation in rock
Normal soil
Rock
Bulldozer with ripper

21. How to get rid of rocks?
Excavator
Jack hammer
Chemical
Dynamite

22. How to measure rock?
1. To measure rock
separately from
normal earth.
2. To measure rock
as an extra over
item:-
A. Total excavation
ie. A+B.
B To include rock ie
B as a new item as
extra over.
A
B

23. Exercise :- Find out the
excavation work to area A and B
100.00m
80.00m
25.00m
18.00m
Level:- 6.50m
Level:- 7.50m
A
B
Plan view
Platform level:- 3.50m