2011-12- Spring Term
Instructors: Assoc.Prof. Aykut ŞENOL
Res. Assist. Z. Nil TAYLAN KUTLU
HOMEWORK # 1 (Site Investigation and In-Situ Tests)
1.
What is “Site Investigation”? What is the purpose of site investigation? Explain the steps of a site investigation program. (15 pts.)
2.
Briefly explain testing procedures of the Standard Penetration Test. Why is this test performed? What are the factors that affect the measured N values in a Standard
Penetration Test? Try to give reasons for each factor and explain how they change the test results. (15 pts.)
3.
Which correction factors are used in the Standard Penetration Test? (10 pts.)
4.
Explain the procedures for Cone Penetration Test (CPT) and name the measured parameters and the correlations associated with the test results (10pts.).
5.
A Standard penetration test is performed in field by using a safe type hammer and standard sampler. The diameter of the borehole is 80 mm. The SPT results are given in the table below. The GWT is at a depth of 9 m. Assume an average unit weight for the soil,  n

18.C kN/m
3 and  sat

20.D kN/m
3 above and below the GWT respectively.
The Energy Ratio of the system is equal to E.R%=60 for the used safe type hammer. a.
Determine the field SPT number (N field
or N
30
) for each test data point. (5 pts.) b.
Using the proper correction factors, calculate the corrected SPT number, (N
1 for each test data point. (20 pts.)
)
60 c.
Using the correlations between SPT-N and soil parameters, give information about the consistency or packing status of the soil layers. Determine the strength parameters of the soil layers using these correlations. (25 pts.)
Depth
(m)
0-15 cm
SPT
15-30 cm
30-45 cm
Soil type
1.50
3.00
4.50
6.00
7.50
9.00
10.50
12.00
13.50
15.00
4
3
4
4
2
3
7
9
1D
1A
2
5
5
4
5
6
1A
1B
1C
10+E
4
4
3
6
4
7
9
1C
1D
10+F
Sand
Sand
Sand
Sand
Sand
Sand
Silty fine sand
Silty fine sand
Silty fine sand
Silty fine sand
Notes:
Assume that your student ID is 010040358. You will take A, B, C and D as follows:
0 1 0 0 4 0 3 5 8
A B C D
A=4
B=3
C=5
D=8
E=B+D=11
F=C+D=13
Remember to cite your references, especially when using the correlations.
The deadline for the assignment submission:
12.03.2012