Prject Foundation

NO. CONTENT PAGE

1.0 INTODUCTION1.1 Site Location1.2 Method of investigation

2

2.0 DESIGN OF FOUNDATION2.1 Borehole Log Data 2.2 Soil Layer Strata2.3Designing

3

3.0 JUSTIFICATION3.1 Summary Of Result

7

4.0 DOCUMENTATION4.1 Double Storey Plan

8

5.0 CONCLUSION 9

6.0 REFERENCE 10

7.0 APPENDIX 11

1

1.0 INTRODUCTION

1.1 Site Location

Soft clay is one of the problematic soils which are commonly found along the coastal areas at west peninsular Malaysia. Consolidation settlement normally will take a long period of time and it may cause problems to the construction structure if it is built before the settlement is completed. The main objectives of this project are to design of foundation using pile at clay soil. The location for this project at Universiti Tun Hussien Onn Malaysia, Johor. Borehole log data sheet have been used from standard penetration test (SPT).

1.2 Method Of Investigation

The purpose of the Standard Penetration Test (SPT) is to identify the soil stratification and engineering properties of the soil layer. During the SPT, it was possible to take undisturbed samples (using split barrel-sampler) which were used to further laboratory tests.

The in situ penetration test provides a soil sample for identification purposes and for the laboratory tests that allow the use of disturbed samples.

The method of sampling soil consists of driving a split-barrel sampler to obtain a representive, disturbed sample and to simultaneously obtain a measure of the resistance of the subsoil to the penetration of a standard sampler. The resistance to penetration is obtained by counting the number of blows required to drive a steel tube of specified dimensions into the subsoil to a specified distance using a hammer of a specified weight (mass).

All pertinent borehole data, penetration resistance, and sample data must be recorded on a boring log data sheet. The depths at the top or bottom of each 150mm increment of sampler penetration along with the number of blows required to affect that segment of penetration should be reported. Data obtained from SPT,N-value is collected from preliminary test and real test.

The SPT aims to determine the SPT value, which gives an indication of the soil stiffness and can be empirically related to many engineering properties. After the test, the sample remaining inside the split spoon is preserved in an airtight container for inspection and description.

2

2.0 DESIGN OF FOUNDATION

2.1 Borehole Log Data

Depth (m) N Value Soil / rock descripitions

0-1 0 Very Soft Clay

1-2 0 Very Soft Clay

2-3 0 Very Soft Clay

3-4.5 0 Very Soft Clay

4.5-5 2 Soft Clay

5-6 3 Soft Clay

6-7 3 Ditto

7-8 3 Soft Clay

8-9 2 Soft Clay

9-10 2 Ditto

10-11 2 Soft Clay

11-12 2 Soft Clay

12-13 2 Ditto

13-14 2 Ditto

14-15 3 Clay

15-16 3 Clay

16-17 3 Ditto 

17-18 6 Clay

18-19 6 Ditto

19-20 9 Stiff Clay

20-30.385 50 Very Dense

3

2.2 Soil Layer Strata

GROUND LEVEL

0.6mVery Soft Clay ,

Very Soft Clay ,

4.5m

12m Soft Clay ,

Clay ,

20m

30.4m Very Hard/Bedrock ,

4

2.3 Designing

Estimating Pile Capacity for QP

Cu = 150 kN/

(P16)

Area = 2.95 x 2.95 = 8.7

Irr/Ir =

(Vesic Equation)

5

Estimating Pile Capacity for Qs

(kN/ )

0.6 7.5

4.5 18.0

60.7

12.0

20.0 130.2

246.6

30.4

Depth(m)

P= 4x 2.95 = 11.8m

6

L = 30.4m

( Method)

Q allowable

3.0 JUSTIFICATION

3.1 Summary Of Result

This project have been done at Universiti Tun Hussien Onn Malaysia area. Based on SPT

value obtained, we found that bedrock level was at 30.4m from ground level. Briefly, the average

soil that has been found is clay which at the 0-4.5m,the soil identified as very soft clay having

7

While at level 4.5-12m,the soil identified as soft clay having

.For level at 12-20m,clay soil are identified having Bedrock layer are

found at 30.4m from ground level which having The water table level

obtained at 0.6m from ground surface level.

Based on building load calculation which obtained from esteem software, having that

maximum load from building is 873.9kN at point 16.The cross section of this foundation is

2.95mx2.95m at 30.4m height.

Based on estimating pile capacity of Qp calculation, Vesic equation has been used to

calculated resulting 15020.6kN.Whilst estimating pile capacity of Qs calculation using method

resulting 11445.7kN.The value of allowable load is 6616.6kN are obtained.

Refer to the building plan layout, at the beginning of designing we are chosen pad footing.

As a result, we found that footing was not efficiency to bearing building load. Then pile

foundation designing are useable for this project which suitable for that clay soil. In that case, it

may lowering the settlement and can reduce foundation construction cost efficiency.

8

4.0 DOCUMENTATION4.1 Double Storey

Plan

9

5.0 CONCLUSION

The double storey house was located at Universiti Tun Hussien Onn Malaysia area. Site

investigation method that have been used is Standard Penetration Test (SPT). This test was

resulted borehole log data sheet at the end. Based on SPT value obtained, bedrock level was

located at 30.4m from surface ground level. The average soil condition in this location is clay.

Based on calculation obtained from esteem software and manual calculation, maximum

load from building is 873.9kN at point 16 while the Qp value is 15020.6kN using vesic equation.

Then the values for Qs are obtained 11445.75kN using method. Factor of safety that have been

used is 4 and resulting allowable load is 6616.6kN.The cross section of this foundation is

2.95x2.95m.

Briefly, load allowable are more that ultimate load. It’s indicated that these piles are

suitable to bearing load above it. Piling usage is suitable for soil layer in highly compressible and

too weak to support the load whilst expansive and collapsible soil may be present at the site of a

proposed structure. Furthermore, to avoid the loss of bearing capacity that a shallow foundation

might suffer because of soil erosion at ground surface.

10

6.0 REFERENCE

1. BrajaM.Das( ,Prinsiples Of Foundation Engineering

2. Tomlinson.M ,woodwatd.J,Pile Design And Construction Practice

3. Rajapakse.R,Pile Design And Construction Rules Of Thumb

4. Farhan.M,A Study Of Consolidation ,Shear Strength And Bearing Capacity Of Soft Clay

Improved By Vertical Drain

5. SulaimanNasran,Kajian Parameter Kekuatan Ricih Tanah Liat Lembut Menggunakan

Penstabil Slag-Simen

6. NoorainSiti,The Performance Of Trial Embankment On Soft Soil At RECESS UTHM,

Malaysia

11

7.0 APPENDIX

12

13