Geology Assingment

TABLE OF CONTENTS

1.1- INTRODUCTION

1.2. SCOPE OF WORK

1.3- RELATIVE DENSITY AND CONSISTENCY

1.4- GROUND CONDITION AND SOIL PROPERTIES

1.5- GROUND WATER CONDITTON

1.6. CONCLUSION AND RECOMMENDATION

1.7- GENERAL

1.1-            INTRODUCTION

The Soil investigation provides the important information for the construction notably for the foundation. The Soil investigation will guide the methods of foundation construction (Shallow or deep foundation, with or without piles...)

On March 24, 2014, Research and Design Enterprise has been awarded a contract to undertake the soil investigation for FACTORY DEVELOPMENT FOR CONFIREL PRODUCTION LINE EXPANSION, located at Russian Confederation Boulevard, Chom Chao Commune, Dangkor District, Phnom Penh.

The works are following:

1. Soil boring tests for each 03 boreholes with SPT test every 1.50m intervals and 25.00 meters depths.

2. Laboratory testing of collected samples.

The field works have been carried out from March 24, 2014 and finished March 26, 2014. The laboratory testing and the report have been carried out from March 25, 2014 to March 31, 2014.

This report presents the ground conditions, soil mechanics, and results of Standard Penetration Test (SPT), and field boring logs recording.

1.2. SCOPE OF WORK

The scope of work for investigation included the following:

1.2.1- STANDARD PENETRATTON TEST (SPT)

Standard Penetration Test was carried out 1.50m intervals inside the each boring hole. A standard split spoons of 50.8mm diameter with a ball check value on the top and harden steel cutter. A Standard spilt spoon was installed and drives into the soil by a 63.5kg standard trip hammer falling freely from a fixed height of 760mm along a guide rod. The blow counts defined for each 150mm penetration of the seating drive. The total penetration of the spoon is 450mm and the numbers of blow N-value for last 300mm. Penetration was recorded as the N-value of the soil stratum encountered which indicated the relative density of non-cohesive soil as well the consistency of the cohesive soil.

1.2.2 - SAMPLING

- Undisturbed samples: Undisturbed samples were taken in the natural state of the soil from firm stiff clay and sandy clay. The undisturbed samples were taken by thin wall tube sampler in the natural state.

- Disturbed samples: The disturbed samples were taken at a rate of 1.5m and all strata in the each borehole. The disturbed samples were also collected in soft to stiff clay and sandy soil.

1.3. RELATIVE DENSITY AND CONSISTENCY

The relationship between Standard Penetration Test result and consistency clay, silt soil (Cohesive soil) and relative density for sandy soil (non-cohesive soil) are shown in the table No 1 and 2,

The relation between S.P.T result and Consistency

For Clay, Silt, Clayed-Silt and Silly-Clay (Cohesion Soils)

Table 1

S.P.T N Value (blows/ 300mm)	CONSISTENCY
0 to 2	very soft
2to 4	Soft
4 to 8	Medium Stiff
8 to 15	Stiff
15 to 30	Very Stiff
30 over	Hard

The Relation between S.P.T Result and Relative Density

For Sand and Gravel (Cohesion less Soil)

S.P.T N Value (blows/ 300mm)	RELATIVE DENSITY
Less than 4	Very loose
4 to 10	Loose
10 to 30	Medium dense
30 to 50	Dense
Over 50	Very dense

 Table 2

1.4. GROUND CONDITION AND SOIL PROPERTIES

For this site the ground condition from the ground surface to 25.00m depths consisted of filling process of Mekong River or Geology was in 4th Era (Young alluvium). The soil condition encountered on boreholes has been into strata as follows:

BOREHOLE No 1

Stratum No	Description of soil strata	N-value Blows /300mm
1	-Made ground, encountered from top to 2.50m depths
2	-Red stiff Lean Clay, encountered from 2.50m to 5.80m.	N-1 1 :N-10
3	- Yellow grey dense Clayey SAND, encountered from 5.80m to 8.30m.	N-36;N-46;N-50
4	Yellow very dense Clayey SAND, encountered from 8.30m to 13.20m.	Nr=54blows N-67;N-80;N-71
5	White grey very hard Fat CLAY with sand, encountered from 13.20m to 18,2m,	N-60
6	Yellow very dense Clayey SAND, encountered from 18.20m to 20.60m	N-60;N-76;N-61
7	Yellow very hard Lean CLAY, encountered trom20.60m to 25.00m.	Nr=52blows Nr=81blows

BOREHOLE No 2

Stratum No	Description of soil strata	N-value Blows /300mm
1	Made ground, encountered from top to 2.30m depths	N-19
2	Red very stiff Sandy Lean CLAY, encountered from 2.30m to 6.70m,	N-19
3	Grey medium dense Clayey SAND, encountered from 6.70m to 10.60m	N-27
4	Yellow grey very dense Clayey SAND, encountered from 10.60m to 14.80m.	N-61
5	Yellow grey dense Clayey SAND, encountered from 14.80m to 17.70m,	N-44
6	Grey very dense Clayey SAND, encountered from 17.70m to 21.20m.	N-66;N-69
7	Yellow grey very dense Clayey SAND, encountered from 21.20m to 25.00m,	N-105;N-121 ;N- 93;N-111

BOREHOLE No 3

Stratum No	Description of soil strata	N-value Blows /300mm
1	Made ground, encountered from top to 2.20m depths.
2	Yellow very stiff Sandy Lean CLAY, encountered from 2.20m to 6.20m.	N-24
3	-Yellow very dense Clayey SAND, encountered from 6.20m to 11.50m.	N-51
4	Yellow medium dense Clayey SAND, encountered from 11.50m to 15.20m	N-20
5	Yellow grey dense Clayey SAND, encountered from 15.20m to 18.60m.	N-49
6	Yellow very dense Clayey SAND, encountered from 18.60m to 22.40rn.	N-63
7	Yellow grey very dense Clayey SAND, encountered from 22.40m to 25.00m,	N-121 ;N-79; N-83;N-76; N-73;N-79; N-161 ;N-76

1.5. GROUND WATER CONDITION

The ground water level is important for soil investigation, because the variation of the ground water level, the characteristic of soil mechanic can be changed. During the boring activities, water is found at a greater depth (Water strike), but few hours after the boring completed, water table is stabilized a higher level (Ground water level as shown in table 3).

Table No 3

Borehole No	Boring started date	Boring finished date	Water strike (m.)	Water level (m.)	Date measured
BH.1	24/03/2014	24/0312A14	>25.00	>25.00	24/0312014
BH.2	25/0312014	25/03/2014	>25.00	>25.00	25/03/2014
BH.3	26/0312014	26/03t2014	>25.00	>25.00	2610312014

For this area the ground water table varies according to the season: increase in rainy season and decrease in dry season.

1.6- CONCLUSION AND RECOMMENDATION

Based on the soil data from 03 boring holes, the following recommendation can be presented:

a- For this Project, the Pile Foundation (Bored Pile Foundation) is necessary.

b- The allowable bearing capacity for Single Bored Pile foundation is presented in the Table No 4.

TABLE No 4

FOR BORED PILE

Safety factor SF=2.50

Borehole number	Pile size	Pile depth	Pile length	Friction load	End pile load	Allowable Pile Load
(No)	(m)	(m)	(m)	(kN)	(kN)	(kN)
BH-1	Ø 0.50	20	12	1149.42	589.05	1227.1*
	Ø 0.60	20	12	1379,30	848.23	1767.15*
	Ø 0.70	20	12	1609.18	1154.54	2405.28*
	Ø 0.80	20	12	1839.07	1507.96	3141.59*
	Ø 0.90	20	12	2068.95	1908.52	3976.08*
	Ø 1.00	20	12	2298.83	2356.19	4655.03
	Ø 1.20	20	12	2758.60	3365.90	6124.50
	Ø 1.50	20	12	3448.25	4716.32	8164.57
BH-2	Ø 0.50	20	12	1343,91	471.24	1227.18*
	Ø 0.60	20	12	1612.69	678.58	1767.15*
	Ø 0.70	20	12	1881.47	923.63	2405.28*
	Ø 0.80	20	12	2150.25	1206.37	3141.59*
	Ø 0.90	20	12	2419.03	1526,81	3945.85
	Ø 1.00	20	12	2687.82	1884.96	4572.77
	Ø 1.20	20	12	3225.38	2714.34	5939.71
	Ø 0.50	20	12	1281 .90	589,05	1227.18.
BH-3	Ø 0.60	20	12	1538.28	848.23	1767.15*
	Ø 0.70	20	12	1794.66	1154.54	2495,28.
	Ø 0.80	20	12	2051.04	1507,96	3141.59*
	Ø 0.90	20	12	2307.42	1891 .87	3976.08*
	Ø 1.00	20	12	2563.80	2218.95	4782.75
	Ø 1.20	20	12	3076,56	2943.22	6019.78
	Ø 1.50	20	12	3845.70	4204.92	8050.63

Note: -10kN=1 tone

- (*) is allowable bearing capacity for the concrete pile,

1.7. GENERAL

The analysis and recommendation submitted in this report are based on available information. Since significant variations in soil conditions may occur between the boring, it is recommended that pile experienced soil engineer to assure that the bearing capacity conform to the design and specifications.

The suggestion and recommendation herein are based on available data obtained from limited specified soil information, the homogeneity of soil formation assumption, and equations involved in the calculation, which are believed to be reliable. However, such prediction or recommendations should be verified by full-scale test of investigation during construction period to obtain more precise reliable data. Construction method must be adopted to best suit the analysis method assumption .We do not make any representations as to its accuracy or completeness .Any, data or design criterion is only current solutions which are subjected to change or revise.

This report has been prepared in order to aid in the evaluation of the site conditions only, to assist the engineer in the design of the project, based on our understanding of the design details, criteria & utilization of the project as outlined herein. If our understanding of the design and utilization is not correct, we should be promptly informed of the correct data so that we may revise our recommendations as appropriate.