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TOPIC 1 INTRODUCTION TO SOIL MECHANIC

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1 TOPIC 1 INTRODUCTION TO SOIL MECHANIC
Course : S0705 – Soil Mechanic Year : 2008 TOPIC 1 INTRODUCTION TO SOIL MECHANIC

2 CONTENT INTRODUCTION (SESSION 1 : F2F)
SOIL CHARACTERICTIC (SESSION 1 : F2F) SOIL CLASSIFICATION (SESSION 2 : F2F) SOIL COMPACTION (SESSION 3-4 : F2F) SOIL INVESTIGATIONS (SESSION 5-6 : OFC) Bina Nusantara

3 SESSION 1 INTRODUCTION SOIL CHARATERICTIC
Bina Nusantara

4 DEFINITION OF SOIL Soil is a natural body comprised of solids (minerals and organic matter), liquid, and gases that occurs on the land surface, occupies space, and is characterized by one or both of the following: horizons, or layers, that are distinguishable from the initial material as a result of additions, losses, transfers, and transformations of energy and matter or the ability to support rooted plants in a natural environment. Soil is formed over a long period of time. The formation of soil happens over a very long period of time. It can take 1000 years or more. Soil is formed from the weathering of rocks and minerals. The surface rocks break down into smaller pieces through a process of weathering and is then mixed with moss and organic matter. Bina Nusantara

5 SOIL MECHANIC/GEOTECHNICAL ENGINEERING
Geotechnical engineering is the branch of civil engineering concerned with the engineering behavior of earth materials. Geotechnical engineering includes investigating existing subsurface conditions and materials; assessing risks posed by site conditions; designing earthworks and structure foundations; and monitoring site conditions, earthwork and foundation construction. A typical geotechnical engineering project begins with a site investigation of soil, rock, fault distribution and bedrock properties on and below an area of interest to determine their engineering properties including how they will interact with, on or in a proposed construction. Site investigations are needed to gain an understanding of the area in or on which the engineering will take place. Investigations can include the assessment of the risk to humans, property and the environment from natural hazards such as earthquakes, landslides, sinkholes, soil liquefaction, debris flows and rock falls. Bina Nusantara

6 SOIL FORMATION Weathering is the process of the breaking down rocks. There are two different types of weathering. Physical weathering and chemical weathering. In physical weathering it breaks down the rocks, but what it's made of stays the same. In chemical weathering it still breaks down the rocks, but it may change what it's made of. For instance, a hard material may change to a soft material after chemical weathering. STAGE STAGE STAGE 3 Bina Nusantara STAGE 4

7 SOIL PROFILE Bina Nusantara

8 SOIL PROFILE Bina Nusantara

9 SOIL TYPES SOIL TYPES RESIDUAL SOIL SEDIMENT SOIL ALLUVIUM SOIL
LACUSTRINE SOIL MARINE SOIL PARTICULAR SOIL EXPANSIVE SOIL ORGANIC SOIL COLLAPSIBLE SOIL QUICK CLAY Bina Nusantara

10 BASIC CHARACTERISTIC PARTICLE BONDING
THE PARTICLE BONDING IS VERY WEAK SO RELATIVELY EASY TO GOING TO CHANGE AND HAVE NON-LINEAR BEHAVIOUR AND CHARACTERISTIC SHAPE, SIZE AND STRUCTURE OF SOIL PARTICLE Cohesive Soil Non-cohesive Soil Bina Nusantara

11 Bina Nusantara

12 LOOSE SAND DENSE SAND Bina Nusantara

13 PHYSICAL PROPERTIES OF SOIL
BASIC DEFINITION AND PHASE RELATIONS Air Water Soil Mass Bina Nusantara

14 VOID RATIO (Angka Pori) ; e : The ratio of void volume (Vv) to soil volume (Vs)
POROSITY (Porositas) ; n : The ratio of void volume (Vv) to total volume (V) 0  n  1 RELATIONSHIP BETWEEN VOID RATIO AND POROSITY or Bina Nusantara

15 WATER CONTENT (kadar air) ;  : The ratio of the amount of water (Ww) in the soil (Ws) and expressed as a percentage 0% <  <  DERAJAT KEJENUHAN (DEGREE OF SATURATION) ; S : The ratio of water volume air (Vw) to void volume (Vv) and expressed as a percentage 0%  S  100% Bina Nusantara

16 UNIT WEIGHT (Berat Volume) : The ratio of weight to volume
SPECIFIC GRAVITY (Berat Jenis) ; GS : The ratio of unit weight of soil to unit weight of water RELATIVE DENSITY (Kepadatan Relatif) ; Dr : Bina Nusantara

17 RELATIONSHIP OF SOIL PARAMETERS
Bina Nusantara

18 SESSION 2 SOIL CLASSIFICATION
Bina Nusantara

19 TYPE OF CLASSIFICATION:
SOIL CLASSIFICATION PURPOSE: To classified the soil into a group according to the soil behaviour and physical shape TYPE OF CLASSIFICATION: CLASSIFICATION BY VISUAL AASHTO UCS SOIL TESTS ATTERBERG LIMIT SIEVE ANALYSIS HYDROMETER ANALYSIS Bina Nusantara

20 Atterberg Limit Cohesive Soil Base on water content
Consistency Limit : Liquid Limit, Plastic Limit and Shrinkage Limit SL PL LL Water content Volume Solid Plastic Liquid Plasticity Index PI Semi Solid Bina Nusantara

21 Two main methods to determine the liquid limit :
LIQUID LIMIT (LL) The liquid limit is that moisture content at which a soil changes from the liquid state to the plastic state. It along with the plastic limit provides a means of soil classification as well as being useful in determining other soil properties Two main methods to determine the liquid limit : Cone Pentrometer Method Casagrande Method Bina Nusantara

22 CONE PENETROMETER METHOD
Bina Nusantara

23 CONE PENETROMETER METHOD
SAMPLE PREPARATION : Any coarse particles present need to be removed, by hand or by wet sieving (coarse particles are defined as any particles retained on a 425 micron sieve). Next a representative sample is required weighing around 200g. This sample should be cut into small pieces using a knife or shredder and any coarse particles removed with tweezers. Then the sample is transferred to a flat glass plate, distilled water is added and the soil and water are mixed thoroughly with two palette knives until the mass becomes a thick homogenous paste. The paste is then transferred to an air tight container for 24 hrs to allow the water time to penetrate the soil fully. Bina Nusantara

24 CONE PENETROMETER METHOD
TESTING PROCEDURES: Push a portion of the sample into the cup with a palette knife taking care not to trap air, strike off the excess and with the straight edge to get a smooth and level surface. With the penetration cone raised and locked lower the supporting assembly so that the tip of the cone just touches the surface of the soil in the cup. When the cone is in position a slight movement of the cup will mark the surface. Lower the stem of the dial gauge so that it comes into contact with the cone shaft and gives a reading, record the reading to the nearest 0.1mm. Release the cone for a period of 5s (plus or minus 1s) if the apparatus is not fitted with an automatic release and locking device take care not to jar the apparatus during the procedure. After 5s the cone should have, to some extent, penetrated the smooth surface of the soil, lock the cone in this new, lower, position and lower the stem of the dial gauge again so that it just comes into contact with the cone shaft, record this new reading to the nearest 0.1mm Lift out the cone and clean it carefully, to avoid scratching, then add a little more wet soil and repeat the test. Bina Nusantara

25 CONE PENETROMETER METHOD
Notes: If the difference between the first and second penetration readings is less than 0.5mm record the average of the two penetrations. If the second penetration is more than 0.5mm and less than 1mm from the first, carry out a third test. If the overall range is then not more than 1mm record the average of the three penetrations. If the overall range is more than 1mm remove the soil from the cup, remix and repeat until consistent results are obtained. Bina Nusantara

26 CONE PENETROMETER METHOD
TESTING PROCEDURES (continued): Take a moisture content sample of about 10g from the cup around the area penetrated by the cone. Repeat the test at least three more times using the same sample of soil - to which further increments of distilled water have been added. Proceeding from the drier state to the wetter. The amount of water added shall be such that a range of penetration values of approximately 15-25mm is covered by four or more test runs and is evenly distributed. Each time the soil is removed from the cup for the addition of water the cup and cone must be thoroughly cleaned, if the soil is to be left for any length of time it should be covered with a damp cloth to prevent it drying out. Bina Nusantara

27 CONE PENETROMETER METHOD
Result Calculate the moisture content of each test sample, plot the relationship between the moisture content and the corresponding cone penetration recorded on a linear chart, with the percentage moisture content as ordinates on the linear scale and the number of bumps on the opposite scale, draw a line of best fit between the points. From the curve read off the moisture content corresponding to a cone penetration of 20mm to the first decimal place, express this moisture content to the nearest whole number and report it as the liquid limit. Bina Nusantara

28 CONE PENETROMETER METHOD
Example of Typical Result Bina Nusantara

29 CASAGRANDE METHOD Per definition as water content at 25 blows
METHOD A : MULTI-POINT Bina Nusantara

30 CASAGRANDE METHOD METHOD B : SINGLE-POINT Bina Nusantara

31 CASAGRANDE METHOD Bina Nusantara

32 CASAGRANDE METHOD Bina Nusantara

33 PLASTIC LIMIT (PL) Plastic behaviour
The test is done by rolling up the soil sample to 3.2mm diameter Defined as the water content, in percent, at which the soil crumbles, when rolled into threads of 1/8 in (3.2mm) in diameter. Bina Nusantara

34 WS <<<  easy to have volume change
SHRINKAGE LIMIT (SL) Test Standard : ASTM D 427 Defined as the moisture content, in percent, at which the volume of soil mass ceases to change WS <<<  easy to have volume change Bina Nusantara

35 CONSISTENCY RELATIONSHIP
Plasticity Index (PI) PI = LL - PL Liquidity Index (LI) Consistency Index (CI) Bina Nusantara

36 CONSISTENCY RELATIONSHIP
Activity (A) A <  non-active clay 0.75 A<1.25  normal clay A   active clay Bina Nusantara

37 Bina Nusantara

38 The testing should be only carried out once for one sample
Sieve Analysis Test Standard ASTM D422, AASHTO T88 The testing should be only carried out once for one sample Bina Nusantara

39 Curve of Particle Size Distribution
Bina Nusantara

40 Principle of work : sedimentation of soil particle in water
Hydrometer Analysis Used to extend the distribution curve of particle shape and to predict the particle size less than 200 sieve Principle of work : sedimentation of soil particle in water Assumption : All particle have rounded shape Stoke rule is valid : Bina Nusantara

41 BASIC OF CLASSIFICATION
Bina Nusantara

42 CLASSIFICATION BY VISUAL
Carried out by direct observation (visual examination) to the sample and approximate the type of soil by: Colour Smell Sense/Feeling endurance Swelling Sedimentation Bina Nusantara

43 The soil classified into 7 major categories (A-1 to A-7) Based on:
AASHTO The soil classified into 7 major categories (A-1 to A-7) Based on: The result of Sieve Analysis Atterberg Limits The soil quality based on Group Index Calculation Plasticity Index for sub group A-7-5  LL minus 30. Plasticity Index for sub group A-7-6 > LL minus 30 Bina Nusantara

44 F = The percentage of soil pass sieve no. 200
AASHTO GROUP INDEX F = The percentage of soil pass sieve no. 200 Subgrade Group Index Value Very good Soil Class A-1-a (0) Good 0 – 1 Medium 2 – 4 Bad 5 – 9 Very Bad Bina Nusantara

45 AASHTO GROUP INDEX Rules: If GI < 0, GI = 0 GI  Integer Number
No upper limit of GI For coarse grained, GI = 0 for A-1-a, A-1-b, A-2-4, A-2-5 and A-3 GI =0,01(F-15)(PI-10) for A-2-6 and A-2-7 Bina Nusantara

46 AASHTO Bina Nusantara

47 AASHTO PROCEDURE Bina Nusantara

48 AASHTO Bina Nusantara

49 USCS (UNIFIED SOIL CLASSIFICATION SYSTEM)
Soil classification determined base on the soil parameter i.e.: Diameter of soil particle Gravel : pass sieve no.3 but retained at sieve no. 4 Sand : pass sieve no. 4 but retained at sieve no. 200 Silt and Clay : pass sieve no. 200 Coefficient of soil uniform Atterberg Limits Bina Nusantara

50 USCS (UNIFIED SOIL CLASSIFICATION SYSTEM)
Soil Type Prefix Sub-group Suffix Well Graded W Gravel G Poor Graded P Sand S Silty M Clayey C Silt M Clay C LL < 50% L Organic O LL > 50% H Peat Pt Notation G = Gravel M = Inorganic Silt C = inorganic Clay O = Organic Silt or Clay W = Well Graded P = Poorly Graded L = Low Plasticity H = High Plasticity Bina Nusantara

51 USCS (UNIFIED SOIL CLASSIFICATION SYSTEM)
Steps of determination Determine the soil particle by count the percentage of soil pass sieve no If the percentage less than 50% so the soil is classified as coarse grained. Determine the percentage of soil pass sieve no. 4 and retained at sieve no If the percentage less than a half of the percentage of coarse material, the soil is classified as gravelly soil Bina Nusantara

52 THE FLOW CHART OF USCS METHOD
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53 FLOWCHART OF USCS METHOD (CONTINUED)
Bina Nusantara

54 FLOWCHART USCS METHOD (CONTINUED)
Bina Nusantara

55 USCS (UNIFIED SOIL CLASSIFICATION SYSTEM)
Bina Nusantara

56 USCS (UNIFIED SOIL CLASSIFICATION SYSTEM)
Bina Nusantara

57 COMPARISON OF AASHTO AND USCS
Bina Nusantara

58 EXAMPLE RESULT OF ANALYSIS AND ATTERBERG LIMIT
GROSS WEIGHT OF SAMPLE = 1000 GRAM Sieve Size Soil 1 Soil 2 Soil 3 No. 4 990 gram 970 gram 1000 gram No. 10 920 gram 900 gram No. 40 860 gram 400 gram No. 100 780 gram 80 gram No. 200 600 gram 50 gram LL 20 - 124 PL 15 47 PI 5 NP 77 Bina Nusantara

59 Sieve Size Soil 1 Soil 2 Soil 3 No. 4 99 % 97 % 100 % No. 10 92 % 90 %
86 % 40 % No. 100 78 % 8 % No. 200 60 % 5 % LL 20 - 124 PL 15 47 PI 5 NP 77 Bina Nusantara

60 SESSION 3-4 SOIL COMPACTION
Bina Nusantara

61 INTRODUCTION Soil compaction is defined as the method of mechanically increasing the density of soil.  In construction, this is a significant part of the building process.  If performed improperly, settlement of the soil could occur and result in unnecessary maintenance costs or structure failure Bina Nusantara

62 SOIL COMPACTION PURPOSE Improving the soil quality by:
Increasing the shear strength of soil Improving the bearing capacity of soil Reduces the settling of soil Reduces the soil permeability To control the relative volume change Bina Nusantara

63 4 types of compaction effort on soil :
Vibration Impact Kneading Pressure Bina Nusantara

64 SOIL COMPACTION BASIC THEORY
Developed by R.R. Proctor at 1920-an with 4 variables : Compaction efforts (Compaction Energy) Soil types Water content Dry Unit Weight LABORATORY COMPACTION TEST Standard Proctor Test Modification Proctor Test Dietert Compaction Harvard Miniatur Compaction Bina Nusantara

65 STANDARD PROCTOR TEST The soil is compacted at cylindrical tube
Specification of test and equipments Hammer weight = 2,5 kg (5,5 lb) Falling height = 1 ft Amount of layers = 3 No. of blows/layer = 25 Compaction effort = 595 kJ/m3 Soil type = pass sieve no. 4 The test is carried out several time with different water content After compacted, the weight, moisture content and unit weight of samples are measured Test Standard : AASHTO T 99 ASTM D698 Bina Nusantara

66 MODIFIED PROCTOR TEST The soil is compacted at cylindrical tube
Specification of test and equipments Hammer weight = 4.5 kg (10 lb) Falling height = 1.5 ft Amount of layers = 5 No. of blows/layer = 25, 56 Compaction effort = 2693 kJ/m3 Soil type = pass sieve no. 4 The test is carried out several time with different water content After compacted, the weight, moisture content and unit weight of samples are measured Test Standard : AASHTO T 180 ASTM D1557 Bina Nusantara

67 TEST RESULT Bina Nusantara

68 DIETERT COMPACTION Principle of work:
Impact Compaction is acted like Proctor Test The size of soil particle: Pass sieve 2 mm The falling height is more constant  reproducible To get the approximation of compaction characteristic of less soil sample Purpose for other soil testing such as unconfined compression test Bina Nusantara

69 HARVARD MINIATUR COMPACTION
Principle of work : Alat pemadat sheepsfoot roller  aksi kneading pada tanah Spring Load Tamper : Spring 40 lb The size of soil particle: Lolos saringan 2 mm Pemadatan dalam 3 lapis dengan 25 tekanan per lapis  Standar Proctor Test Bina Nusantara

70 FIELD COMPACTION Type of Compaction Equipment : Smooth Wheel Roller :
compaction equipment which supplies 100% coverage under the wheel, with ground contact pressures up to 400 kPa and may be used on all soil types except rocky soils. Mostly use for proofrolling subgrades and compacting asphalt pavements. Bina Nusantara

71 FIELD COMPACTION Type of Compaction Equipment : Rubber Tire Roller :
A heavily loaded wagon with several rows of three to six closely spaced tires with tire pressure may be up to about 700 kPa and has about 80% coverage (80% of the total area is covered by tires). This equipment may be used for both granular and cohesive highway fills. Bina Nusantara

72 FIELD COMPACTION Type of Compaction Equipment : Sheepsfoot Roller :
This roller has many round or rectangular shaped protrusions or “feet” attached to a steel drum. The area of these protusions ranges from 30 to 80 cm2. Area coverage is about 8 – 12% with very high contact pressures ranging from 1400 to 7000 kPa depending on the drum size and whether the drum is filled with water. The sheepsfoot roller is best suited for cohesive soils. Bina Nusantara

73 FIELD COMPACTION Type of Compaction Equipment : Tamping Foot Roller :
This roller similarly to sheepsfoot roller, which has approximately 40% coverage and generate high contact pressures from 1400 to 8400 kPa. Tamping foot rollers are best for compacting fine-grained soils. Bina Nusantara

74 FIELD COMPACTION Type of Compaction Equipment : Grid Roller :
This roller has about 50% coverage and pressures from 1400 to 6200 kPa, ideally suited for compacting rocky soils, gravels and sand. With high towing speed, the material is vibrated, crushed, and impacted. Bina Nusantara

75 FIELD COMPACTION Type of Compaction Equipment : Baby Roller :
Small type of smooth wheel roller yang, which has pressure ranges from 10 to 30 kPa. The performance base on static weight and vibration effect. Bina Nusantara

76 FIELD COMPACTION Type of Compaction Equipment: Vibrating Plate :
Compaction equipment, which has plate shape. In Indonesia this equipment sometimes called as “stamper”. Usually used for narrow area and high risk when use large compaction equipment like smooth wheel roller etc. Bina Nusantara

77 FIELD COMPACTION Bina Nusantara

78 FIELD COMPACTION Bina Nusantara

79 FIELD COMPACTION Bina Nusantara

80 FIELD COMPACTION Bina Nusantara

81 CHARACTERISTIC AND APPLICATION
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82 CONDITIONER FACTORS Characteristic of compaction equipment
Weight and size Operation frequency and frequency range Soil Characteristic Initial density Soil type Size and shape of soil particle Moisture Content Compaction Procedure No. of passes of the roller Layer thickness Frequency of operation of vibrator Towing speed Bina Nusantara

83 FIELD COMPACTION CONTROL
Excavate a hole with certain diameter and depth. Determine the mass of excavated material. Determine the moisture content Measure the volume of excavated material by: Ottawa Sand  Sand cone The balloon method Pouring water or oil Compute the total density,  and d,field Compare d, field with d,max and calculate the relative compaction Bina Nusantara

84 SPECIFICATION OF COMPACTION
End Product Specification Method of Specification Minimum soil sample 100 kg Need special experience to find out the optimum moisture content in order to get optimum compaction performance Bina Nusantara

85 RELATIONSHIP BETWEEN DENSITY AND CBR
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86 RELATIONSHIP BETWEEN DENSITY AND CBR
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87 Session 5 – 6 SOIL INVESTIGATION
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88 SOIL INVESTIGATION AND LABORATORY TESTS
LABORATORY TESTINGS EMPIRICAL CORRELATIONS CPT AND N-SPT VALUE BETWEEN SOIL PARAMETER Bina Nusantara

89 SOIL INVESTIGATION PURPOSE
To describe the soil condition and its stratification. To get the soil sample for laboratory testing undisturbed sample disturbed sample To find out the ground water level To get the soil properties directly In-situ Test Bina Nusantara

90 SOIL INVESTIGATION STAGES Site Inspection Initial Investigation
Cone Penetration Test (Sondir) Advance Investigation (detail) Boring and sampling Standard Penetration Test Pressuremeter Dilatometer Additional Investigation Bina Nusantara

91 SOIL INVESTIGATION DEPTH OF SOIL INVESTIGATION
Shallow Foundation : 3 x Foundation width (min. 9m) Raft Foundation : 2 x Foundation width Pile Foundation : 2 x Pile width (measured from pile tip) Pile + Raft Foundation : 2 x building width Retaining Earth Structure : 0.7 x cutting width or 1 x cutting height (take the biggest) Soil Embankment : 2 x embankment width Bina Nusantara

92 Bina Nusantara

93 SOIL INVESTIGATION NO. OF SOIL INVESTIGATION Initial Investigation :
Normal Soil : every 100 to 200 m Soft Soil : every 50 to 100 m Detail Investigation : Square structure : every 15 to 25 m Strip structure : every 25 to 50 m At the important side of the structure, the number of soil investigation can be increased Bina Nusantara

94 BORING INVESTIGATION AUGER BORING WASH BORING CORE DRILLING TEST PIT
Bina Nusantara

95 BORING INVESTIGATION AUGER BORING (PENGEBORAN MANUAL)
Carried out by pushing and rotating the auger into soil Limited application, only suitable for shallow foundation Not suitable for boring under ground water table Simple, easy to operate and minimum disturbance to soil Bina Nusantara

96 BORING INVESTIGATION WASH BORING (PENGEBORAN BILAS )
Use rotary bore machine Soil dig and washed by water circulation Can not used for soil identification Less suitable for rock boring Suitable for all type of soil Very suitable for soft soil Disturbance to soil structure is minimum Bina Nusantara

97 BORING INVESTIGATION CORE DRILLING (PENGEBORAN INTI)
Use rotary bore machine Single tube without water circulation Double or triple tube with water circulation Can use for rock Can identify soil directly Not suitable for boring of soft soil Can make a disturbance soil structure Bina Nusantara

98 BORING INVESTIGATION TEST PIT Carried by excavated soil manually
For shallow depth Difficult to apply to soil with high water level Very simple and relative cheap Identification can be done directly by visual. Large number of soil sample Bina Nusantara

99 UNDISTURBED SOIL SAMPLING (CONTOH TANAH TAK TERGANGGU)
SAMPLING METHOD UNDISTURBED SOIL SAMPLING (CONTOH TANAH TAK TERGANGGU) Sampling Technique Sensitive and soft to very soft clay or silt  thin wall tube + piston Soft to medium stiff clay or silt  shelby thin wall tube sampler Hard to very hard clay or silt  thick wall tube sampler or Denison or Pitcher samplers Bina Nusantara

100 THIN WALL and PISTON SAMPLER
Bina Nusantara

101 THICK WALL and DENISON SAMPLER
Bina Nusantara

102 SOIL SAMPLER TUBE (ASTM D1587)
Bina Nusantara

103 SAMPLING METHOD UNDISTURBED SOIL SAMPLE (CONTOH TANAH TAK TERGANGGU )
Storage Technique/Sample treatment The tube shall be covered by paraffin candle Storage at cool place and at vertical position Shall be labeled to facilitate soil identification The tube shall be folded by foam during transportation The laboratory tests shall be carried out as soon as possible Bina Nusantara

104 SAMPLING METHOD DISTURBED SOIL SAMPLE (CONTOH TANAH TERGANGGU )
Sampling Technique and Sample Treatment Can get from core drilling or SPT tube Shall be folded by plastic and storage at cool place Shall be labeled to facilitate soil identification Usually use for fill material Bina Nusantara

105 INSITU TEST (UJI LAPANGAN)
BASIC AND SIMPLE INSITU TEST Standard Penetration Test (SPT) Cone Penetration Test (CPT) INSITU TEST for DIRECT MECHANICAL PROPERTIES OF SOIL Field vane shear test  Soil Strength Pressuremeter Test/Lateral Load Test (LLT)  Soil Deformation Flat Dilatometer Test  Soil Deformation Plate Bearing Test  Strength and Deformation of Soil Bina Nusantara

106 STANDARD PENETRATION TEST (SPT)
PRINCIPLE OF WORK Carried out by punching the standard tube to bore hole using free fall 63.5 kg hammer from 760mm height. The number of blows required for spoon penetration of three 150mm. The number of blow counted at the last of 300mm penetration. RULES Dimension of SPT tube according to ASTM D1586 The hammer type is conventional or automatic Bina Nusantara

107 STANDARD PENETRATION TEST (SPT)
ADVANTAGES Could be used to identify soil types visually Could be used to get qualitative soil properties by empirical correlation LIMITATION The soil strength profile can not be measured continuously The high accuracy is needed during investigation in case of weight and falling height of hammer Bina Nusantara

108 SPT HAMMER Bina Nusantara

109 DIMENSION OF SPT TUBE Bina Nusantara

110 EXAMPLE OF BORING LOG AND SPT
Bina Nusantara

111 SPT EXECUTION Bina Nusantara

112 CONE PENETRATION TEST (CPT)
TYPE OF PENETROMETER AND PRINCIPLE OF WORK Mechanical friction-cone penetrometer by pushing a cone with projection area 10 cm2 and 60o angle and standard velocity 20 mm per-second. 2 measurement parameters each 20 cm of depth: Cone Resistance (qc) Local Friction (fs) Electric friction-cone penetrometer measure the cone pressure and continuously friction with better accuracy level Bina Nusantara

113 CONE PENETRATION TEST (CPT)
ADVANTAGES Continuous Soil strength profile Give fast description of soil Simple LIMITATIONS Bad accuracy for soil with some stones Mechanical friction-cone penetrometer is less sensitive when applied in very soft clay Bina Nusantara

114 CPT CONE SIZE (ASTM D 3441) Bina Nusantara

115 ELECTRIC FRICTION-CONE PENETROMETER TIP
Bina Nusantara

116 EXAMPLE OF CPT GRAPH Bina Nusantara

117 FIELD VANE SHEAR TEST (FVT)
Measure undrained shear strength of soil Suitable for very soft clay to medium stiff clay Principle of equipment operation : vane pushed and rotated The vane shear equation : Correlation between vane shear and shear strength of soil Bina Nusantara

118 FIELD VANE SHEAR TEST (FVT)
Bina Nusantara

119 PRESSUREMETER TEST (PMT)
Measure the strength and deformation of soil Recommended use for the soil which need elastic settlement prediction Equipment mechanism : expanding the rubber cylinder of water by using air pressure Soil Types Limit Pressure (kN/m2) EM/pl Soft clay 50 – Firm clay – Stiff clay – 2, Loose silty sand 100 – Silt – 1, Sand and gravel 1,200 – 5, Till (Tanah liat berbatu) 1,000 – 5, Old fill – 1, Recent fill 50 – Bina Nusantara

120 PRESSUREMETER TEST (PMT)
Bina Nusantara

121 DILATOMETER TEST (DMT)
Have similar purpose and equipment mechanism with Pressuremeter The difference is in the pressure direction : DMT  one direction PMT  radial Bina Nusantara

122 DILATOMETER TEST (DMT)
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123 PLATE LOAD TEST Measure strength and deformation of soil
Use to determine bearing capacity of soil and its settlement especially for shallow foundation Work mechanism : push the circle/square plate at the certain depth with load of 2 – 3x design load until rupture Loading influence : 1.5 – 2x plate width Relationship to undrained shear strength: Su = (qu - t.H)/Nc qu = rupture load t = unit weight of soil H = thickness of soil on the sample surface Nc = bearing capacity factor Bina Nusantara

124 GROUND WATER INVESTIGATION
Purpose: Ground water elevation Seepage behaviour Method: Observation at bore hole Observation at observation well (standpipe) Measure using piezometer Seepage test at bore hole Pump test at bore hole Large scale of pump test Bina Nusantara

125 PIEZOMETER Bina Nusantara

126 PUMPING TEST Bina Nusantara

127 LABORATORY TESTS Soil Index (, , e, GS etc.) Shear Strength (c, )
Measurement of soil volume and mass Sieve analysis test Atterberg test Shear Strength (c, ) Triaxial Test (UU, CU, CD) Direct Shear Unconfined Compression Test Compresibility (Cc, Cv) Consolidation test Permeability (k) Constant Head Falling Head Bina Nusantara

128 EMPIRICAL CORRELATION
N-SPT value Sandy Soil Clayey or Silty Soil N-SPT Value Relative Density N-SPT Value Consistency 0 – 4 Very loose 0 – 2 Very soft 4 – 10 Loose 2 – 4 Soft 10 – 30 Medium 4 – 8 Medium stiff 30 – 50 Dense 8 – 15 Stiff > 50 Very dense 15 – 30 Very stiff > 30 Hard Bina Nusantara

129 EMPIRICAL CORRELATION
CPT value Bina Nusantara

130 EMPIRICAL CORRELATION
Between soil properties Cc = (LL – 10) C = qu/2 C = (19 – 23) CBR (C in kN/m2) Bina Nusantara


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