INTRODUCTION Session 1 – 2 Course : S0825/Foundation Engineering Year : 2009 INTRODUCTION Session 1 – 2
GENERAL SCOPE OF THE COURSE Introduction (Definition, type of foundation, review of Soil Mechanics Principles) Bearing Capacity of Soil Shallow foundations (type, design and settlement of foundation) Sheet Pile Structure (lateral earth pressure, design of sheet pile) Deep Foundation (Single pile, Group pile, settlement of pile) Installation of pile and test of pile capacity Application of shallow, deep foundation and sheet pile structure Bina Nusantara
GENERAL Grading Policy Home Work ………........................ 20% Mid Semester Test ………………. 30% Final Test ….................................. 50% TOTAL ..................... 100% Note: Appropriate changes to this grading policy may be made with student consent. Bina Nusantara
REFERENCE TEXTBOOK Bina Nusantara
REFERENCE TEXTBOOK SUPPORTING TEXTBOOK Bina Nusantara
COURSE 1 Content: Definition Design Criteria Soil investigation, laboratory tests and soil properties related to structure designs Bina Nusantara
What is Foundation Engineering? DEFINITION What is Foundation Engineering? The art of selecting, designing, and constructing structural support systems based on scientific principles of soils and engineering mechanics incorporating accumulated experience with such applications. A scientifically Acceptable Answer Bina Nusantara
What is Foundation Engineering? DEFINITION What is Foundation Engineering? Foundation Engineering is the art and science of molding materials we do not fully understand into shapes we can not precisely analyze to resist forces we can not accurately predict, all in such a way that the society at large is given no reason to suspect of our ignorance. Not so scientifically Acceptable Answer – addopted from Coduto Bina Nusantara
Retaining Structure Bina Nusantara
FOUNDATION TYPES Shallow Foundations. Shallow foundations are usually placed within a depth D beneath the ground surface less than the minimum width B of the foundation. Shallow foundations consist of spread and continuous footings, wall footings and mats. Bina Nusantara
FOUNDATION TYPES Deep Foundations. Deep foundations can be as short as 15 to 20 ft or as long as 200 ft or more and may consist of driven piles, drilled shafts or stone columns. A single drilled shaft often has greater load bearing capacity than a single pile. Deep foundations may be designed to carry superstructure loads through poor soil (loose sands, soft clays, and collapsible materials) into competent bearing materials. Even when piles or drilled shafts are carried into competent materials, significant settlement can still occur if compressible soils are located below the tip of these deep foundations. Bina Nusantara
DESIGN CRITERIA THE DESIGN SHOULD BE: SAFE RELIABLE DURABLE BUILDABLE ECONOMIC Bina Nusantara
DESIGN DATA SOIL DATA GROUND WATER DATA GEOMETRY DATA DATA OF LOAD Bina Nusantara
SOIL DATA DETERMINED FROM: FIELD INVESTIGATION LABORATORY TEST CPT SPT VANE SHEAR TEST PRESSUREMETER TEST LABORATORY TEST INDEX TEST TRIAKSIAL DIRECT SHEAR UNCONFINED CONSOLIDATION Bina Nusantara
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 fall height of hammer Bina Nusantara
HAMMER OF SPT Bina Nusantara
DIMENSION OF SPT TUBE Bina Nusantara
SPT EXECUTION Bina Nusantara
SPT PROFILE (EXAMPLE) Bina Nusantara
CONE PENETRATION TEST (CPT) TYPES OF TOOL 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
CONE PENETRATION TEST (CPT) ADVANTAGES Continuous Soil strength profile Give fast description of soil Simple LIMITATION The accuracy is bad for soil with some stones Mechanical friction-cone penetrometer is less sensitive when applied in very soft clay Bina Nusantara
CONE DIMENSION (ASTM D3441) Bina Nusantara
ELECTRIC CONE DIMENSION Bina Nusantara
CPT RESULT (EXAMPLE) Bina Nusantara
LABORATORY TESTS Soil Index (, , e, GS dll.) Measuring of volume and mass of sample Sieve analysis test Atterberg Test Shear Strength of Soil (c, ) Triaksial Test (UU, CU, CD) Direct Shear Unconfined Compression Test Compressibility (Cc, Cv) Consolidation Test Permeability (k) Constant Head Falling Head Bina Nusantara
EMPIRICAL CORRELATION SPT Data Sandy Soil Clay or Silt N-Value Relative Density 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
EMPIRICAL CORRELATION CPT Data Bina Nusantara
EMPIRICAL CORRELATION Between Soil Properties Cc = 0,009 (LL – 10) Cu = qu/2 Cu = 19 – 23 CBR (C in kN/m2) Bina Nusantara