NORTHEASTERN UNIVERSITY
Department of Civil and Environmental Engineering
Advanced Foundation Engineering
CIVE 7302
SPRING 2012
Instructor:
Professor M .K. Yegian
401 Snell Engineering
Tel: (781)-910-6680 (cell-anytime)
e-mail: myegian@neu.edu
Text:
1)
“Principles of Foundation Engineering” Seventh Edition
By: Braja M. Das
2)
Supplemental Class Notes
Course Outline
TOPIC 1 INTRODUCTION TO FOUNDATION ENGINEERING
1.1
Example Foundation Designs
TOPIC 2 REVIEW OF SOIL MECHANICS (Chapter 1 Das)
2.1
2.2
2.3
2.4
Index and Soil Classification
Example (Soil Classification)
Soil Structure
Effective Stress Calculations
Example (Effective Stress Calculations)
Shear Strength of Soils
2.4.1
2.4.2
2.4.3
Shear Strength of Sands
Example (Laboratory Determination of Friction Angle)
Shear Strength of Clays
Summary Notes on Shear Strength of Clays
TOPIC 3 SUBSURFACE EXPLORATION (Chapter 2 Das)
3.1
3.2
3.3
Purpose of Subsurface Exploration
Subsurface Exploration Program
Procedures for Site Investigation
3.4
Example (Rock Cores)
Example (Test Pit)
Subsurface Exploration Report
Example (Subsurface Exploration Program)
TOPIC 4 SALLOW FOUNDATIONS: ULTIMATE BEARING CAPACITY
(Chapters 3 and 4 Das)
4.1
4.2
4.3
4.4
4.5
Types of Shallow Foundations
General Concept
Terzaghi’s Bearing Capacity Theory
The General Bearing Capacity Equation
Summary of Bearing Capacity Procedure
4.5.1
4.5.2
Terzaghi’s Approach
4.5.1.1 Cohessionless Soils C = 0,  = 
4.5.1.2 Cohessive Soils (Clays)
Drained Loading, Long-Term Analysis, Effective Stress
Analysis, C = C, and  = 
4.5.1.2 Cohessive Soils (Clays)
Undrained Loading, Short-Term Analysis, Total Stress
Analysis, C = Su, and  = 
General Bearing Capacity Equations
4.5.2.1 Cohessionless Soils (Sands), C = 0,  = 
Cohessive Soils (Clays)
Drained Loading, Long-Term Analysis, Effective Stress
Analysis, C = C, and  = 
4.5.2.3 Cohessive Soils (Clays)
Undrained Loading, Short-Term Analysis, Total Stress
Analysis, C = Su, and  = 


4.6
Factor of Safety Against Bearing Capacity Failure
Example (Bearing Capacity)
Foundations with One-Way Eccentricity
Example (Stresses under Eccentric Loads)
Presumptive Bearing Pressures
4.7
4.8
4.9
Ultimate Bearing Capacity: Special Cases
4.9.1 Rigid Base at Shallow Depth
4.9.2 Closely Spaced Foundations
4.9.3 Footings on Bedrock
TOPIC 5 SETTLMENT OF SHALLOW FOUNDATIONS (Chapter 5 Das)
5.1
Stresses below a Rectangular Foundation
5.1.1
5.1.2
5.2
5.3
5.4
5.5
Schmertmann’s Method for Settlement on Sand
Example (Schmertmann’s Method for Settlement on Sand)
Settlement on Sand Based on SPT (Meyerhof’s Method)
Example (Settlement on Sand Based on SPT (Meyerhof’s Method)
Estimation of Es, Modulus of Elasticity of Soil
Settlement on Clays
5.5.1
5.5.2
5.5.3
5.5.4
5.6
Simple Approximate Approach (2:1 Method)
Use of Charts
Example (Stress Distribution)
Compressibility of Clay and Consolidation Settlement
5.5.1.1 Field Conditions
5.5.1.2 Laboratory Tests
5.5.1.3 Primary Consolidation Settlement
5.5.1.3.1 Normally Consolidated Clay Settlement
Example (Primary Consolidation Settlement)
Time Rate of Consolidation Settlement
Example Time Rate of Consolidation Settlement
Precompression with Surcharge
Sand Drains (Strip Drains, Wick Drains)
Tolerable Settlement of Buildings
TOPIC 6 BEARING CAPACITY OF MAT FOUNDATIONS (Chapter 6 Das)
6.1
6.2
6.3
Typical Combined Footings and Mat Foundations
Bearing Capacity of Mat Foundations
Compensated (Floating) Foundations
Example (Compensated (Floating) Foundations)
TOPIC 7 DEEP FOUNDATIONS (Chapter 11 Das)
7.1
7.2
7.3
7.4
Typical Piles, Drilled Piers, and Caisson Foundations
Sources of Pile Capacity
Estimating Pile Length
Estimating Pile Axial Capacity
7.4.1
7.4.2
7.4.3
7.4.4
7.4.5
7.5
General Approach
Meyerhof’s Method for Qp
Frictional Resistance Qs
Point Bearing Capacity on Rocks
Settlement of Single Pile
Estimating Pile Lateral Capacity
Example (Pile Foundation)
7.6
7.7
7.8
7.9
7.10
7.11
Pile Group Efficiency
Ultimate Capacity of Group Pile in Saturated Clays
Consolidation Settlement of Group Piles
Pile Driving Formula
Negative Skin Friction (Downdrag)
Drilled Shaft
7.11.1 Drilled Shaft Types and Construction
7.11.2 Load Transfer Mechanism
7.11.3 Load-Bearing Capacity
7.11.3.1
In Granular Soils
7.11.3.2
In Clays
7.11.3.3
Into Bedrock
7.11.3.4
FHWA’s Empirical Methods
TOPIC 8 SOIL-PILE INTERACTION ANALYSIS
8.1
8.2
Analysis of a Group of Pile Subjected to Axial and Lateral Loading
Application of GROUP 7.0
Example (Soil-Pile Interaction Analysis)
Topics 9 and 10 will be covered if time permits
TOPIC 9 LATERAL EARTH PRESSURES (Chapter 7 Das)
9.1
9.2
9.3
9.4
Earth Pressure Conditions
Lateral Earth Pressure at-Rest
Rankine Active Earth Pressure
Rankine Passive Earth Pressure
TOPIC 10 RETAINING WALLS (Chapter 8 Das)
10.1
10.2
10.3
Types of Earth Retaining Structures
Proportioning of Gravity and Cantilever retaining Walls
Stability of Retaining Walls
10.1.1 Check Overturning
10.1.2 Check for Bearing Capacity Failure
10.1.3 Check “Global” Slope Instability
Example (Stability of Retaining Wall)
10.4
Control of Water Table in Soil Backfill
Grade for the Course
12-
Assignments
Final Examination
(70%)
(30%)
Points
Assignment Problem 1 Problem 2 Problem 3 Problem 4
1
3
7
2
2
1
4
3
3
5
5
4
2
6
2
5
10
6 (Time Permitting)
5
5
Total
10
10
10
10
10
10
Weight
0.15
0.2
0.25
0.15
0.25
0.05
Total Assignment Score
Total Assignment Grade %
Score
1.5
2
2.5
1.5
2.5
0.5
10.5
105
References
1-
Das, B. M. (2011) “Principles of Foundation Engineering” Seventh Edition,
Thomson.
2-
Day, R. W. (2006) “Foundation Engineering Handbook” McGraw-Hill
3-
GROUP- Analysis of a Group of Piles Subjected to axial and lateral Loading,
ENSOFT, Inc.
4-
McCarthy, D. F. (2007) “Essentials of Soil Mechanics and Foundations” Seventh
Edition, Prentice Hall.