Geotechnics

Module aims

  • To introduce students to slope stability analysis, foundation design and retaining wall design. Firstly the theoretical basis of geotechnical design will be introduced.
  • Then, also drawing on the material covered in the CI1-150 and CI2-250, the student will develop the ability to assess slope stability and design retaining walls and foundations for realistic situations. The concept of factor of safety, as applied in geotechnical engineering, will be introduced.
  • Reference will also be made to limiting soil-structure deformations to acceptable levels.

Learning outcomes

On successfully completing this course unit, students will be able to:

  • Design a shallow foundation in drained and undrained conditions.
  • Describe stress distributions beneath shallow foundations and estimate settlements.
  • Estimate pile capacity using empirically derived equations.
  • Calculate horizontal (lateral) earth pressures.
  • Design gravity and sheet pile retaining walls.
  • Design deep excavations.
  • Describe and classify landslides.
  • Complete stability analysis for drained and undrained conditions on failure surfaces of planar, circular and general shapes.

Module syllabus

Foundations (Dr O’Sullivan) (10 hours mixed lectures and tutorials)  

  • Laboratory session to explore foundation failure mechanism.
  • Shallow foundations theoretical solutions for shallow foundation capacity and their adaptation for use in practical design for drained and undrained conditions.
  • Settlement of foundations, including stress distribution.
  • Discussion on best practice in calculating pile capacity and design of single and group piles.

Slopes (Dr Kontoe) (10 hours mixed lectures and tutorials)                     

  • Geomorphological and Geotechnical Classification of slope failures.
  • Introduction of Limit Equilibrium method and factor of safety definition.
  • Limit Equilibrium analysis of planar, rotational and compound slides.
  • Comparison of methods of slices.
  • Factors affecting slope stability analysis (tension cracks, vegetation, seismic loading).

Earth pressures and retaining structures (Professor Jardine) (10 hours mixed lectures and tutorials)

  • At-rest, active and passive earth pressure conditions (Jaky, Rankine).
  • Model wall experiments.
  • Wall friction, analyses of Coulomb, Caquot and Kerisel.
  • Problems in clay (drainage conditions, vertical cuts, tension cracks, flow nets etc.).
  • Design of gravity structures.
  • Sheet pile wall design and ground anchor design.
  • Deep excavations, strut loads, base heave and ground movements.
  • The content of this module will link with a two-day geotechnical mini-project to be held in the summer term – see module CI3-312; this module is a key prerequisite for CI3-312.

No.

Topic

Staff

01

Introduction to foundations

Shallow foundations – stability analysis

COS

02

Shallow foundations – stability analysis and settlement

COS

03

Piled foundations

COS

04

Classification of mass movement and slope stability analysis introduction

SK

05

Slope stability analysis methods

SK

06

Geotechnical considerations for slope stability analysis

SK

07

Introduction. At rest, active and passive earth pressures, Rankine and Coulomb theory; model test

RJJ

08

General wedge and Caquot & Kerisel theory. Design for gravity retaining walls

RJJ

09

Earth pressures and design for slender retaining walls, beam/plate ground anchors and deep excavations

RJJ

10

Revision classes          

SK, COS


Pre-requisites

CI1-150, CI2-250, CI3-312 

Teaching methods

This module is taught using formal lectures, tutorials and there is a one-hour laboratory session. There is a revision test on year 1 and year 2 material (CI-150 and CI-250) at the start of the module.

Assessments

Assessment information will be provided separately.

Reading list

Module leaders

Professor Catherine O'Sullivan