Consolidation Test On Cohesive Soil

Geotechnical Engineering Laboratory

Sub By: Farhad Raoofi

ASTM-D 2435

DATE: 07-04-2016

Herat, Afghanistan

Ultra Design And research Company

Class Outlines

Consolidation

Definition & Introduction

Type of Consolidations

One – Dimensional Consolidation Test

Definitions

Procedure

Graphs and results

Consolidation refers to the compression o

settlement that soil undergo As response of

placing loads on to the ground

These loads produce corresponding increases

in the vertical effective stress

Consolidation is a time- dependent process in

some soils it may take long time ( 100 years ? )

to achieve complete settlement.

Consolidation – Definitions

Consolidation ( Cont. )

During consolidation pore water or the water

voids of saturated clay gets squeezed out –

reducing the volume of the clay _ hence causing

settlement called as consolidation settlement

The spring

analogy to

consolidation

Consolidation ( Cont. )

Types Of Consolidation

There are three types of consolidation:

Immediate consolidation; caused by elastic deformation of dry soil

or moist and saturated soil without change in moisture content

Primary consolidation; caused as a result of volume change in

saturate cohesive soils due to exclusion of water occupied the void

spaces

Secondary consolidation; occurs in saturated cohesive soils as a

result of the plastic adjustment of soil fabrics

Two types of consolidometer ( odometer ) commonly used

Consolidation Test:

Floating – ring

Fixed ring

This lab uses fixed ring consolidometer

ASTM 2435

Laboratory Consolidation Test

Consolidation Test

Laboratory Consolidation Test

Procedure:

Calculation: