DAR ES SALAAM INSTITUTE OF TECHNOLOGY

BUILDING AND CIVIL ENGINEERING DEPARTMENT

ORDINARY DIPLOMA IN BUILDING AND CIVIL ENGINEERING NTA LEVEL SIX

PROJEC TITLE: COMPARISON BETWEEN CONE PENETRATION METHOD AND CASAGRANDE METHOD ON THE CONSISTENCY LIMIT TESTS

STUDENT NAME: LUBETA HAMAD B.

ADMISSION NO: 110121141761

PROJECT TYPE: PROBLEM SOLVING

ACADEMIC YEAR: 2013/2014

INTRODUCTION The Atterberg limits are the basic measures of nature of grained soils. Depending on the water content of soils ; it may appear in four states, solid, semi-solid, plastic and liquid. In each state, the consistency and behaviour of the soil in different and consequently, so are its engineering propertis. Thus, the boundary between each state can be defined based on a change in soils behaviour.

Atterberg limits are extensively used for identification,description, and classification of cohesive soils and as a basis for preliminary assessment of their mechanical Properties.

Most of the comparison done between the methods used in soil laboratories for determination of liquid limits are based in their performing procedures, time used between each other and energy consumed.

PROBLEM STATEMENT Despite the significance role played by laboratory tests, little had been done to analyze the impact of comparison between cone penetration and casagrande methods in determination of liquid limits, the comparison done do not analyze the relationship between the results produced by both methods.

This project lies on comparison on results produced by cone penetration and casagrande methods if are equal or vice-versa, their similarities and differences between them.PROJECT OBJECTIVESvMAIN OBJECTIVEThe main objective of this project is to determine the relationship between cone penetration and casagrande methods in determination on the consistency Atterberg limit tests.vSPECIFIC OBJECTIVESTo conduct liquid limit tests of the same sample by both methods.To conduct plastic limit tests.Processing the results obtained by each method.Analyzing the results obtained by each method.Comparison of results obtained by both methods.

PROJECT SIGNIFICANCE The project is aimed to understand the relationship between cone penetration and casagrande methods on the results they produce in order to avoid the misunderstanding between them.SCOPE OF THE PROJECTThe project is based on comparison betweencone penetration and casagrande methods in determination of liquid limit, plastic limitAnd relationship between them.PROJECT QUESTIONSTo achieve the above main objective, the following questions have been set to guide the project.Is it true the casagrande give the results as the cone penetration?What are relationships between casagrande and cone penetration?What are difference between casagrande and cone penetrationMETHODOLOGYLiterature reviewData collectionData presentation and analysisConclusionRecommendationLITERATURE REVIEWThe objective of Atterberg limit tests is to obtain the liquid limit(LL) and plastic limit(PL), which are moisture contents that define the boundaries between material consistency states, these standardized tests produce comparable results for soil identification, classification and correlation strength.The liquid limit(LL) and plastic limit(PL) define the water content boundaries between non-plastic, plastic and viscous fluid states. The plastic index(PI) defines the complete range of plastic state.

CONTINUELiquid limit.

The liquid limit defines the boundary between plastic and viscous fluid states of the soil. It is determined by using standard liquid limit devices that are casagrande and cone penetrometer.

For casagrande device; the graph is plotted moisture content in(%) against the number blows, the moisture content corresponding to 25 number of blows defines the liquid limit.

CONTINUEFor cone penetrometer, the graph is drawn of cone penetration in(mm) against water content in(%) and the liquid limit of the soil is taken as water content corresponding to penetration of 20mm.

Plastic limit.The plastic limit defines the boundary between non-plastic and plastic states of the soil. It is determined simply by rolling a thread of soil and adjusting the moisture content until it breaks to 3mm diameter.

REFERENCESFundamental of soil behaviour(third edition) (James K. Mitchell & Kenichi Soga)Basic soil mechanics(fourth edition) (Roy Whitlow)Soil mechanics(second edition) (Graham Barnes)