Lab Report: Falling Head Permeability Test

Geotechnical Engineering B
Lab Report

Student Name: Zhang Jie
Student Number: 33381954
Level: 6
Group: 4
Date: 2015.04.15
Lecturer: Steve Rogers
CONTENT
Constant Head permeability test 3
ABSTRACT 3
INTRODUCTION 3
EXPERIMENTAL PROCEDURE 4
CACULATIONS AND RESULTS 4
DISSCUSSION 5
CONCLUSIONS 5
Falling Head permeability test 6
ABSTRACT 6
INTRODUCTION
EXPERIMENTAL PROCEDURE 7
CACULATIONS AND RESULTS 8
DISSCUSSION 8
CONCLUSIONS 9
Consolidation test 9
ABSTRACT 9
INTRODUCTION 9
EXPERIMENTAL PROCEDURE 9
CACULATIONS AND RESULTS 10
DISSCUSSION 14
CONCLUSIONS 15
Triaxial test
INTRODUCTION
The falling head permeability test is a common laboratory testing method used to determine the permeability of fine grained soils with intermediate and low permeability such as silts and clay. This testing method can be applied to an undisturbed sample.
Theory
k= aLln(h1/h2)/A(t2-t1)
Table 2 is Schematic of a falling head permeameter (FHWA, 2011)

EXPERIMENTAL PROCEDURE
This test can be used for soils of low to intermediate permeability but its procedure is not included in BS1377.Water is allowed to flow down the stand pipe and through the sample so that the hydraulic head h at any time t is difference between the meniscus level in the standpipe and the overflow level. (Barnes, 2000)
CALCULTAIONS AND RESULTS
V=5.936 x 10-5 m3 a=5.936 x 10-5 m3/0.8m=7.42 x 10-5 m2
A=π0.012/4=7.854 x 10-3 m3
L=0.13 m
Test 1 a=7.42 x 10-5 m2
L=0.13 m h1=1.025 m h2=0.505 m
A=7.854 x 10-3 m3 t2=17.84 sec t1=0 sec k1=7.42 x 10-5m2 x 0.13m x ln2.0297 / 7.854 x 10-3m3 x 17.84sec k1=4.873 x 10-5 m/s

Test 2 a=7.42 x 10-5m2
L=0.13