Introduction.
Some definitions.
Mohr circle of stress.
Mohr-coulomb’s strength theory.
Tests for shear strength.
Shear tests based on drainage conditions.
Introduction.
Some definitions.
Mohr circle of stress.
Mohr-coulomb’s strength theory.
Tests for shear strength.
Shear tests based on drainage conditions.
Detailed content on shear strength of soils, principles of effective stresses, tests conducted to determine the shear strength of soils and its applications, dilatancy, thixotropy and sensitivity.
Geotechnical Engineering-II [Lec #3: Direct Shear Test)Muhammad Irfan
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Introduction
Geostatic Stresses
Boussinesq’s Equation
Vertical Stresses Under A Circular Area
Vertical Stresses Under A Rectangular Area
Equation Point Load Method
Newmark’s Influence Chart
This presentation is all about Shear Strength of Soil and it's importance in Civil Engineering, application of shear strength, direct shear test, mohr's circle, mohr's coulomb, shear strength, triaxial shear test, unconfined compression test, vane shear test
This presentation is all about consolidation of soil and it's importance in Civil Engineering, co-efficients of consolidation, methods of determining co-efficient of consolidation, Terzaghi's Spring Analogy, Terzaghi's Theory
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Lecture 11 Shear Strength of Soil CE240Wajahat Ullah
Shear Strength of Soil
Shear strength in soils
Introduction
Definitions
Mohr-Coulomb criterion
Introduction
Lab tests for getting the shear strength
Direct shear test
Introduction
Procedure & calculation
Critical void ratio
Detailed content on shear strength of soils, principles of effective stresses, tests conducted to determine the shear strength of soils and its applications, dilatancy, thixotropy and sensitivity.
Geotechnical Engineering-II [Lec #3: Direct Shear Test)Muhammad Irfan
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Introduction
Geostatic Stresses
Boussinesq’s Equation
Vertical Stresses Under A Circular Area
Vertical Stresses Under A Rectangular Area
Equation Point Load Method
Newmark’s Influence Chart
This presentation is all about Shear Strength of Soil and it's importance in Civil Engineering, application of shear strength, direct shear test, mohr's circle, mohr's coulomb, shear strength, triaxial shear test, unconfined compression test, vane shear test
This presentation is all about consolidation of soil and it's importance in Civil Engineering, co-efficients of consolidation, methods of determining co-efficient of consolidation, Terzaghi's Spring Analogy, Terzaghi's Theory
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Lecture 11 Shear Strength of Soil CE240Wajahat Ullah
Shear Strength of Soil
Shear strength in soils
Introduction
Definitions
Mohr-Coulomb criterion
Introduction
Lab tests for getting the shear strength
Direct shear test
Introduction
Procedure & calculation
Critical void ratio
shear strength
Angle of repose of sand
Coulomb's law of shear strength
Mohr circle of Stress
Determination of shear strength parameters of soils
Direct shear test
Triaxial Shear Test
Consolidated drained (CD) test
Unconfined Compression Test
Vane shear test
Static Cone Penetrometer Test
Standard Penetration Test (SPT)
Triaxial shear test and shear strength properties of soilsatish dulla
experiments to test the soil strength has given with illstrations. mainly concentrates on the most effective test, triaxial shear test along with brief introdction.
FOR MOVIES
http://movie-rulz.xyz/category/hollywood-movies/2016-english-movies/
http://movie-rulz.xyz/
http://movie-rulz.xyz/category/telugu-movies/2016-telugu-movies/
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
2. Types of Triaxial Tests
Is the drainage valve open?
yes no
Consolidated
sample
Unconsolidated
sample
Is the drainage valve open?
yes no
Drained
loading
Undrained
loading
Under all-around cell pressure c
cc
c
cStep 1
deviatoric stress
( = q)
Shearing (loading)
Step 2
c c
c+ q
3. Types of Triaxial Tests
Is the drainage valve open?
yes no
Consolidated
sample
Unconsolidated
sample
Under all-around cell pressure c
Step 1
Is the drainage valve open?
yes no
Drained
loading
Undrained
loading
Shearing (loading)
Step 2
CD test
CU test
UU test
4. Unconsolidated- Undrained test (UU Test)
Data analysis
C = 3
C = 3
No drainage
Initial specimen condition
3 + d
3
No drainage
Specimen condition
during shearing
Initial volume of the sample = A0 × H0
Volume of the sample during shearing = A × H
Since the test is conducted under undrained condition,
A × H = A0 × H0
A ×(H0 – H) = A0 × H0
A ×(1 – H/H0) = A0 z
A
A
1
0
5. Unconsolidated- Undrained test (UU Test)
Step 1: Immediately after sampling
0
0
= +
Step 2: After application of hydrostatic cell pressure
uc =B 3
C = 3
C = 3 uc
’3 =3 - uc
’3 =3 - uc
No drainage
Increase of pwp due to increase
of cell pressure
Increase of cell pressure
Skempton’s pore water
pressure parameter, B
Note: If soil is fully saturated, then B = 1 (hence, uc = 3)
6. Unconsolidated- Undrained test (UU Test)
Step 3: During application of axial load
3 + d
3
No drainage
ud =ABd
uc ± ud
= +
Increase of pwp due to increase of
deviator stress
Increase of deviator stress
Skempton’s pore water
pressure parameter, A
'
1 3 d c du u
'
3 3 c du u
7. Unconsolidated- Undrained test (UU Test)
Combining steps 2 and 3,
uc =B 3 ud =ABd
u=uc + ud
Total pore water pressure increment at any stage, u
u=B [3 + Ad]
Skempton’s pore
water pressure
equation
u=B [3 + A(1 – 3]
10. Relation between effective and total stress criteria
Three identical saturated soil samples are sheared to failure in UU triaxial tests. Each sample
is subjected to a different cell pressure. No water can drain at any stage. At failure the Mohr
circles are found to be as shown
t
13
11. Relation between effective and total stress criteria
Three identical saturated soil samples are sheared to failure in UU triaxial tests. Each sample
is subjected to a different cell pressure. No water can drain at any stage. At failure the Mohr
circles are found to be as shown
t
13
We find that all the total stress Mohr circles are the same size, and therefore fu = 0
and t = su = cu = constant
12. Relation between effective and total stress criteria
t
1313
Because each sample is at failure, the fundamental effective stress failure condition
must also be satisfied. As all the circles have the same size there must be only one
effective stress Mohr circle
t f c n' tan '
13. • The different total stress Mohr circles with a single effective
stress Mohr circle indicate that the pore pressure is different for
each sample.
• As discussed previously increasing the cell pressure without
allowing drainage has the effect of increasing the pore pressure
by the same amount (u = c) with no change in effective
stress.
• The change in pore pressure during shearing is a function of the
initial effective stress and the moisture content. As these are
identical for the three samples an identical strength is obtained.
Relation between effective and total stress criteria
14. • It is often found that a series of undrained tests from a
particular site give a value of fu that is not zero (cu not
constant). If this happens either
– the samples are not saturated, or
– the samples have different moisture contents
• If the samples are not saturated analyses based on
undrained behaviour will not be correct
• The undrained strength cu is not a fundamental soil
property. If the moisture content changes so will the
undrained strength.
Significance of undrained strength parameters
15. 3b 1b
Unconsolidated- Undrained test (UU Test)
Effect of degree of saturation on failure envelope
3a 1a3c 1c
t
or ’
S < 100% S > 100%
16. t t = in situ undrained
shear strength
Soft clay
1. Embankment constructed rapidly over a soft clay deposit
Some practical applications of UU analysis for clays
17. Some practical applications of UU analysis for clays
2. Large earth dam constructed rapidly with no change in
water content of soft clay
Core
t = Undrained shear strength of
clay core
t
18. 3. Footing placed rapidly on clay deposit
t = In situ undrained shear strength
Note: UU test simulates the short term condition in the field.
Thus, cu can be used to analyze the short term behavior of
soils
Some practical applications of UU analysis for clays
20. Unconfined Compression Test (UC Test)
1 = VC + f
3 = 0
Shearstress,t
Normal stress,
qu
Note: Theoritically qu = cu , However in the actual case qu < cu due
to premature failure of the sample
21. Other laboratory shear tests
Direct simple shear test
Torsional ring shear test
Plane strain triaxial test
22. Direct simple shear test
Torsional ring shear test
Plane strain triaxial test
Other laboratory shear tests
23. Direct simple shear test
Direct shear test
f = 80 mm
Soil specimenPorous
stones
Spiral wire
in rubber
membrane
Direct simple shear test
24. Direct simple shear test
Torsional ring shear test
Plane strain triaxial test
Other laboratory shear tests
29. Drained and undrained conditions
• DRAINED condition occurs when there is no change in pore water pressure
due to external loading
• In a drained condition, the pore water can drain out of the soil easily,
causing volumetric strains in the soil
• UNDRAINED condition occurs when the pore water is unable to drain out of
the soil
• In undrained condition the rate of loading is much quicker than the rate at
which the pore water is able to drain out of the soil
• As a result, most of the external loading is taken by the pore water,
resulting in an increase in the pore water pressure.
• The tendency of soil to change in volume is suppressed during undrained
loading.
30. Drained and undrained conditions
• The existence of either a drained or an undrained condition in a soil
depends on: ((i)soil types; fine-grained or coarse grained, (ii) geological
formation and (iii) rate of loading)
• For a rate of loading associated with a normal construction activity,
saturated coarse grained soils (e.g. sands and gravel) experience drained
conditions and saturated fine-grained soils (e.g. silts and clays) experience
undrained conditions
• If the rate of loading is fast enough (e.g. during an earthquake), even
coarse-grained soils can experience undrained loading, often resulting in
liquefaction.
31. Example of undrained loading (Liquefaction)
When loading is rapidly applied and large enough such that it does not flow out in time
before the next cycle of load is applied, the water pressure may build to an extent where
they exceed the contact stresses between the grains of soil that keep them in contact
with each other. These contact between grains are the means by which the weight of the
buildings and overlying soil layers are transferred from the ground surface to layers of
soil or rock at greater depth. This loss of soil structure causes it to lose all of its strength
and it may be observed to flow like a liquid.
32. Example of undrained loading (Liquefaction)
Uplift of sewerage during
Niigata earthquake 2004
Collapse of flat house during
the 1964 Niigata earthquake,
Japan.
33. Drained and undrained conditions
• The shear strength of a fine-grained soil under undrained condition is called
the undrained shear strength and denoted as su.
• su is the radius of the Mohr’s circle of total stress:
τ
σ, σ’ 1 f
3 f
us
1 3
2
f f
us
• The undrained shear strength
depends only on the initial void
ratio or the initial water content of
the soil
Total stress circle
34. Drained and undrained conditions
• The undrained shear strength is not a fundamental soil parameter.
• Its value depends on the values of the initial confining stresses.
τ
σ, σ’
• An increase in initial
confining stresses causes a
decrease in void ratio and
an increase in undrained
shear strength
1us
2us
1 f
3 f
1 f
3 f
35. Selection of shear strength parameter – Drained or
undrained ?
CU with pore
water pressure
measurement
36. Drained and Undrained shear strength
Condition Drained Undrained
Excess porewater pressure Not zero; could be positive or
negative
Volume change Compression Positive excess porewater pressure
Expansion Negative excess porewater pressure
Consolidation Yes, fine grained soil No
Compression Yes Yes, but lateral expansion must occur
so that the volume change is zero
Analysis Effective stress (EFA) Total stress (TSA)
Design parameters
0
uS' '
(or )cs pf f
Homework: Do reading from page 243 – 245 (Section 7.8) – Soil mechanics and foundations
When designing a geotechnical structure, both
undrained and drained conditions must be considered
to determine which one is more critical