Soils and rocks have unique and distinct engineering properties.
Engineering properties of soils and rocks are very essential parameters to be analysed for several technical reasons.
Properties of these materials may not only pose problems but also give solutions to solve the problems.
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.
Engineering properties of soil comprises of physical properties, index properties, strength parameters (shear strength parameters), permeability characteristics, consolidation properties, modulus parameters, dynamic behavior etc. This module highlights most of the engineering properties of soils.
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.
Some definitions.
Mohr circle of stress.
Mohr-coulomb’s strength theory.
Tests for shear strength.
Shear tests based on drainage conditions.
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.
Engineering properties of soil comprises of physical properties, index properties, strength parameters (shear strength parameters), permeability characteristics, consolidation properties, modulus parameters, dynamic behavior etc. This module highlights most of the engineering properties of soils.
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.
Some definitions.
Mohr circle of stress.
Mohr-coulomb’s strength theory.
Tests for shear strength.
Shear tests based on drainage conditions.
SOIL COMPACTION AND ITS EFFECT ON PROPERTIESGeorgeThampy
soil compaction occurs when soil particles are pressed together so that reduction in pore space between them.soil compaction increases the shear strength of the soil.And soil compaction is much effective in earth dams.
Study Of Soil Parameters Under Design Of Fexible PavementArif Siddiqui
The soil parameters which are required to be analysed before doing any excavation is shown in this presentation.
This presentation is basically study based.
Thank you
Er. Arif Mohd Siddiqui
Experiential Investigation on the Stabilization of Dispersive Soil with Limeijtsrd
The soils that are highly susceptible to erosion and containing high percentage of exchangeable sodium ions are called Dispersive Soils. In appearance, dispersive clays are like normal clays that are stable and somewhat resistant to erosion, but in reality they can be highly erosive and subject to severe damage or failure. Using dispersive clay soils in hydraulic structures, embankment dams, or other structures such as roadway, embankments can cause serious engineering problems if these soils are not stabilized and used appropriately. This problem is worldwide, and structural failures attributed to dispersive soils have occurred in many countries. This paper presents the stabilization of dispersive soil with lime. The soil sample is taken from Mandalay. Grain size distribution, Atterberg's limit test, compaction test, unconfined compressive strength UCS test and triaxial test are carried out to obtain the properties of soil. Type of studied soil classified by unified classification system is lean clay with sand. Crumb test is performed to know the dispersion degree of study soil. According to crumb test, the study soil is highly dispersive clay soil. Lime is used as stabilizing agent. The amount of lime used is 2 , 3 and 4 by dry weight of soil. The studied soil is mixed various contents of lime, and then crumb test is performed. At dispersive soil mixed with 4 of lime, there is no dispersion characteristic in soil. For stabilization of studied soil, 4 of lime is selected to investigate the improvement of strength in treated soil. The treated soil is performed compaction test, unconfined compression strength UCS test and triaxial test. Unconfined compression strength of treated soil at 4 lime is increased as 1.12 times that of natural soil. The shear strength of treated soil increases about 2 times than that of natural soil. The cohesion value of treated soil increases about 1.12 times and the angle of internal friction increases about 1.23 times than that of natural soil. Finally, it is concluded from this study that the lime treated soil is more resistant to erosion and the treated soil is more resistant to shear stress and lateral pressure. Soe Soe War | Nyein Nyein Thant "Experiential Investigation on the Stabilization of Dispersive Soil with Lime" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26658.pdfPaper URL: https://www.ijtsrd.com/engineering/civil-engineering/26658/experiential-investigation-on-the-stabilization-of-dispersive-soil-with-lime/soe-soe-war
Fundamentals of Soil Mechanics and ConcreteDenis Koval
Training Fundamentals on Soil Mechanics & Concrete by GLobal Construction
including:
- Soil Types
- Types of Soil Compaction
- Compact Soils
- Soil Gradation
- Soil Moisture Content
- Atterberg Limits Test
- Laboratory & Field Compaction Tests
- Types of Compaction Equipment
E-content is a Comprehensive package of teaching material put into hypermedia format. Hypermedia is multimedia with internet deplorability. E-content can not be created by a teaching faculty alone . It needs the role of teacher, Video editor, production assistants, web developers (HTML 5 or Adobe captivate, etc). Analyze the learner needs and goals of the instructional material development, development of a delivery system and content, pilot study of the material developed, implementation, evaluating, refining the materials etc. In designing and development of E-content we have to adopt one of the instructional design models based on our requirements.
Pedagogy is the most commonly understood approach to teaching. It refers to the theory and practice of learning. Pedagogy is often described as the act of teaching. Pedagogy has little variations between traditional teaching and online teaching. Online teaching pedagogy is a method of effective teaching practice specifically developed for teaching via the internet. It has a set of prescribed methods, strategies, and practices for teaching academic subjects in an online (or blended) environment, where students are in a physical location separate from the faculty member.
Technology has changed the possibilities within teaching and learning. Classes, which prior to the digital era were restricted to lectures, talks, and physical objects, no longer have to be designed in that manner. Training in a synchronous virtual classroom can only be successful with the active participation and engagement of the learners. Explore the Virtual Classroom’s features and see how they can support and enhance your tutoring style.
• The monitoring and evaluation of the institutional processes require a carefully structured system of internal and external review. The NAAC expects the Institutions to undertake continuous Academic and Administrative Audits (AAA). This presentation is intended to serve as advisory to all accredited HEIs who volunteer to undertake AAA. The pros and cons of this process are also highlighted. Academic and Administrative Audit is the process of evaluating the efficiency and effectiveness of the administrative procedure. It includes assessment of policies, strategies & functions of the various administrative departments, control of the overall administrative system, etc. This checklist gives an overview what the audit committee members may look into while visiting an institution for this purpose. It invariably follows the Quality Indicators Framework prescribed by Accreditation Council in India.
• The monitoring and evaluation of the institutional processes require a carefully structured system of internal and external review. The NAAC expects the Institutions to undertake continuous Academic and Administrative Audits (AAA). This presentation is intended to serve as advisory to all accredited HEIs who volunteer to undertake AAA.
Chemical analysis data of water samples can not be used directly for understanding. They are to be used for various calculations in order to determine the quality parameters that have a lot of significances. A. Balasubramanian and D. Nagaraju, of the Department of Studies in Earth Science, Centre for Advanced Studies, University of Mysore, Mysore-570006, Karnataka, India have recently brought out a software and its application manual as a good book for reference and execution. The Name of the software is WATCHIT meaning Water Chemistry Interpretation Techniques. This software computes more than 100 parameters pertaining to water quality interpretations. The software follows its own method of approach to determine the required results. Systems International Units are used. Limited input parameters are required. This is suitable for all scientific research, government water quality data interpretations and for understanding the quality of water before using it.
Water conservation refers to reducing the usage of water and recycling of waste water for different purposes like domestic usage, industries, agriculture etc. This technical article highlights most of the popular methods of water conservation. A special note on rainwater harvesting is also provided.
This module gives an overview of general applications of current hydrogeological aspects. It is for the basic understanding of students and research scholars.
Climate Extreme (extreme weather or climate event) refers to the occurrence of a value of a weather or climate variable above (or below) a threshold value near the upper (or lower) ends of the range of observed values of the variable. Extreme weather and climate events, interacting with exposed and vulnerable human and natural systems, can lead to disasters.
WATER RESOURCES PLANNING AND MANAGEMENT POSSIBILITIES IN CHAMARAJANAGAR TALUK...Prof. A.Balasubramanian
Any unplanned development and utilization of water resources with result in water scarcity. In many parts of the developing world. Such a situation exists. In order to do proper planning and
management of water resources, it is necessary to conduct detailed analyses of the factors, which influence the water availability and its uses. In the present study, a comprehensive analysis have been undertaken for proper utilization of water resources in Chamarajanagar Taluk, which has been identified as one of the drought hit districts of Karnataka, in India. The factors analysed in this work are, surface and groundwater availability, land use, cropping pattern, recharge potential of soils and the rainfall pattern in typical areas of Taluk. It is observed that the problem of water scarcity is mainly due to the lack of irrigation planning and management. Hence, a
modified cropping pattern is suggested by taking into consideration of all available water resources and other conditions.
In broad terms, cultural geography examines the cultural values, practices, discursive and material expressions and artefacts of people, the cultural diversity and plurality of society.
It also emphasizes on how cultures are distributed over space, how places and identities are produced, how people make sense of places and build senses of place, and how people produce and communicate knowledge and meaning.
Minerals are formed by changes in chemical energy in systems which contain one fluid or vapor phase. In nature, minerals are formed by crystallisation or precipitation from concentrated solutions. These solutions are called as ore-bearing fluids. Ore-bearing fluids are characterised by high concentration of certain metallic or other elements.
Fluids are the most effective agents for the transport of material in the mantle and the Earth's crust.
Soils are complex mixers forming the skin of the earth's surface. Soil is a dynamic layer in which many complex chemical, physical and biological activities are going on constantly. Soils become adjusted to conditions of climate, landform and vegetation, and will change internally when those controlling conditions change. Soils are products of weathering. Soils play a dominant role in earth's geomorphic processes in a cyclic manner. The characteristics of soils are very essential for several reasons. This module highlights these characteristics.
GIS TECHNIQUES IN WATER RESOURCES PLANNING AND MANAGEMENT IN CHAMARAJANAGAR ...Prof. A.Balasubramanian
The over-exploitation and contamination of groundwater continue to threaten the long-term sustainability of our precious water resources, in spite of the best efforts made by various agencies.
This has many serious implications to the economic development of a country like India. Lack of
judicious planning and integration of environmental consideration to ground water development
projects are primarily responsible for such a state of affair in the ground water sector. Geographical Information Systems could be of immense help in planning sustainable ground water management strategies, especially in hard rock areas with limited ground water potential. Data collected from
Satellite Imagery and through field investigations have been integrated, on a GIS platform, for demarcation and prioritization of areas suitable for ground water development and ground water augmentation. An attempt has also been made to assess the vulnerability of the area to ground water
contamination. This paper demonstrates the utility of GIS in planning judicious management of ground water resources in a typical hard rock area of Chamarajanagar Taluk, Karnataka, state India.
Nanobiomaterials are very effective components for several biomedical and pharmaceutical studies. Among the metallic, organic, ceramic and polymeric nanomaterials, metallic nanomaterials have shown certain prominent biomedical applications. Enormous works have been done to synthesize, analyse and administer the metallic nanoparticles for various kinds of medical and therapeutic applications, during the last forty years. In these analyses, the prominent biomedical applications of ten metallic nanobiomaterials have been reviewed from various sources and works. It has been found that almost nine of them are used in a very wide spectrum of medical and theranostic applications.
A variety of Nano-biomaterials are synthesised, characterised and tested to find out their potentialities by global scientific communities, during the last three decades. Among those, nanostructured ceramics, cements and coatings are being considered for major use in orthopaedic, dental and other medical applications. The development of novel biocompatible ceramic materials with improved biomedical functions is at the forefront of health-related applications, all over the world. Understanding of the potential biomedical applications of ceramic nanomaterials will provide a major insight into the future developments. This study reviews and enlists the prominent potential biomedical applications of ceramic nanomaterials, like Calcium Phosphate (CaP), Tri-Calcium Phosphate (TCP), Hydroxy-Apatite(HAP), TCP+HAP, Si substituted HAP, Calcium Sulphate and Carbonate, Bioactive Glasses, Bioactive Glass Ceramics, Titania-Based Ceramics, Zirconia Ceramics, Alumina Ceramcis and Ceramic Polymer Composites.
The present forest and tree cover of the country is 78.37 million ha in 2007 which is 23.84% of the geographical areas and it includes 2.82% tree cover. This becomes 25.25%, if the areas above tree line i.e., 4000m are excluded from the total geographical area. The forest cover is classified into 3 canopy density classes.
1. Very Dense Forest (VDF) with canopy density more than 70%
2. Moderately Dense Forest (MDF) with Canopy density between 40-70% and
3. Open Forest (OF) with Canopy density between 10-40%
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
Thanks...!
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
PRESENTATION ABOUT PRINCIPLE OF COSMATIC EVALUATION
Geotechnical properties of soils
1. 1
GEOTECHNICAL PROPERTIES OF SOILS
by
Prof. A. Balasubramanian
Centre for Advanced Studies in Earth Science
University of Mysore
Mysore-6
2. 2
Introduction: Soils and rocks have unique and
distinct engineering properties.
Engineering properties of soils and rocks are
very essential parameters to be analysed for
several technical reasons.
Properties of these materials may not only pose
problems but also give solutions to solve the
problems.
3. 3
Foundation and construction engineering,
structural engineering and excavation works for
various projects need a thorough investigations
of soils and their properties.
Engineering properties of soils:
Soils are loose fragments of organic and
inorganic constituents.
They possess typical physical, chemical,
engineering and biological properties.
4. 4
Soils are also characterised by their
mechanical properties,
index properties,
strength parameters (shear strength
parameters),
permeability characteristics,
consolidation properties,
modulus parameters, dynamic behavior, etc.
Sometimes these are called as geotechnical
properties.
5. 5
1. Soil texture and soil structure:
Both are unique properties of the soil that will
have a profound effect on the behavior of soils.
2. Specific Gravity :
The specific gravity of soil, Gs, is defined as the
ratio of the unit weight of a given material to the
unit weight of water.
6. 6
3. Bulk density:
Bulk density is the weight of soil in a given
volume.
Bulk density is dependent on soil texture and the
densities of soil mineral (sand, silt, and clay) and
organic matter particles, as well as their packing
arrangement.
Bulk density increases with compaction and
tends to increase with depth.
7. 7
Sandy soils are more prone to have high bulk
density.
Bulk density can be used to calculate soil
properties per unit area (e.g. kg/ha).
Bulk density is not an intrinsic property of a
material; it can change depending on how the
material is handled.
8. 8
The bulk density of soil depends greatly on the
mineral make up of soil and the degree
of compaction.
Bulk density typically increases with soil depth.
High bulk density is an indicator of low soil
porosity.
When eroded soil particles fill pore space,
porosity is reduced and bulk density increases.
Cultivation can result in compacted soil layers
with increased bulk density.
9. 9
a) Calculate the bulk density of a 400 cm3 soil
sample that weighs 575 g (oven dry weight).
r b = Ms/Vs = 575g/400cm3
= 1.44g/ cm3.
.
10. 10
b) Calculate the bulk density of a rectangular soil
sample with dimensions 12 cm by 6 cm by 4 cm,
that is 15% moisture content and weighs 320 g.
Vol. of soil = 12cm x 6cm x 4cm = 288cm3
Oven dry wt. = 320/1.15 = 272g.
r b = 272/288 = 0.97g/cm3
Bulk density influence water infiltration and
plant root health.
11. 11
4. Cohesion:
Cohesive soil means clay (fine grained soil), or
soil with a high clay content, which has cohesive
strength.
Cohesive soil does not crumble, can be
excavated with vertical sideslopes, and is plastic
when moist.
Cohesive soil is hard to break up when dry, and
exhibits significant cohesion when submerged.
12. 12
Cohesive soils include clayey silt, sandy clay, silty
clay, clay and organic clay.
It reflects the internal molecular
attraction(binding capacity) which resists the
rupture or shear(looseness) of a material.
Cohesion is derived in the fine grained soils from
the water films which bind together the
individual particles in the soil mass.
13. 13
The soil cohesion depends strongly on the
consistence, packing, and saturation condition.
Cohesion is the property of the fine grained soil
with particle size below 0.002 mm.
Cohesion of a soil decreases when the moisture
content increases.
14. 14
Cohesionless soil is any free-running type of soil,
such as sand or gravel, whose strength depends
on friction between particles.
5. Moisture Content:
The moisture content (w) is defined as the ratio
of the weight of water in a sample to the weight
of solids. The sample is oven-dried and is
considered as weight of dry soil.
15. 15
6. Soil plasticity& Elasticity :
Soil plasticity is a property that enables the
moist soil to change shape when some force is
applied over it and to retain this shape even
after the removal of the force from it.
The plasticity of soil depends on the cohesion
and adhesion of soil materials.
16. 16
Cohesion refers to the attraction of substances
of like characteristics, such as, that of one water
molecule for another.
Adhesion refers to the attraction of substances
of unlike characteristics.
Soil consistency depends on the texture and
amount of inorganic and organic colloids,
structure and moisture contents of soil.
17. 17
Elasticity :
This elastic behavior is a characteristic of peat.
A soil is said to be elastic when it suffers a
reduction in volume (or is changed shape & bulk)
while the load is applied, but recovers its initial
volume immediately when the load is removed.
18. 18
The most important characteristic of the elastic
behavior of soil is that the soil does not become
permanently deformed.
A. Plastic Limit(PL): The plastic limit (PL) is the
moisture content at which a soil transitions from
being in a semisolid state to a plastic state.
19. 19
B. Liquid Limit (LL) :
The liquid limit (LL) is defined as the moisture
content at which a soil transitions from a plastic
state to a liquid state.
Plasticity Index :
The plasticity index (PI) is defined as the
difference between the liquid limit and the
plastic limit of a soil , PI = LL − PL.
20. 20
The liquid limit, plastic limit, and shrinkage limit
are extremely useful in correlating anticipated
soil behavior with previous experience on soils in
similar consistency states.
Each limit represents a water content at which
the soil changes from one state to another.
21. 21
7. Atterberg Limits :
When a clayey soil is mixed with an excessive
amount of water, it may flow like a semiliquid.
If the soil is gradually dried, it will behave like a
plastic, semisolid, or solid material depending on
its moisture content.
22. 22
The moisture content, in percent, at which the
soil changes from a liquid to a plastic state, is
defined as the liquid limit (LL).
Similarly, the moisture contents, in percent, at
which the soil change from a plastic to a
semisolid state and from a semisolid to a solid
state are define as the plastic limit (PL) and the
shrinkage limit (SL), respectively. These limits are
named as a factor. It is called as Atterberg
limits.
23. 23
The behavior of the soil is therefore related
directly to the amount of water which is present.
In 1911, A. Atterberg defined the boundaries of
four states of consistency in terms of limits.
8. Consistency:
A fine-grained soil can exist in any of several
states of consistency.
24. 24
The particular state of consistency of any
particular soil depends primarily upon the
amount of water present in the soil-water
system.
The behavior of the soil is therefore related
directly to the amount of water which is present.
25. 25
9 . Soil Strength :
The shear strength is the internal resistance per
unit area that the soil can handle before failure
and is expressed as a stress.
The shear strength is the internal resistance per
unit area that the soil can handle before failure
and is expressed as a stress.
26. 26
Strengths are of various kinds.
Uniaxial Compressive Strength (UCS) :
Compressive strength is the capacity of a
material to withstand axially directed
compressive forces.
The most common measure of compressive
strength is the uniaxial compressive strength
(a.k.a. unconfined compressive strength).- apply
Force from top till it creates cracks.
27. 27
Triaxial Compression :
The triaxial compression test involves a soil
specimen subjected to an axial load from all
sides until it attains the state of failure.
10. Compressibility:
When a soil mass is subjected to a compressive
force, its volume decreases.
28. 28
The property of the soil due to which a decrease
in volume occurs under compressive force is
known as the compressibility of soil.
Gravels, sands & silts are incompressible, i.e. if a
moist mass of those materials is subjected to
compression; they suffer no significant volume
change.
29. 29
Clays are compressible, i.e. if a moist mass of
clay is subjected to compression, moisture & air
may be expelled, resulting in a reduction in
volume which is not immediately recovered
when the compression load is withdrawn.
The decrease in volume per unit increase of
pressure is defined as the compressibility of soil,
and a measure of the rate at which consolidation
proceeds is given by the ‘co-efficient of
consolidation’ of the soil.
30. 30
Compressibility of sand & silt varies with density
& compressibility of clay varies directly with
water content & inversely with cohesive
strength.
11. Compaction and Consolidation:
Compaction is a process in which with the help
of mechanical pressing air present in void of soil
is expelled resulting closely packed soil
structure.
31. 31
Compacted soil has better shear strength and
hence better bearing capacity and stability of
soil.
Both terms are very important in
foundation engineering.
Consolidation is any process which involves a
decrease in water content of
saturated soil without replacement of water by
air.
32. 32
All soils undergo elastic compression and
primary and secondary consolidation.
Consolidation and compaction are totally
different process.
Though both process results a reduction in
volume.
33. 33
12. Direct Shear:
The direct shear test is the oldest and simplest
form of shear test.
A soil sample is placed in a metal shear box and
undergoes a horizontal force.
The soil fails by shearing along a plane when the
force is applied.
34. 34
12. Shrinkage and Swell :
Certain soil types (highly plastic) have a large
potential for volumetric change depending on
the moisture content of the soil.
These soils can shrink with decreasing moisture
or swell with increasing moisture.
35. 35
Shrinkage can cause soil to pull away from
structure thus reducing the bearing area or
causing settlement of the structure beyond that
predicted by settlement analysis.
Swelling of the soil can cause an extra load to be
applied to the structure that was not accounted
for in design.
36. 36
Therefore, the potential for shrinkage and
swelling should be determined for soils that
have high plasticity.
Shrinkage and Swell :
Certain soil types (highly plastic) have a large
potential for volumetric change depending on
the moisture content of the soil.
These soils can shrink with decreasing moisture
or swell with increasing moisture.
37. 37
Shrinkage can cause soil to pull away from
structure thus reducing the bearing area or
causing settlement of the structure beyond that
predicted by settlement analysis.
Swell : Swelling of the soil can cause an extra
load to be applied to the structure that was not
accounted for in design.
38. 38
Therefore, the potential for shrinkage and
swelling should be determined for soils that
have high plasticity.
There are certain types of soils that can swell,
particularly clay in the montmorillonite (a very
soft phyllosilicate group of minerals that
typically form in microscopic crystals, forming a
clay) family.
39. 39
Swelling occurs when the moisture is allowed to
increase causing the clay soil to increase in
volume
13. Permeability :
Permeability of a soil is the rate at which water
flows through it under action of hydraulic
gradient.
40. 40
The passage of moisture through the inter-
spaces or pores of the soil is called ‘percolation’.
Soils having porous enough for percolation to
occur are termed ‘pervious’ or ‘permeable’,
while those which do not permit the passage of
water are termed ‘impervious’ or ‘impermeable’.
The rate of flow is directly proportional to the
head of water.
41. 41
Permeability is a property of soil mass and not of
individual particles.
The permeability of cohesive soil is, in general,
very small.
Knowledge of permeability is required not only
for seepage, drainage and ground water
problems but also for the rate of settlement of
structures on saturated soils.
42. 42
Permeability, also known as hydraulic
conductivity, has the same units as velocity and
is generally expressed in ft/min or m/sec.
Coefficient of permeability is dependent on void
ratio, grain-size distribution, pore-size
distribution, roughness of mineral particles, fluid
viscosity, and degree of saturation.
43. 43
14. Electro-Chemical Test :
Electro-chemical tests provide quantitative
information related to the aggressiveness of the
subsurface environment, the surface water
environment, and the potential for deterioration
of foundation materials.
Electro-chemical testing includes pH, resistivity,
sulfate, and chloride contents.
44. 44
15. pH Testing :
pH testing is used to determine the acidity or
alkalinity of the subsurface or surface water
environments.
Acidic or alkaline environments have the
potential for aggressively corroding structures
placed within these environments.
45. 45
16. Resistivity Testing :
Resistivity testing is used to determine the
electric conduction potential of the subsurface
environment.
The ability of soil to conduct electricity can have
a significant impact on the corrosion of steel
piling.
46. 46
If a soil has a high potential for conducting
electricity, then sacrificial anodes may be
required on the structure.
17. Chloride Testing :
Most salts are active participants in the
corrosion process.
Chlorides, sulphates and sulfides have been
identified as being chief agents in promoting
corrosion.
47. 47
Subsurface soils and surface water should be
tested for chloride if the presence of sea or
brackish water is suspected.
18. Durability :
A soundness test determines a granular
materials resistance to disintegration by
weathering and, in particular, freeze-thaw
cycles.
48. 48
Aggregates that are durable (resistant to
weathering) are less likely to degrade in the field
and cause premature failure.
A soundness test involves an initial sieve analysis
to determine the distribution of particle sizes.
19. Angle of Internal Friction: The resistance in
sliding of grain particles of a soil mass depends
upon the angle of internal friction.
49. 49
It is usually considered that the value of the
angle of internal friction is almost independent
of the normal pressure but varies with the
degree of packing of the particles, i.e. with the
density.
The soils subjected to the higher normal stresses
will have lower moisture contents and higher
bulk densities at failure than those subjected to
lower normal stresses and the angle of internal
friction may thus change.
50. 50
The true angle of internal friction of clay is
seldom zero and may be as much as 260
. The
angle of internal friction fro granular soils may
vary in between 280
to 500
.
20. Capillarity :
It is the ability of soil to transmit moisture in all
directions regardless of any gravitational force.
Water rises up through soil pores due to
capillary attraction.
51. 51
The maximum theoretical height of capillary rise
depends upon the pressure which tends to force
the water into the soil, and this force increases
as the size of the soil particles decreases.
The capillary rise in a soil when wet may equal as
much as 4 to 5 times the height of capillary rise
in the same soil when dry.
52. 52
Coarse gravel has no capillary rise;
coarse sand has up to 30 cm;
fine sand and soils have capillary rise up to 1.2 m
but dry sand have very little capillarity.
Clays may have capillary rise up to 0.9 to 1.2 m
but pure clays have very low value.
53. 53
21. Moisture Content & Available water
capacity :
The moisture content (w) is defined as the ratio
of the weight of water in a sample to the weight
of solids. Available water capacity refers to the
quantity of water that the soil is capable of
storing for use by plants.
54. 54
The capacity varies, depending on soil properties
that affect the retention of water and the depth
of the root zone.
The most important properties are the content
of organic matter, soil texture, bulk density, and
soil structure.
Available water capacity is an important factor in
the choice of plants or crops to be grown and in
the design and management of irrigation
systems.
55. 55
Available water capacity is not an estimate of
the quantity of water actually available to plants
at any given time.
22. The consistency limits of the soil are
controlled by the pore fluid pressure.
The fluid in a unconsolidated material promotes
inter-granular cohesion.
Fluid in a soil will promote excess pressure to
cause fluid like behavior of the soil.