- Steel exhibits ductile behavior by allowing large strains before rupturing or failing. It can stretch substantially under tension.
- Concrete and cast iron exhibit brittle behavior, failing abruptly with little warning once their strength limits are exceeded. Their stress-strain curves are steep with little plastic deformation.
- Reinforced concrete can show ductile behavior if designed properly with sufficient confinement and ductile reinforcement to allow inelastic deformations without collapse.
Geotechnical Engineering-II [Lec #6: Stress Distribution in Soil]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.
Geotechnical Engineering-II [Lec #6: Stress Distribution in Soil]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.
Structural engineering i- Dr. Iftekhar Anam
Structural Stability and Determinacy,Axial Force, Shear Force and Bending Moment Diagram of Frames,Axial Force, Shear Force and Bending Moment Diagram of Multi-Storied Frames,Influence Lines of Beams using Müller-Breslau’s Principle,Influence Lines of Plate Girders and Trusses,Maximum ‘Support Reaction’ due to Wheel Loads,Maximum ‘Shear Force’ due to Wheel Loads,Calculation of Wind Load,Seismic Vibration and Structural Response
http://www.uap-bd.edu/ce/anam/
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.
The aim of this manual is to give the design application of the basic requirements of EC8 for new concrete and steel buildings using ETABS. This book can be used by users of ETABS modeler. Is not cover all the steps that you have to carry during designing model using ETABS but is a good manual for those who using Eurocodes.
Structural engineering i- Dr. Iftekhar Anam
Structural Stability and Determinacy,Axial Force, Shear Force and Bending Moment Diagram of Frames,Axial Force, Shear Force and Bending Moment Diagram of Multi-Storied Frames,Influence Lines of Beams using Müller-Breslau’s Principle,Influence Lines of Plate Girders and Trusses,Maximum ‘Support Reaction’ due to Wheel Loads,Maximum ‘Shear Force’ due to Wheel Loads,Calculation of Wind Load,Seismic Vibration and Structural Response
http://www.uap-bd.edu/ce/anam/
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.
The aim of this manual is to give the design application of the basic requirements of EC8 for new concrete and steel buildings using ETABS. This book can be used by users of ETABS modeler. Is not cover all the steps that you have to carry during designing model using ETABS but is a good manual for those who using Eurocodes.
Plasticity, Theory of Plasticity ,Creep in concrete ,Creep, Stiffness ,Elasticity ,Plasticity ,Euler-Bernoulli beam equation, Buckling, Ductility VS Malleability, Ductile Materials, Brittle Materials ,Modulus of Elasticity, Plastic Strain, Tensile Strength, Yield Strength, Ultimate Strength, Solid mechanics or Mechanics of solids, Strength of Materials, Types of forces, Normal forces, Fatigue , Resilience, Unit of Resilience, Modulus of rigidity , Modulus of Resilience, Modulus of Toughness Poisson’s Ratio.
The section will cover the behaviour of materials by introducing the stress-strain curve. The concepts of elastic and plastic deformation will be covered. This will then lead to a discussion of the micro-structure of materials and a physical explanation of what is happening to a polycrystalline material as it is loaded to failure.
Analysis of failure behavior of shear connection in push-out specimen by thre...IJERDJOURNAL
ABSTRACT:- This study analyzes the failure mechanism of shear connection by three-dimensional finite element analysis (FEA) of push-out specimens that was practically unaffordable experimentally or by twodimensional FEA. For the analysis of the failure behavior of the compression strut formed in the loaded concrete member, the three-dimensional principal stress space is transformed into two-dimensional space by means of the relation between the hydrostatic stress and the deviatoric stress. The analysis of the stress state in the compression strut revealed that the deviatoric stress increases with larger load particularly in the concrete surrounding the lower part of the shear stud. Accordingly, bearing failure of concrete occurred locally within a limited region in the slab. The steep increase of the deviatoric stress accompanying the increase of the load resulted in the failure of concrete around the lower part of the shear stud, which in turn provoked the deformation and the development of bending moment of the shear stud. Finally, plastic hinge formed in the shear stud leading it to reach its limit state. The proposed finite element model can also be used to model the shear connection of the composite beam and, the proposed stress analysis method can be applied to analyze its composite action behavior.
CROSS-CORRELATION OF STRESSES IN THE TRAN REINFORCEMENT UNDER SHEAR LOAD AND ...IAEME Publication
The main aim of the present study is to give an answer to the question whether the transverse reinforcement, which is required for the shear resistance of columns, must be added to the one required for the cross section confinement, or it is possible for one to substitute the other. The superposition of these reinforcements is defended by the fact that the shear reinforcement results from the shear action, while the transverse reinforcement, required by the confinement, results from the axial compression of the section. The present study is experimental and uses strain gauges, in order to check the stresses of the transverse reinforcement. Useful conclusions are drawn.
Structural Integrity Analysis: Chapter 3 Mechanical Properties of MaterialsIgor Kokcharov
Structural Integrity Analysis features a collection of selected topics on structural design, safety, reliability, redundancy, strength, material science, mechanical properties of materials, composite materials, welds, finite element analysis, stress concentration, failure mechanisms and criteria. The engineering approaches focus on understanding and concept visualization rather than theoretical reasoning. The structural engineering profession plays a key role in the assurance of safety of technical systems such as metallic structures, buildings, machines, and transport. The third chapter explains the engineering tests and fundamentals of mechanical properties of materials.
System shear connector digunakan sebagai aplikasi dalam konstruksi bangunan untuk menghasilkan kekuatan coran beton lebih kuat dan stabil sesuai dengan perhitungan engineering civil. Dalam hal ini ada 2 hal perhitungan kekuatan secara umum yaitu kekuatan kelengketan stud pada batang baja sesudah dilas. Dan yang kedua adalah kekuatan stud bolt yang digunakan.
Evaluation of the Seismic Response Parameters for Infilled Reinforced Concret...IOSRJMCE
RC frames with unreinforced masonry infill walls are a common form of construction all around the world. Often, engineers do not consider masonry infill walls in the design process because the final distribution of these elements may be unknown to them, or because masonry walls are regarded as non-structural elements. Separation between masonry walls and frames is often not provided and, as a consequence, walls and frames interact during strong ground motion. This leads to structural response deviating radically from what is expected in the design. The presence of masonry infills can result in higher stiffness and strength and it is cheap and built with low cost labor. Under lateral load, Masonry walls act as diagonal struts subjected to compression, while reinforced concrete confining members (Frames) act in tension and/or compression, depending on the direction of lateral earthquake forces. The main objective of this research is to develop a realistic matrix for the response modification factors for medium-rise skeletal buildings with masonry infills. In this study, the contribution of the masonry infill walls to the lateral behavior of reinforced concrete buildings was investigated. For this purpose, a five, seven and ten stories buildings are modelled as bare and infilled frames. The parameters investigated were infill ratio, panel aspect ratio, unidirectional eccentricity, bidirectional eccentricities. A Parametric study was developed on the behavior of medium rise infilled frame buildings under lateral loads to investigate the effect of these parameters as well as infill properties on this behavior
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
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
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.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
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.
1. GAZIANTEP UNIVERSITY
GRADUATE SCHOOL NATURAL AND APPLIED SCEINCE
DEPARTMENT OF CIVIL ENGINEERING
M.SC IN CONSTRUCTION ENGINEERING
COURSE CODE: CE545
DEFORMATION AND FRACTURE THEORIES
STUDY No: 3
Brittle Ductile Behaviour For ( STEEL - RIENFORCED CONCRETE - CONCRETE )
Submitted by
AHMED ASSIM ABDULLAH
STD No: 201444960
2. Brittle: The ability of a material to show little or no yielding before
failure.
Ductile: The ability of a material to be subjected to large strains before it
ruptures or fails.
Concrete: The ability of a material to show little or no yielding before
failure.
Reinforced concrete: A concrete member with steel embedded inside it
to resist tensile forces.
Steel: Refined iron that contains virtually no impurities.
Typical Material Properties and Engineering Terms
Structural engineers use material properties when designing
members. Stress (σ) is the applied load divided by the material area
it is acting on (typically the cross-sectional area of the member).
Strain (ε) is the elongation or contraction of a material per unit
length of the material. According to Hooke's Law (σ = Eε) stress is
dependent on strain in the material. The modulus of elasticity (E) or
Young's modulus of a material is a constant associated with Hooke's
Law. The modulus of elasticity indicates the stiffness of a material.
Tensile strength is the amount of tensile stress that a material can
resist before failing. Compressive strength is the amount of
compressive stress that a material can resist before failing. A
material that exhibits ductile properties can be subjected
to large strains before it ruptures or fails. A material that exhibits
brittle properties shows little or no yielding before failure.
3. 1. Failure of Concrete
It has been proposed elsewhere that a realistic lower bound for the
above peak level appears to be the level at which the volume of a
specimen attains a minimum value. This minimum volume level has
been found to lie very close to the maximum stress level that can be
sustained by a concrete specimen and considered to provide a failure
criterion suitable for practical structural analysis Although for a given
concrete the variation of the above level in stress space has been
found to be slightly stress path dependent the unsystematic
variability of the results obtained from the tests on various concretes
is such that it renders the above dependency insignificant for any
pratical purpose (figure 1).
Fig 1 : A, Unsystematic variability of "failure" data obtained from
tests using stress path 1 for concretes with f~(N/mm 2) varying
between approximately 15 and 65. B, Stress path effect on "failure"
data for a typical concrete (f~= 31.7 N/mm2).
4. Deformational behaviour during loading
he trends of behaviour exhibited by concrete under stress increasing
to failure have been established in previous investigations by
analysing experimental data on the multiaxial behaviour of a wide
range of concretes likely to be used in practice with uniaxial cylinder
compressive strength (fc) varying between approximately 15 N/mm z
and 65 N/mm 2 . The most realistic representation of these
experimental data is achieved by decomposing each state of stress
and strain into hydrostatic and deviatoric components in the form of
normal and shear octahedral stresses and strains, respectively. In this
form of representation, the deformational behaviour of concrete
under increasing stress (behaviour under decreasing stress is
discussed later) can be completely described by the relationships
between (a) hydrostatic stress, Co, and volumetric strain, %h, (b)
deviatoric stress, Xo, and deviatoric strain, %, and (c) deviatoric
stress. Typical relationships are shown in figures 2 and 3 for a
cc.~crete with 20 mm maximum size of gravel aggregate and f~= 31.7
N/ram 2.
Fig 3 : Hydrostatic component of deformationai
response of typical concrete under deviatoric stress.
Fig2 : Deformational response of a typical concrete under (a)
hydrostatic and (b) deviatoric stress
5. The CrO-eo~relationship defines completely the deformational
response of concrete under increasing hydrostatic stress, since the
measured deviatoric strain under such a state of stress has been
found to be negligible Furthermore, it has been found that
specimens subjected to various levels of uniaxial compression below
the failure level, when unloaded and then reloaded hydrostatically,
exhibit a stress-strain relationship essentially the same as that
exhibited under increasing hydrostatic stress by specimens without
any previous loading history In view of this experimental evidence, it
appears realistic to consider that the volumetric strain (%h) of
concrete due to the hydrostatic component (Co) of the applied state
of stress is independent of the deviatoric component (Xo), and thus
%h may be expressed irr terms of r o only. The deformational
response of concrete under increasing deviatoric stress (%) is defined
by both Xo- Yo and % - %d relationships which have been found to be
essentially independent of the direction of zo on deviatoric planes,
i.e. planes orthogonal to the stress space diagonal at given levels of
cro As for ero--%h relationship, the To - % relationship has been
found to be essentially unique, i. e. for a given concrete, 70 is
dependent on % only On the other hand, the zo-%d relationship is
dependent on (ro and appears to represent the only form of
interaction (coupling) between the hydrostatic and deviatoric
components of the stress and strain states .
Defornmtional behaviour during unloading
An indication of the stress-strain behaviour of concrete during
unloading may be given by uniaxial and triaxial experimental data
obtained from cyclic tests. The hysteresis loop exhibited by such data
during the first cycle is so small that the same linear stress-strain
relationship may realistically describe concrete behaviour during
both unloading and subsequent reloading up to the maximum stress
6. level previously experienced by the material Figure 4 indicates that
this linear relationship has an essentially constant inclination and its
distance from the origin of the monotonically increasing stress-strain
curve increases with the maximum stress level of the cyclic load. For
stress levels beyond this maximum stress, concrete response is
described by the monotonically increasing stress-strain relationships
discussed in the preceding section.
Fig 4 : Measured and predicted stress-strain behaviour during
loading and unloading/reloading for a typical concrete under ( a )
uniaxiai and (b) t r i a x i a l compression.
7. Causes Of Observed Behaviour
It is generally accepted that the short-term nonlinear behaviour of
concrete under increasing stress is dictated by internal processes
which take the form of extension and propagation of cracks, some of
which exist within the material even before the application of load
Crack extension and propagation occurs in localised regions in order
to relieve high tensile stress concentrations which develop near the
crack tips .This process results in formation of voids which
tend to increase the volume of concrete. However, the reduction of
high tensile stress concentrations may be considered equivalent to
the application of an internal compressive state of stress which tends
to decrease the volume of the material . The effect of void formation
on deformation, although detectable is small and may be ignored .As
a result, the internal compressive state of stress is considered to be
the predominant cause of the observed nonlinear response of
concrete under increasing stress. During unloading, the fracture
processes cease and, as discussed in the preceding section, concrete
behaviour is essentially linear. Fracture resumes when the maximum
stress level previously experienced by the material is exceeded.
Failure criterion
Unsystematic variability of "maximum stress" level
exhi'bited by concretes with f~ (N/ram 2)
varying between approximan of fadure" revel trom max
tely 15 and 65. B, Deviatio stress"
level for a typical concrete (f~=47 N/ram2).
8. 2. Ductility and fracture of Reinforced Concrete Structural
The basic reason most buildings do not collapse under seismic action
is a material property called ductility. It is the property of a material
to deform permanently without loosing its strength, i.e. without
decreasing its ability to resist during deformation. A piece of wire,
e.g. an office clip bends but not brake. Due to ductility a system
“resists” mobilizing all its reserves (Fig. 2.1).
Figure 2.1 Ductility of a steel beam under bending
Ductility of metals occurs due to the relocation of zones of molecules
while they are still bonded with tensile forces. This behaviour occurs
under tensile and compressive stress. Concrete exhibits satisfactory
ductility in compression caused only by the slide mechanism (friction)
when it is simultaneously laterally under compression. When concrete is
not laterally compressed it exhibits reduced ductility since the
fracture mechanism is functioning that quickly exhausts the limits of its
further deformation (Fig. 2.2). The behaviour of concrete in tension and
in shear is not ductile but brittle.
Figure 2.2 Conventional concrete under compression without (1) or with confinement (2)
9. Reinforced concrete exhibits ductile behaviour when:
- its longitudinal reinforcement is low (under-reinforced).
- it is over-reinforced transversely (stirrups).
- it sustains limited compressive stress.
- it contains everywhere the minimum constructional reinforcement
to be protected against tensile / shear brittle failure.
- it is confined and has compressive reinforcement in highly
compressed zones and in plastic hinges regions.
- it is appropriately designed as a system, i.e. does not receive major
concentrated deformations in particular positions (ground floor
pilotis, short columns).
- reinforcements are sufficiently anchored to prevent loss of
concrete cover or spalling at these positions. Finally it should be
emphasized that current understanding of earthquake resistant
design of structures is the assurance of the ductile behaviour of the
system through the definition of appropriate positions where
inelastic deformations will occur. This method is called capacity
design and comprises the basis of many modern earthquake
resistant design Codes (e.g. EC 8, EAK 2003).
Notes about ductility and fracture of reinforced concrete
Other materials e.g. fiber-reinforced mortars, high-strength concretes exhibit
ductility under compression and under tension due to the slip (friction) of
fibers within the mortar’s matrix.
10. 3. Ductile , Brittle Behavior in Steel
Before fracture mechanics - impact testing was used to measure
impact behaviour and likelihood of brittle fracture. Developed in
response to onset of brittle failure in ductile materials e.g. steel
ships, bridges etc.
- Still used in quality control and Standards (ship plate etc).
Primary function of Charpy test
at high temperature, CVN for steel is relatively high but drops
with decrease in temperature.
at low temperature steel can be brittle.
the sudden drop in impact energy is the ductile-to-brittle
transition (DBT).
steels should always be used above their DBT .
ceramics and polymers also experience DBT .
The stress-strain curve for different material is different. The figure
below shows the comparison of the curves for mild steel, cast iron
and concrete. It can be seen that the concrete curve is almost a
straight line. There is an abrupt end to the curve. This, and the fact
that it is a very steep line, indicate that it is a brittle material. The
11. curve for cast iron has a slight curve to it. It is also a brittle material.
Both of these materials will fail with little warning once their limits
are surpassed. Notice that the curve for mild steel seems to have a
long gently curving "tail". This indicates a behavior that is distinctly
different than either concrete or cast iron. The graph shows that
after a certain point mild steel will continue to strain (in the case of
tension, to stretch) as the stress (the loading) remains more or less
constant. The steel will actually stretch like taffy. This is a material
property which indicates a high ductility.
If the original cross-sectional area is used to calculate the stress for
every value of applied force, then the resulting diagram is known as
the Engineering Stress-Strain Diagram. However, if the applied force
is divided by the actual value of the cross-sectional area, then the
resulting diagram is known as the True Stress-Strain Diagram.
Therefore, in engineering stress-strain diagram the ultimate and
failure strength points do not coincide whereas in the true diagram
they do. The difference in the two diagrams becomes apparent in the
inelastic region of the curve where the change in the cross-sectional
area of the specimen becomes very significant.