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In any structure or structural element before application in actual field there is some

testing should have to perform so that to check its reliability and serviceability. So in

characterization process we have to set its limitation either they are structural or

geometrical. At some extent, in beginning of service life of any structure main aim of

SHM is also that to characterize the limiting values only. Latter it defines rest of life

and current performance of structure.

1.2 SHM

The Structural health monitoring can be defined as non-destructive in-situ structural

evaluation method in which several types of sensors and actuators are attached or

embedded in structure. Structural Health Monitoring (SHM) aims to give, at every

moment during the life of a structure, a diagnosis of the “state” of the constituent

materials, of the different parts, and of the full assembly of these parts constituting the

structure as a whole. The state of the structure must remain in the domain specified in

the design, although this can be altered by normal aging due to usage, by the action of

the environment, and by accidental events.

And the rest part is Prognosis in which the prediction of residual life of the structure

is to be done. Due to time-dimension of monitoring, which makes it possible to

consider the full history database of the structure, and with the help of Usage

Monitoring, it can be able to provide a prognosis (evolution of damage, residual life,

etc.).

INTRODUCTION

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In structural health monitoring damage is defined as changes to the material and/or

mechanical properties of a structure, including changes to the boundary conditions,

which adversely affect the structural performance. These sensors collect data which is

analyzed and stored for future analysis and reference that can be used for safety,

integrity, strength or performance.

 Components of SHM

 The structure on which the SHM system will be placed.

 Sensors and Actuators

 Acquisition system

 Communication of information

 Intelligent processing and analyzing of data

 Storage of processed data

 Diagnostics

 Damage modeling and damage detection algorithms

 Retrieval of information as required

INTRODUCTION

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 Layout of structural health monitoring

Fig.1.1 Layout of structural health monitoring

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TABLE 1.1 Categories of SHM

S.no Categories description

1

Static Field Testing

Behavior tests

Diagnostic test

Proof tests

2

Dynamic Field

Testing

Stress history tests

Ambient vibration tests

Dyn. Load Allowance (DLA) tests .

Pullback (anchored cables) tests

3

Continuous

Monitoring

Active monitoring

Passive monitoring

4 Periodic Monitoring

Field testing Tests to determine

changes in structure

 Advantages of SHM

 Increased understanding g of in‐situ structural behavior

 Early damage detection

 Assurances of structural strength and serviceability

 Decreased down time for inspection and repair

 Development of rational maintenance / management strategies

 Increased effectiveness in allocation of scarce resources

 Enables and encourages use of new and innovative materials

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 Levels of SHM

 Level I: This basic level SHM system is capable of detecting damage in a

structure, but cannot provide any information on the nature, location or severity of

the damage .it cannot assess the safety of the structure.

 Level II: Slightly more sophisticated than level 1 SHM system level II system can

detect presence of damage and can also provide information about its location. So

that can be detect and repair

 Level III: In this level we can locate pin point location and of damage and its

severity

 Level IV: It is the most sophisticated system of SHM and provide detailed

information about presence, location and severity of damage and in some extent it

can also provide information about the life of the structure.

1.3 Loading frame

A high stiffness support structure against which the test forces can react. The load

frame comprises a base beam, two columns, and a moving crosshead. It is a selfstraining

structure that means no other load is transfers to ground except its selfweight.

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Fig.1.2 loading frame

 Types of loading frame

 According to axis of loading

o Vertical loading frame

Fig.1.3 Vertical loading frame

INTRODUCTION

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o Horizontal loading frame

Fig.1.4 Horizontal loading frame

 Other types

o Straight Sided four column Type

o Straight Sided box Type

o Straight Sided Column/C-Frame Type,

o H-frame Type,

 Significance of loading frame

 The test-loading frame can be utilized to test the behavior and load-carrying

capacity of both full-size structures as well as separate structural member.

 This equipment is best suited for producing static and repeated loadings

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1.4 Objectives of the study

 Characterization of loading frame

 to monitor health of loading frame.

 vertical stiffness means stiffness of structural member in vertical loadings

 displacements under characteristics load etc

 And comparative study of the general manual results with experimental results.

1.5 Outline of project

 Is to study various aspects of structural health monitoring and part of

instrumentation involved in it.

 Experimental procedure setup and methodology used.

 Description of experimental investigation.

 Description of strain gauges and their types.

 Comparative study of experimental and theoretical results.

1.6 Scope of the work

To achieve the above objective, to the scope of this work for the project generally

involves the following.

 To verify the loading frame geometrically by performing flatness test and

parallelism tests.

 To verify structural performance of frame using strain gauges LVDT’s, data

logger and load cell as instrumentation part and hydraulic jack spacers as

mechanical part.

 To apply the tests more times to verify reliability of our instrumentation system.

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 To make completive study of results of theoretical and experimental calculation

and prediction about health of frame.

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2

Literature survey

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 I.C. Medland , (1966).

 Collapse load of steel frame works allowing for the effect of strain hardening

Concerned an investigation of the behavior of structures composed of the high yieldstress

steel to B.S. 968. Moreover, it concern about the applicability of the plastic

theory to the design of such type of framed structures. In this investigation, he had

conducted a number of bending tests on simply supported beams of having I-sections

in the new steel to check the applicability of the previous theories to the estimation

of the strain-hardening characteristic of such beams. He had found that the rigidplastic-

strain-hardening (r.p.s.h.) and rigid-plastic-rigid (r.p.r.1 theories both gave

good estimates of the strain-hardening characteristic of high tensile steel beams and

that the basic r.p.r. theory could be used as a suitable basis for a design method.

 S.P. Sinhaet.al,(1988)

 Computer aided design of hydraulic press by and

The study was concerned about CAD (computer-aided design) of hydraulic press

structure of capacity 918KN in which they used finite element model to analyze the

press because only through FEM method we can reach near about to model exact

shape like its topology. They also considered factors such as fillet, edge cutting,

provision of openings, change in position of stiffeners and eccentric loading. They

explained us merits of FEM for modeling of such types of complicated structure.

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On the basis of this Investigation, certain significant guidelines related to its

behavior and it’s design have been obtained for the analysis& design in future of

press frames that are.

(i) Clearance between members should be minimum, as much as accuracy expected

from the machine tool;

(ii) Proper alignment of different elements, especially for sliding ones should be

ensured with greater accuracy.

 Dr. Mohamad M. Salehet.al, ( 1992)

 Design study of heavy duty hydraulic machine using FEM technique,

This thesis describes the systematic procedure for investigating the structural

performance and the design and analysis of the welded structure of a 150-tonne

hydraulic press machine in other sense load frame or load carrying structure . This

machine was designed without any measurement earlier. The author has discussed

the theoretical and experimental model of the machine structure to make the

accurate and optimal design analysis for further development in the present machine

design at minimum time and at lower cost. The applicability of the existing

Computer based Finite Element package, as a CAD (computer aided design) tool,

was also discovered. They use both conventional analytical formula and numerical

technique, using Finite Element to model it theoretically. But the conventional

model is based on the simple bending theory in which they use the total strain energy

principle for 2D beams or frames. The LUSAS Finite Element software is used for

numerical modeling because modeling and solving the equation of FEM f such type

of complex structure is too problematic or can say impossible and why they waste

their labor while facilities are. By using FE model they able to be consider such

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factors which are not possible to replicate by other method. The they factors

considered are:- the boundary condition the mesh density and the type of the element

being used. The experimental model consist of load cells strain gages and L.V.D.T.

and A comparison has been made between the experimental and theoretical results.

 L.A. Bisby 2004

 An Introduction to structural health monitoring, L.A. Bisby 2004

Concerned about the introduction to structural health monitoring and its various

aspects like its components, classification, levels, methods of computation etc.also

gives a brief description of sensors and actuators and there types with some example

of bridge structure.

 Charles R. Farrar et.al,(2006)

 An Introduction to structural health monitoring,

The study is concerned about an introductory part about SHM that The process of

implementing a damage identification strategy for aerospace, civil and mechanical

engineering infrastructure is referred to as structural health monitoring (SHM).

damage is defined as changes to the material and/or geometric properties of these

systems, including changes to the boundary conditions and system connectivity,

which adversely affect the system’s performance. it also concerned about wide

variety of highly effective local Non-destructive evaluation tools are available for

such monitoring and also tells about motivation for SHM technology development,

feature extraction and information condensation, Operational evaluation and

Challenges for SHM.

 Mohammad Osman et al (2011)

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 Finite element analysis of beam-column joints in steel frames under cyclic

loading.

This study is concerned to develop simple and accurate three-dimensional (3D) finite

element model (FE) capable of predicting the actual behavior of beam-to-column

joints in steel frames subjected to lateral loads. The software package ANSYS is used

to model the joint. The bolted extended-end-plate connection was chosen as an

important type of beam–column joints. The extended-end-plate connection is chosen

for its complexity in the analysis and behavior due to the number of connection

components and their inheritable non-linear behavior. Two experimental tests in the

literature were chosen to verify the finite element model. The results of both the

experimental and the proposed finite element were compared. One of these tests was

monotonically loaded, whereas the second was cyclically loaded. The finite element

model is improved to enhance the defects of the finite element model used. These

defects are; the long time need for the analysis and the inability of the contact element

type to follow the behavior of moment–rotation curve under cyclic loading. As a

contact element, the surface-to-surface element is used instead of node-to-node

element to enhance the model. The FE results show good correlation with the

experimental one. An attempt to improve a new technique for modeling bolts is

conducted. And Concluded that FE results and the experimental results are compared

to examine the validity and the predictability of the proposed model. The FE results

have good agreement with the experimental one at different stages of loading. The FE

model can provide a variety of results at any location within the model. A viewing of

the full fields of stresses and strains are possible in the FE model. This provides a

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great advantage in monitoring the components of the connection. And shown that

modeling a beam-to-column connection loaded cyclically is expensive and time

consuming in both building and solving the model. So, there is a great need to model

the connection more simply and at the same time with an acceptable accuracy. and

gave a proposal for a new technique of modeling bolts is presented. The proposal is to

model the bolts as a mixing of shell elements (for head and nut) and link elements

(for shank). This technique for modeling of bolts, called shell bolt, was examined and

compared to other methods for modeling of bolts and was found to be accurate. Also,

it needs less time of solution and less storage volume comparing with other

techniques for modeling the bolts.

 Philip Rinn et al (2012)

 Stochastic method for in situ damage analysis,

study is concerned about physics of stochastic processes we present a new approach

for structural health monitoring. this new method allows for an in-situ analysis of

the elastic features of a mechanical structure even for realistic excitations with

correlated noise as it appears in real world situations. In particular an experimental

set-up of undamaged and damaged beam structures was exposed to a noisy

excitation under turbulent wind conditions. The method of reconstructing stochastic

equations from measured data has been extended to realistic noisy excitations like

those given here. In our analysis the deterministic part is separated from the

stochastic dynamics of the system and we show that the slope of the deterministic

part, which is linked to mechanical features of the material, changes sensitively with

increasing damage. The results are more significant than corresponding changes in

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eigen frequencies, as commonly used for structural health monitoring. Commonly

detection systems use fast Fourier transformation (FFT) to extract system features

and to determine the condition of the system from changes in the eigen frequencies.

One drawback of this approach is that noisy excitation of the structure broadens the

peaks of the frequency spectrum and thus makes it harder to detect changes reliably.

 Yasin Kisioglu et.al,(2013)

 Hydraulic press design under different loading conditions using finite

element analysis

this study, a suitable hydraulic press having four-column is designed and the stress

distribution is calculated using both analytical and finite element methods under

different loading conditions. Three different loading types, axial, eccentric and

oblique, are considered in design process. Six different types of standard sections

having the same cross-sectional area are used for the press columns. Three different

models for the press head are designed to hold the hydraulic cylinder. Therefore,

eighteen different design combinations for a hydraulic press are modeled under three

different loading conditions. Their stress distributions are calculated using a

computer-aided finite element analysis (FEA) tool and analytical formulas and the

obtained results are compared. Two different types of finite elements, shell and beam,

are used for the modeling processes. Based on the obtained results, the best model for

the hydraulic press considering the head and body types is defined. and recommended

that T type head and hollow circular or I-sectioned column is the best design

consideration.

 Martin Zahalka et.al, (2013)

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 Modal analysis of hydraulic press frames for open die forging,

the study discuss the dynamic behavior of the forging machines is necessary to

explore due to the increasing of speeds on large forging hydraulic presses for open die

forging. The study describes the modal analysis of two selected presses, which

represent the most common designs of hydraulic presses for forging. The first press is

with double-column frame CKV 50 with the force 50MN and the second one is with

four-column frame CKV 170 with the force 170 MN. Further are described the

simulations of oscillation, which was excited by time-dependent work force. Results

of analysis are compared with measurement in the real operation. w and concluded

that we can get higher second moment of area with the same area of cross section by

changing of shape only.

 Santosh kumar et al (2014)

 Analysis and structural optimization of 5 ton H-frame hydraulic press,

In above st Discussed about Using the optimum resources possible in designing the

hydraulic presses frame can effect reduction in the cost of the hydraulic presses. By

optimizing the weight of material utilized for building the structure. An attempt has

been made in this direction to reduce the volume of material. So here we consider an

industrial application project consisting of mass minimization of H-frame type

hydraulic press. This press has to compensate the forces acting on the working plates

and has to fulfill certain critical constraints. ANSYS has been used for this analysis

the main aim is to reduce the cost of the Hydraulic presses without compromising on

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the quality of the output. With regarding to design specification, stress distribution,

deflection, and cost, are focused on optimized design. The methodology followed in

this work is comparison of stresses induced in machine for different thickness used

for construction of frame and column of the H-frame type hydraulic press. In this

project it has been compared original design of H frame type hydraulic press with

design that have been optimized by using software tool (ANSYS) .

2.2 Critique

Since lot of work has been done on SHM of steel frame for both static condition the

type of testing methods from analog to digital .

Further work has been done on structural analysis and optimization of loading frame

and hydraulic presses we plant to replicate that for our loading frame.

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3

Experimental SETUP

--------------------------------------------------------------

3.1 Instrumentations setup

Because there are so many difficulties in analogue signals about collection and

retrieval of result data. So we are performing such the experiment which gives us

results in digital form. Which needs an electronic data acquisition system which also

enable to store the data which can be retrieved when required that’s why we have to

involve some electronics Instruments and circuits which are as follows

 Multi-channel Digital Automatic Data Loggers for Strain measurement.

 Strain Gauges

 Wheat stone bridge

 Load Cells & Digital Load Indicators

 Displacement Transducers

3.2 Multi-channel Data Loggers

It’s a major part of data acquisition system as name define its work itself it logs the

data in it in its own units or we can also define them. In some cases it also works as an

actuator which means it gives excitation or input to the sensors but which haven’t

such excitation system in that cases we have to involve external excitation system or

external controlled supply like some battery or other one. In our case we are using a

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sixteen channel data logger names DT-85 no. of channels define that how many

sensors we can attach and read the values. So in our case we can read 16 sensors at

one time instant. There is also such type of arrangement is available by which we can

expand the no of channels with the help of channel expansion module up to 10

channels. It is also preferred as an actuator for some small range of excitation from

300 mille volt to 3 volt. In this case it receives the signals in certain fix time interval

vary from 1 second to 30 seconds. We can also set it in a triggering system by which

we can control the frequency of data collection with the help of a small button. Its

having some memory in which it can store data up to a certain limit we can retrieve in

the system in excel sheet or we can also retrieve it in some other storage device with

the help of USB port. Data loggers are available in different frequency range small

frequency data loggers are static loading cases.

Fig.3.1 Data logger

For experiment dynamic loading high frequency data loggers are required. Our data

logger is of small frequency range so we using it for our case.

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3.3 Strain Gauges

Again name suggesting instruments or can say transducer used for strain

measurements is called strain Gauges over a free surface of any structure. They follow

different principals according to their types. That means there are different types of

strain gauge are available according there range least count type of measurement and

scope which are as follows.

 Mechanical strain gauges

 Acoustical strain gauges

 Optical strain gauges

 Pneumatic strain gauges

 Electrical strain gauge

 Mechanical strain gauges

These are involves with mechanical arrangements in its working principal consist of

two jaws clamped with the surface or structural on which strain is desired by means of

spring or some clamping arrangements at certain specific distance which is called

gauge length. So when specimen or component was loaded it get elongated so the jaw

clamped with component is also get displaced from its original position. And this

displacement is amplified and by some mechanical arrangement and visualized on the

proving ring or some dial meter. Due to its working principal in some extent, it can

also be called extensometer. These are also having so many types are as follows.

 Berry’s strain gauge

 Huggenbeger extensometer

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 Johnsson extensometer

Fig.3.2 Berry’s strain gauge

 Acoustical Strain Gauge

Its working principal is based on the propagation or traveling of wave. Which mean

when bonded wire is stressed or elongated its natural frequency get altered or differs

from its original values so we have to amplify this change in terms strain developed.

These types of gauges are highly accurate in nature.

 Optical strain gauges

As the name suggests it is based on the principal of optics. In this type of gauge the

pivot jaw containing a mirror and the other jaw o edge is clamped with surface of

component on which strain is desired. So when the component is stressed or elongated

the pivoted edge which is carrying mirror got tilt and that ‘s why mirror will also got

tilt and the reflection of the illuminated scale is visible on this mirror which can be

read with the help of telescope. There are two types of optical strain gauge s are

known named as follows.

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 Marten’s optical strain gauge

 Tuckerman optical strain gauge

Fig.3.3 Marten’s optical strain gauge

 Pneumatic strain gauges

The working principal of these type of gauges are based on relative study of discharge

of air between two orifice in which one is fixed and other is variable. Sensitivity of

these type gauges are 100000 times of other types. And can be used for both static and

dynamic condition.

Fig.3.4 Pneumatic strain gauges

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 Electrical strain gauge

It also having three types but hear we are using resistance so we will explain about

resistance type only. Others name are as follows.

 Inductance type

 Capacitance type

 Resistance type

These strain gauges works on the principal that they amplify the mechanical

deformation or change of structural component in electrical output. It may be of any

type in impedance or resistance. It consists of a conductor circuit in its structure

attached with component. So when conductor is starched or compressed it results

change in resistance of conductor because cross sectional area of conductor got

change either increased or decreased. Change in resistance per unit strain is known as

gauge factor which indicates about the sensitivity of strain gauge. There different

types of strain gauges are available are as follows.

 Un-bonded wire strain gauge

 Bonded wire strain gauge

 Foil strain gauge

 Weldable strain gauge

 Un-bonded wire strain gauge

This type of strain gauge gives electrical signal output of relative displacement of

one body to another body. It consists of a stationary frame and a movable platform

and pins made of insulated material are in those pins loops of wire are wounded

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which are in pretension. So when component is elongated or contracted the relative

movement between frame and platform will occurs and tension in loops get alters

after that this is connected with for arm wheat stone bridge for the accuracy purpose.

These type of strain gauges are also used for the measurement of force pressure

acceleration etc.

Fig.3.5 Un-bonded wire strain gauge

 Bonded wire strain gauge

it consists of wire bonded around a core which is sandwiched between two insulating

layers. Sometimes core is flattened this then this is called Flat-grid strain gauge type

is also sub divided into three another types.

 Wrap-around wire strain gauge

 Flat-grid strain gauge

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Fig.3.6 Bonded wire strain gauge

 Weldable strain gauge

They are mainly invented due to ease in installation working principal is same as

that of other resistance based strain gauges. There installation is easy. And they can

work in any environment. It consists of strain sensitive material and stain component

is highly insulated by compacted ceramic. Stain gauge is spot weld on structural

component and when structure is stressed the stress get transmitted through weld into

strain tube. These types of strain gauges also have dynamic application.

Fig.3.7 Weldable strain gauge

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 Foil strain gauge

This type of strain gauge consisting of a membrane of larger width as compare to its

thickness and it is made up of strain sensitive material and principal is same means

when structural component is strained foil also experiences strain and its resistance

get changed. A suitable cementing material should also be required for bonding of

strain gauge with structural component.

The strain gauge which we are using is of foil type having following specification

Resistance - 120 ohm and 350 ohm lead attached.

We have also used wheat stone bridge system for better accuracy purpose.

Fig.3.8 Foil type strain gauge

3.4 Wheat stone bridge

It’s an arrangement of resistances used for achieving greater accuracy in

measurement. It consists of two resistances connected in series an again they

connected parallel with another two resistance of same resistance value.

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Fig.3.9 Wheat stone bridge

3.5 Load Cells & Digital Load Indicators

As the name suggests it is an electromechanical device or equipment used to read the

value of load is called load cell gives the value of load in digital format. It can be say

that it’s a transducer as it converts mechanical forces into the form of electrical energy

or signals .Its basic principal of working is based on the strain gauges. The internal

structure or sensing system of load cell consists of a Wheatstone full bridge system of

strain gauges. So when load is applied then the strain in strain gauges will increases

linearly because of another principal hook’s law and because of that resistance will

also increasing linearly with the deformation. There are so many different types of

load cells are available according to different criteria’s as follows.

 According to construction material

 Aluminum load cell

 Tool steel load cell

 Stainless steel load cell

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 According to external structure and working

 Canister type

 Single ended beam type

 Double ended beam type

 Cantilever beam type

 S-beam type

 Platform type

Hear we used a canister type of load cell having capacity of 50 ton or 500 KN shown

bellow.

Fig.3.10 Load cell

3.6 Displacement Transducers (LVDT)

Displacement transducer name LVDT expands and form linear variable differential

transducer. Its function is to convert linear displacement caused by any mechanical

mean into an electrical signal in output containing magnitude and direction. Its

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internal structure consists of transformer means its having two coil named primary

and secondary. Primary coil wounded at mid over a hollow cylindrical and nonconductive

generally made up of glass polymer. And secondary windings are

wounded on top and bottom on hollow tube means on both sides of primary one. A

core made up of ferromagnetic material and a its length should be a fraction of length

of whole assembly containing insulator tube primary winding and secondary winding.

So that when core energized primary one and move towards bottom coil flux changes

and voltage, will decreases so voltage difference increases and readings are shows on

display. Our LVDT’s maximum range to measure displacement is 40mm that is

20mm in positive side and another 20mm are on negative side. An image of LVDT

and its indicator display is shown bellow.

Fig.3.11LVDT

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Fig.3.12 DIGITAL DISPLAY of LVDT

We also require some more instruments that are not have any electronic phase Name

as.

 Loading frame

 Hydraulic Jack

 Other accessories

3.7 Loading frame

We have given its brief introduction earlier. And our loading frame having following

specifications.

 Firstly sectional properties of beam-

 Depth of the section h = 600 mm

 Width of the flange bf = 210 mm

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 Thickness of the flange tf = 20.8 mm

 Thickness of the web tw = 12 mm

 Radius at root r1 =20 mm

 Depth of web d = h- 2(tf + r1) = 518.4 mm

 Section Modulus Ze= 3060.4 x 103 mm3

 Plastic Modulus Zp = 3510.63 x 103 mm3

 . Weight per Meter W = 1202.71 N/m

 Capacity of frame=500 KN

 Specifications of stiffeners

 ISLC 75 section

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Fig.3.13 Loading frame

3.8 Hydraulic Jack

We can apply large mechanical loads with help of a suitable hydraulic arrangement in

a setup. Consists of a pressure gauge with analog dial, piston, cylinder, oil filling and

exit arrangement and a lever by which we can apply pumping force and it also have a

release valve to remove or to release pressure.

The hydraulic jack we used having maximum capacity to apply load of 50 ton or 500

KN its least count is 2 KN and it also have locking arrangement for lever pump.

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Fig.3.14 Hydraulic Jack

3.9 Other accessories

It consists of accessories like adhesive, spacers shielded wires, special cello tape for

strain gauges, stands for LVDT, Teflon sheet, soldering iron, machine and wire, flux

etc.

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4

Experimental studies

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Like in any characterization, we have to find the upper and lower limitation about that

instrument or whatever is characterized. And that will also help in finding that how

much it is reliable. So to know about structural performance or can say structural

health monitoring is a part of characterization of our loading frame. But in

characterization this not only test which we will have to perform there is some more

like flatness test of top and bottom surface both and parallelism test etc because

currently we would not have any standards specifically for such types of loading

frame but we have some codel provision for testing machine in which we can apply

static mechanical loads on test specimen. That are provisions for hydraulic press

given in IS codes because in our loading frame we used hydraulic jack arrangement

for loading purpose and we had applied static load and also we designed it for testing

of structural modal and components so we can characterize it as a two column straight

sided hydraulic press as per define by bureau of Indian standard in IS codes defined

for hydraulic presses.

4.1 Testing of geometrical parameters

First of all we will check is geometrical parameters assuming code IS-14877 Part1 as

standard. Tests given bellow.

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 Flatness of top Surface

In the test we mount, dial gauge on a magnetic base which is again attached with a

standardized zero roughness too smooth base plate and slide towards another column

to left one and noted the major readings on dial gauge.

 Flatness of bottom Surface

We have done or can say repeated same experiment as stated earlier in above

paragraph with bottom surface to check the same and noted down major undulations

on dial gauge.

 Parallelism

It is the test to measure the relative undulation between the surfaces of frame with

respect to each other. For this we have to fix dial gauge in a smooth base stand and

slide it towards another column from one. We can left 25mm distance from both

column as given in Indian code. Means that areas are free to uneven because of joints.

Fig.4.1 parallelism testing

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4.2 Structural Performance investigation

Structural performance of any structure consists of several things like it’s rigidity

against various loads like in bending shear torsion etc. in our case to find rigidity of

structure experimentally we can perform strain analysis using strain gauges and

LVDT’s. for this we have to mount strain gauges at further places where stress are

supposed to be critical. Since it is a self-straining structure, so it was assumed that no

load or moment is supposed to be transfers to ground or foundation. So all strain

gauges are laced at mid span and extreme outer fiber.

 Location of strain measurements

Fig.4.2 Location of strain gauges

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