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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.).

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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

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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

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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, et al, (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. Sinha, et.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

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

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. Saleh, et.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

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

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,et al, (2004)

 An Introduction to structural health monitoring

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 of SHM that is The process of

applying a damage identification technique for aeronautical, civil and mechanical

engineering infrastructure is called structural health monitoring (SHM). Damage is

defined as changes in the mechanical properties of material and geometric and

structural properties of the systems. It including changes in the boundary conditions

and system inter connectivity or can say inter molecular connectivity between

material molicule which adversely affect the system’s performance. it also concerned

about huge variety of highly accurate local Non-destructive testing mechanisms are

available for such monitoring and also tells about motivation for SHM technology

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development, feature retrieval and information collection, Operational evaluation

and difficulties occurred in SHM.

 Mohammad Osman, et al, (2011)

 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) which can be capable of analyzing the actual behavior of beamcolumn

joints in steel frames in the application of lateral loadings. The software

ANSYS was used to model the joint. They had chosen bolted extended-end-plate

connection as an important type of beam–column joints. The extended-end-plate

connection was chosen for its complexity in the analysis and behavior due to the

number of connection components and their inheritable non-linear behavior. They

chose two experimental tests from the literature to verify their finite element model.

After that they compared the results of both the experimental and the proposed finite

element model were. One of those tests monotonic loading was used, whereas in the

second cyclic loading was used. The finite element model was improved to overcome

the defects of the finite element model which was 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 was used in place of node-to-node element to improve the

model. The FE results showed good correlation with the experimental results. This

was an attempt to improve a new technique for modeling bolts. 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

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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 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 properties of a mechanical structure it also reliable in in-situ analysis because

this method compensate the external noise which are desired in actual condition. In

this study, an experimental set-up of undistorted and distorted beam structures was

exposed to a noisy excitation under turbulent wind conditions. The method of

reforming stochastic equations from measured data has been extended to realistic

noisy excitations like those given here. In our analysis, the part which is to be

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determine had separated from the stochastic dynamics of the system and they

showed 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 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 demerit of this method is that the

noisy excitation of the structure increases the peaks of the frequency spectrum and

so makes it harder to detect and analyze the changes reliability of approach.

 Yasin Kisioglu, et.al, (2013)

 Hydraulic press design under different loading conditions using finite element

analysis

In this study author designed a straight sided four-pillar type hydraulic press and

calculated the stress distribution 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

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

consideration.

 Martin Zahalka, et.al, (2013)

 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

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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

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

deflection, and cost, are aimed 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.ay in here...

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