Title of Invention	APPARATUS FOR TESTING A STRUCTURAL SPECIMEN SUBJECTED TO BENDING AND TORSION.
Abstract	Apparatus for testing structural specimens (made up of steel, concrete or composite material subject to bending, torsion and combined bending and torsion) comprising of portal load frame, actuator, grips and fixtures for RSJ specimen, resistance strain gages, ball bearing with lever arrangement, means to study the stress and strains produced in the material and arrangement to plot the frequency Vs displacement curves. The apparatus is used to study the bending and torsional effects produced in the structural specimens under different loading conditions.

Title of Invention

APPARATUS FOR TESTING A STRUCTURAL SPECIMEN SUBJECTED TO BENDING AND TORSION.

Abstract

Apparatus for testing structural specimens (made up of steel, concrete or composite material subject to bending, torsion and combined bending and torsion) comprising of portal load frame, actuator, grips and fixtures for RSJ specimen, resistance strain gages, ball bearing with lever arrangement, means to study the stress and strains produced in the material and arrangement to plot the frequency Vs displacement curves. The apparatus is used to study the bending and torsional effects produced in the structural specimens under different loading conditions.

Full Text	Field of the Invention;- The present invention relates to a apparatus for testing a structural specimen made up of concrete or steel subject to combined bending and torsion. Description to prior Art:- The presence of loading which produces simultaneous bending and torsion in a member means that some degree of Interaction between the two effects will occur. In case of bending plus torsion, the angle of twist (0) caused by the torsion is amplified by the bending moment, inducing additional warping moment and torsional shear. EP1087278 disclose method of generating control data for bending and torsion apparatus. The proposal for software program such as Numerical control program was given for collecting data and transferring to the processor and computer for analysis. US Pat No.4722223 dealing with Vibration testing of panel products, the method of panel support restricts the measurement to a single panel property, namely the modulus of elasticity from the single impact that produces panel vibration. DE 37 16 215 Al reveals a rotating bending test equipment also Torsion loading mechanism for introducing a circulating bending moment and a torsion loading into a test specimen. JP 2004150976 A reveals load test equipment for a torsion bending and axle load. JP 200227392 A reveals a combined torsion bending strain test machine. JP 7260652 A reveals a static's load tester. JP 61014541 A reveals Torsions and bending test machine. From the JP 4232441 it is actually well-known to bring to the production of a torsion vibration a sample at their two ends by means of electric motors in rotation and to detect the angles of rotation of the engines over function givers. Devices of this kind, with which the two electric motors with different number of revolutions, coupled at in each case an end of the sample, are operated, are particularly suitable for examining wires. From the EP 0,410,370 a device is well-known, with which a sample at in each case an end is shiftable by means of an electric motor in turn, whereby the rotating motion of an electric motor, which is coupled with an end of the sample, can by means of a blocking device be blocked and suddenly again released. The prior Art concerning complex bending and torsional effects and the theory applicable to torsional vibration are known to be applicable to rod like material of circular or rectangular cross section, but it has not been known to be applicable to rolled steel sections and products of different shapes, also it should be pointed out that the combined bending and torsion technique in the prior art requires multiple impacts and sensors to generate, capture and separate the two types of signals. Summary of Invention:- The invention relates to a apparatus for testing structural specimen subjected to bending and torsion. In accordance with one aspect of the present invention there is provided a method of testing the quality of structural specimen i.e. RSJ, solid section and composite section made of steel, concerte or composite material comprising. 1. Integrated strong floor system with extended floor provision. 2.Portal load frame system with minimum two no's of hydraulic actuator with point load and UDL load system arrangement. 3.Column fixed in floor for supporting the grip and fixtures (optional) with grip control system fixed on floor. 4.Resistance strain gages rosette with strain gage indicator box fixed on side frame of portal frame and attached with software for plotting displacement Vs frequency for different rosettes. 5.Position measurement digital gages with moveable attachment. 6.Ball bearing with lever arrangement at one side of grip for torsional moment. In accordance with another aspect of present invention there is provided a method for testing structural specimens under combined effect of bending and torsion comprising :- (a) Supporting the structural specimens in the support system with different end conditions (provision as required). (b) Fixing the rosette at top and bottom of the specimens with gel and connect them with strain indication box fixed on left and right side of the frame. (c) Placing the loading system in term of hydraulic actuator hanging from portal frame. (d) Positioning the digital strain gages on the beam to study the position of element at different interval of length. (e) Introduce required loading to produce bending moment and introducing required torsional moment at the end from ball bearing with lever arm arrangement to produce torsional moment. (f) Stop loading at point of maximum displacement allowed as per act, and note down the strain produced at different strain gauges and note down the angle of twist for different point of drift or point of failure. List of Drawings :- Fig 1. is a diagrammatic elevation view of an apparatus provided in accordance with the present invention. Fig-2. is right hand elevation view of fig 1, Fig-3. is an enlarge view of grip system with structure element. Fig-4. is a perspective view illustrating a machine co-ordinate system set on the structure element with torsional moment effect. Fig.5:- 30° Rosette strain gage Configuration Fig-6- Side view of beam with rosette position Fig-7- Top view of beam with strain gage location and number. Detailed Description of preferred Embodiment:- These are illustrated in figs 1, 2, 3 and 4 apparatus provided by the present invention for testing specimens, or RSJ. The apparatus is adopted for testing the structural specimens i.e. beam made up on Rolled steel Joists, channels, concrete and composite material subjected to combined bending and torsional effects referring to figs 1 to 3. The apparatus includes a rigid frame 1 that includes vertical posts (a, b) horizontally-spaced apart interconnected by horizontal member. Posts are rigidly fixed on the integrated strong floor with extended floor system, with nut and bolt arrangement at bottom and connected with plate Girder of sufficient strength at top. At least two hydraulic actuators (5) with rolling and fixture system are running on the horizontal beam. A mild steel loading frame 2 (a, b) is used to support the structural specimen according to different end conditions. The loading arm is rigidly attached to free end of the beam. It has a movable collar (3, 3') allowing both the bending and the combined bending and torsion to be examined. At least two digital displacement indicators (4,4') gages are fixed to the loading arm. As the beam deflects the gage moves with the beam and displacement from the reference frame is indicated. These gages are used to measure both deflection (h) and angle of twist (0) at the end of the beam as shown. At least two rosette strain gages are mounted in 45° orientation along the longitudinal axis of the beam. The strain indicator box (11) allows the rosette strains to be read digitally. The strain indicator box houses the register (R3), the variables register (R4) power supply and the galvanometer. The bridge can be balanced by adjusting R4. For rosette, the gage factor is 2.03 ± 1.00% The structural specimen RSJ or other structural specimen are position in the apparatus i.e. for simply supported end condition fixed at one grip and rolling on other side attached with torsional lever arm to produce torsional moment in the specimen, similarly both end fixed and cantilever end condition are maintained. Hydraulic actuators are positioned on the top surface of the structural element to produce bending effects. At least two rosettes are mounted on top, two on bottom just opposite to loading and two on the vertical side for studying the twist strain as per study conditions. All the rosette strain gages are attached with strain indicator box. The bridge can be balanced by adjusting R4. Introduce loading through actuator and required torsional moments are produced in the specimen from end through ball bearing with lever arm attachment for torsional moment. Note down the different angle of twist for different drift and strain at different loading condition so as to study the failure criteria. Graph between stress Vs strain should be produced for different loading. These displacement charts for flexural and torsional hysters are used to find out the reliability of that structural element. These charts help in design of a structure so that for a particular rate of reliability maximum capacity of the specimen was fixed. Or the structured elements should be designed for the particular amount of reliability and particular loading condition as per field requirements. Claims:- 1. Apparatus for testing structural elements subjected to bending and torsion comprising. (a) Portal load frame system fixed with integrated strong floor system with a loading arrangement means. (b) Support structure columns fixed on the floor system with specimen clamping means. (c) Resistance strain gage indicator box fixed on side frame of portal with extended clips for resettle (d) Position measuring digital strain gage hanging from the loading frame to measure the position of element during loading conditions. (e) Ball bearing with lever arm arrangement fixed on one side of supporting structure to introduce torsional moment effects. 2:- The apparatus as claimed in claim 1, wherein portal load frame and supporting structure are made up of plates. 3:- The apparatus as claimed in claim 1, wherein the clamping means is grip and fixture arrangement with grip control device fixed perpendicular to the support structure. 4:- The apparatus as claimed in claim 1, wherein rosette strain gage are attached with software to plot stress Vs strain curves. 5:- The apparatus as claimed in claim 1, where in strain gages are of higher accuracy. 6:- The method of testing the structural element with the apparatus as claimed in claim 1 comprising steps of (a) Supporting the structural specimens in the support system with different end conditions (provision as required). (b) Fixing the rosette at top and bottom of the specimens with gel and connect them with strain indication box fixed on left and right side of the frame. (c) Placing the loading system in term of hydraulic actuator hanging from portal frame. (d) Positioning the digital strain gages on the beam to study the position of element at different interval of length. (e) Introduce required loading to produce bending moment and introducing required torsional moment at the end from ball bearing with lever arm arrangement to produce torsional moment. (f) Stop loading at point of maximum displacement allowed as per act, and note down the strain produced at different strain gauges and note down the angle of twist for different point of drift or point of failure. 7:- The method of testing the structural element as claimed in claims 6, wherein at least two rosettes are mounted in 45" orientation along the longitudinal axis of beam. 8:- The method of testing the structural element as claimed in claim 6, where in lever arm is rotated in clock-wise direction to produce torsional moments 9:- The Apparatus for testing structural elements subjected to bending and torsion as herein described with reference to the accompanying drawings. 10:- The method for testing structural elements subjected to bending and torsion as herein described with reference to the accompanying drawings.

Full Text

Field of the Invention;-
The present invention relates to a apparatus for testing a structural specimen made up of concrete or steel subject to combined bending and torsion. Description to prior Art:-
The presence of loading which produces simultaneous bending and torsion in a member means that some degree of Interaction between the two effects will occur. In case of bending plus torsion, the angle of twist (0) caused by the torsion is amplified by the bending moment, inducing additional warping moment and torsional shear.
EP1087278 disclose method of generating control data for bending and torsion apparatus. The proposal for software program such as Numerical control program was given for collecting data and transferring to the processor and computer for analysis.
US Pat No.4722223 dealing with Vibration testing of panel products, the method of panel support restricts the measurement to a single panel property, namely the modulus of elasticity from the single impact that produces panel vibration.
DE 37 16 215 Al reveals a rotating bending test equipment also Torsion loading mechanism for introducing a circulating bending moment and a torsion loading into a test specimen.
JP 2004150976 A reveals load test equipment for a torsion bending and axle load. JP 200227392 A reveals a combined torsion bending strain test machine. JP 7260652 A reveals a static's load tester.
JP 61014541 A reveals Torsions and bending test machine.
From the JP 4232441 it is actually well-known to bring to the production of a torsion vibration a sample at their two ends by means of electric motors in rotation and to detect the angles of rotation of the engines over function givers. Devices of this kind, with which the two electric motors with different number of revolutions, coupled at in each case an end of the sample, are operated, are particularly suitable for examining wires.
From the EP 0,410,370 a device is well-known, with which a sample at in each case an end is shiftable by means of an electric motor in turn, whereby the rotating motion of an electric motor, which is coupled with an end of the sample, can by means of a blocking device be blocked and suddenly again released.
The prior Art concerning complex bending and torsional effects and the theory applicable to torsional vibration are known to be applicable to rod like material of circular or rectangular cross section, but it has not been known to be applicable to rolled steel sections and products of different shapes, also it should be pointed out that the combined bending and torsion technique in the prior art requires multiple impacts and sensors to generate, capture and separate the two types of signals.
Summary of Invention:-
The invention relates to a apparatus for testing structural specimen subjected to bending and torsion. In accordance with one aspect of the present invention
there is provided a method of testing the quality of structural specimen i.e. RSJ, solid section and composite section made of steel, concerte or composite material comprising. 1. Integrated strong floor system with extended floor provision. 2.Portal load frame system with minimum two no's of hydraulic actuator with
point load and UDL load system arrangement. 3.Column fixed in floor for supporting the grip and fixtures (optional) with grip
control system fixed on floor.
4.Resistance strain gages rosette with strain gage indicator box fixed on side frame of portal frame and attached with software for plotting displacement Vs frequency for different rosettes.
5.Position measurement digital gages with moveable attachment. 6.Ball bearing with lever arrangement at one side of grip for torsional moment. In accordance with another aspect of present invention there is provided a method for testing structural specimens under combined effect of bending and torsion comprising :-
(a) Supporting the structural specimens in the support system with different end
conditions (provision as required).
(b) Fixing the rosette at top and bottom of the specimens with gel and connect
them with strain indication box fixed on left and right side of the frame.
(c) Placing the loading system in term of hydraulic actuator hanging from portal
frame.
(d) Positioning the digital strain gages on the beam to study the position of
element at different interval of length.
(e) Introduce required loading to produce bending moment and introducing
required torsional moment at the end from ball bearing with lever arm
arrangement to produce torsional moment.
(f) Stop loading at point of maximum displacement allowed as per act, and note
down the strain produced at different strain gauges and note down the angle of
twist for different point of drift or point of failure.
List of Drawings :-
Fig 1. is a diagrammatic elevation view of an apparatus provided in accordance with the
present invention.
Fig-2. is right hand elevation view of fig 1,
Fig-3. is an enlarge view of grip system with structure element.
Fig-4. is a perspective view illustrating a machine co-ordinate system set on the structure
element with torsional moment effect.
Fig.5:- 30° Rosette strain gage Configuration
Fig-6- Side view of beam with rosette position
Fig-7- Top view of beam with strain gage location and number.
Detailed Description of preferred Embodiment:-
These are illustrated in figs 1, 2, 3 and 4 apparatus provided by the present invention for testing specimens, or RSJ. The apparatus is adopted for testing the structural specimens i.e. beam made up on Rolled steel Joists, channels, concrete and composite material subjected to combined bending and torsional effects referring to figs 1 to 3. The apparatus includes a rigid frame 1 that includes vertical posts (a, b) horizontally-spaced apart interconnected by horizontal member. Posts are rigidly fixed on the
integrated strong floor with extended floor system, with nut and bolt arrangement at bottom and connected with plate Girder of sufficient strength at top.
At least two hydraulic actuators (5) with rolling and fixture system are running on the horizontal beam.
A mild steel loading frame 2 (a, b) is used to support the structural specimen according to different end conditions.
The loading arm is rigidly attached to free end of the beam. It has a movable collar (3, 3') allowing both the bending and the combined bending and torsion to be examined.
At least two digital displacement indicators (4,4') gages are fixed to the loading arm.
As the beam deflects the gage moves with the beam and displacement from the reference frame is indicated. These gages are used to measure both deflection (h) and angle of twist (0) at the end of the beam as shown.
At least two rosette strain gages are mounted in 45° orientation along the longitudinal axis of the beam. The strain indicator box (11) allows the rosette strains to be read digitally.
The strain indicator box houses the register (R3), the variables register (R4) power supply and the galvanometer. The bridge can be balanced by adjusting R4. For rosette, the gage factor is 2.03 ± 1.00%
The structural specimen RSJ or other structural specimen are position in the apparatus i.e. for simply supported end condition fixed at one grip and rolling on other side attached with torsional lever arm to produce torsional moment in the specimen,
similarly both end fixed and cantilever end condition are maintained. Hydraulic actuators are positioned on the top surface of the structural element to produce bending effects. At least two rosettes are mounted on top, two on bottom just opposite to loading and two on the vertical side for studying the twist strain as per study conditions. All the rosette strain gages are attached with strain indicator box. The bridge can be balanced by adjusting R4.
Introduce loading through actuator and required torsional moments are produced in the specimen from end through ball bearing with lever arm attachment for torsional moment. Note down the different angle of twist for different drift and strain at different loading condition so as to study the failure criteria. Graph between stress Vs strain should be produced for different loading. These displacement charts for flexural and torsional hysters are used to find out the reliability of that structural element. These charts help in design of a structure so that for a particular rate of reliability maximum capacity of the specimen was fixed. Or the structured elements should be designed for the particular amount of reliability and particular loading condition as per field requirements.

Claims:-
1. Apparatus for testing structural elements subjected to bending and torsion comprising.
(a) Portal load frame system fixed with integrated strong floor system with a loading
arrangement means.
(b) Support structure columns fixed on the floor system with specimen clamping
means.
(c) Resistance strain gage indicator box fixed on side frame of portal with extended
clips for resettle
(d) Position measuring digital strain gage hanging from the loading frame to measure
the position of element during loading conditions.
(e) Ball bearing with lever arm arrangement fixed on one side of supporting structure
to introduce torsional moment effects.
2:- The apparatus as claimed in claim 1, wherein portal load frame and supporting
structure are made up of plates.
3:- The apparatus as claimed in claim 1, wherein the clamping means is grip and fixture
arrangement with grip control device fixed perpendicular to the support structure.
4:- The apparatus as claimed in claim 1, wherein rosette strain gage are attached with
software to plot stress Vs strain curves.
5:- The apparatus as claimed in claim 1, where in strain gages are of higher accuracy.
6:- The method of testing the structural element with the apparatus as claimed in claim 1
comprising steps of
(a) Supporting the structural specimens in the support system with different end
conditions (provision as required).
(b) Fixing the rosette at top and bottom of the specimens with gel and connect them
with strain indication box fixed on left and right side of the frame.
(c) Placing the loading system in term of hydraulic actuator hanging from portal
frame.
(d) Positioning the digital strain gages on the beam to study the position of element at
different interval of length.
(e) Introduce required loading to produce bending moment and introducing required
torsional moment at the end from ball bearing with lever arm arrangement to produce
torsional moment.
(f) Stop loading at point of maximum displacement allowed as per act, and note down
the strain produced at different strain gauges and note down the angle of twist for
different point of drift or point of failure.
7:- The method of testing the structural element as claimed in claims 6, wherein at least
two rosettes are mounted in 45" orientation along the longitudinal axis of beam.
8:- The method of testing the structural element as claimed in claim 6, where in lever arm
is rotated in clock-wise direction to produce torsional moments
9:- The Apparatus for testing structural elements subjected to bending and torsion as
herein described with reference to the accompanying drawings.
10:- The method for testing structural elements subjected to bending and torsion as herein
described with reference to the accompanying drawings.

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Patent Number

213751

Indian Patent Application Number

1076/DEL/2007

PG Journal Number

03/2008

Publication Date

18-Jan-2008

Grant Date

11-Jan-2008

Date of Filing

17-May-2007

Name of Patentee

DR. VIJAY KUMAR SEHGAL

Applicant Address

PROFESSOR AND CHAIRMAN, CIVIL ENGINEERING DEPARTMENT, NATIONAL INSTITUTE OF TECHNOLOGY, KURUKSHETRA, HARYANA,-136119, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	SH. SHANKAR DYAL BHATNAGAR	1628/5, NEAR GOVT. GIRLS SEN.SEC.SCHOOL, CHOTTA BAZAR, THANESAR, KURUKSHETRA, HARYANA-136 118

PCT International Classification Number

G01N3/20

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA