CN110617934A - Method for measuring torsional wave of flange I-beam with different thicknesses - Google Patents

Method for measuring torsional wave of flange I-beam with different thicknesses Download PDF

Info

Publication number
CN110617934A
CN110617934A CN201910949349.2A CN201910949349A CN110617934A CN 110617934 A CN110617934 A CN 110617934A CN 201910949349 A CN201910949349 A CN 201910949349A CN 110617934 A CN110617934 A CN 110617934A
Authority
CN
China
Prior art keywords
strain
torsional
flange
wave
flower
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201910949349.2A
Other languages
Chinese (zh)
Other versions
CN110617934B (en
Inventor
胡豪
黄怀英
刘征
熊俊涛
刘庆彬
刘群根
孙福强
杨勇
黄瑞泉
王进剑
朱利媛
陈雄昕
田占宝
黄鑫
黄凌翔
胡杨坡
王永昌
刘序理
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jiangxi Hongdu Aviation Industry Group Co Ltd
Original Assignee
Jiangxi Hongdu Aviation Industry Group Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jiangxi Hongdu Aviation Industry Group Co Ltd filed Critical Jiangxi Hongdu Aviation Industry Group Co Ltd
Priority to CN201910949349.2A priority Critical patent/CN110617934B/en
Publication of CN110617934A publication Critical patent/CN110617934A/en
Application granted granted Critical
Publication of CN110617934B publication Critical patent/CN110617934B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M5/00—Investigating the elasticity of structures, e.g. deflection of bridges or air-craft wings
    • G01M5/0041—Investigating the elasticity of structures, e.g. deflection of bridges or air-craft wings by determining deflection or stress
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M7/00—Vibration-testing of structures; Shock-testing of structures
    • G01M7/08—Shock-testing

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

A method for measuring torsional wave of I-beam with unequal-thickness flange includes selecting torsional center of cross section of I-beam as coordinate origin to set up coordinate system, decomposing stress wave on cross section of I-beam, deducing relation between corresponding points of constraint torsional stress on top flange and bottom flange of I-beam with unequal-thickness flange, multiplying by correction term to obtain shear stress caused by constraint torsional strain of strain gauge measurement, combining shear stress with coefficient of cross section of I-beam to obtain torsional wave of cross section of I-beam.

Description

Method for measuring torsional wave of flange I-beam with different thicknesses
Technical Field
The invention relates to the technical field of load measurement of airplane design mechanical structures, in particular to a method for measuring torsional waves of flange I-beams with different thicknesses.
Background
I-beams in mechanical structures are widely used, such as automobile frames, engine piston rods and the like, and the actual structures often need to use I-beams with different thicknesses of upper and lower flanges according to special use conditions. Due to the characteristics of the I-beam, the I-beam cannot bear larger torsional load, so that accurate measurement of torsional waves of the I-beam is very important in structural design, especially under the condition of complex impact load, the measurement of the torsional waves borne by the I-beam plays a vital role in cross section optimization design and simulation calculation. Meanwhile, the measured torsional wave is caused by impact load, the propagation speed of the stress wave is high, the stress wave is sensitive to boundary conditions, and the torsional wave of the unequal-thickness flange I-beam is difficult to measure in both methods and actual operation due to the particularity of the cross section shape of the unequal-thickness flange I-beam.
The traditional method for measuring the impact load is to use a force measuring device to impact a test piece, and obtain the load borne by the structural beam through the load measured by the force measuring device. Patent No. 201711231744.4 discloses a method for measuring impact load of a beam with a double symmetrical section, which has poor effect of measuring torsional waves borne by an I-beam with a flange with different thickness, and chinese patent No. 201410597656.6 discloses a method for testing load impact load of an airplane wheel bearing, which measures quasi-static load and is not suitable for measuring stress waves.
In conclusion, the existing measuring methods cannot effectively measure the torsional wave of the I-beam with unequal-thickness flanges under the impact load.
Disclosure of Invention
The invention aims to provide a method for measuring torsional waves of an I-beam with unequal-thickness flanges, so as to solve the problems in the background technology.
The technical problem solved by the invention is realized by adopting the following technical scheme:
a method for measuring torsional wave of an I-beam with unequal-thickness flange is provided, wherein the wall thickness of an upper flange of the cross section of the I-beam with unequal-thickness flange is t1The wall thickness of the lower flange is t2Web wall thickness of t3The width of the upper flange and the width of the lower flange are both b, the distance from the center line of the upper flange to the center line of the lower flange is h, and the method comprises the following specific steps:
1) establishing a coordinate system
Selecting a torsional center of the cross section of the I-beam as a coordinate origin o, wherein an x axis is parallel to a center line of a flange and faces right, a y axis is upward along a symmetrical axis, and a z axis is determined according to a right-hand rule;
pasting strain patterns on the cross section of the I-steel with unequal-thickness flange, wherein the first strain patterns S1A second strain flower S adhered to the right lower surface of the upper flange2Third strain rosette S adhered to left upper surface of upper flange3A fourth strain flower S adhered to the left upper surface of the lower flange4A fifth strain flower S adhered to the right lower surface of the lower flange5The sixth strain rosette S adhered to the left surface of the web6Adhered to the right surface of the web plate and provided with a first strain flower S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4Equal distance to y-axis, fifth strain rosette S5And the sixth strain flower S6Equal distance to the x-axis;
first strain flower S1The three strain gauges are respectively a first strain gauge flower sheet S1_1First strain rosette two pieces S1_2And the first strain flower three sheets S1_3；S1_1、S1_2And S1_3The arrangement sequence of the patch points and the external normal line of the patch points form a right-hand rule; second strain rosette S2Sixth Strain flower S6Paster direction, numbering rule and first strain flower S1The same;
to obtain a more ideal measurement result, the first strain rosette S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4The first strain rosette S is selected to be as close to the y axis as possible, but because the corner of the i-beam is easy to generate stress concentration, the intersection of the flange and the web is avoided, and the first strain rosette S is selected firstly1The second strain flower S2And the third strain flower S3And a fourth strain flower S4A fifth strain rosette S at a distance b/4 from the y-axis5And the sixth strain flower S6The distance between the flange and the flange is h/2, and the values of b/4 and h/2 are not absolute, so that the distance can be slightly adjusted according to actual conditions in practical application;
2) deducing and constraining the torsional shear stress at the corresponding points C of the upper flange and the lower flange of the I-beam with unequal-thickness flangesiAnd CjThe relationship between
Decomposing stress wave into axial compression/tension on cross section of I-beamExtensional wave FNBending wave Mx、MyShear wave FQx、FQyTorsion wave T;
for most metallic materials, neglecting the strain rate effect of the metallic material in the low-speed impact, linear elastic range, the material constant of the i-beam: elastic modulus E, Poisson's ratio mu, shear modulus G, andthe material constants can be obtained by checking according to a material manual or by testing, and the corresponding section constants of the I-beam with the flange of different thicknesses can be calculated according to material mechanics according to the size of the cross section of the I-beam: main sectorial area omega of cross section, sectorial inertia moment I of cross sectionωPartial area fanning static moment SωTorsional stiffness GI of free torsion of the cross sectionn；
The distance between the upper flange and the lower flange from the y axis is xCCorresponding point C ofiAnd CjThe fanning static moments are respectively as follows:
an upper flange:
a lower flange:
then, the corresponding points C of the upper flange and the lower flange are obtainediAnd CjThe fan static moment is equal in size and opposite in direction;
the restraint torsional shear stress is:
wherein: k is 1 or 2;
then, the corresponding points C of the upper flange and the lower flange are obtainediAnd CjThe corresponding constraint torsion shear stress relationship is as follows:
therefore, the constraint torsional shear stress is at the corresponding point C of the upper flange and the lower flange of the I-beam with unequal-thickness flangesiAnd CjThe relationship between the thickness and the size is in inverse proportion, and the directions are opposite;
3) calculating torsional wave of cross section of I-beam
According to the characteristics of the cross section of the I-beam, the strain of each strain flower stuck to the cross section of the I-beam is measured within the linear elastic range as follows:
step one, calculating the shear strain of each strain flower, as shown in formula (5);
second, by the fifth strain rosette S5And a sixth strain flower S6The shear strain of the point calculates the shear stress caused by free torsion, as shown in formula (6);
thirdly, according to the deformation characteristics of the cross section of the I-beam caused by different loads, particularly the C corresponding to the upper flange and the lower flangeiPoint and CjThe magnitude of the point constraint torsion shear stress is in inverse proportion to the thickness of the flange and in opposite direction, and the constraint torsion measurement is split: firstly, for the first strain flower S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4The measured shear stress is superimposed to eliminate bending wave Mx、MyShear wave FQx、FQyAxial compression/tension wave FNAnd free torsional wave TnInduced stress; then the C corresponding to the upper flange and the lower flange is led out due to the step 2)iPoint and CjThe magnitude of the point constraint torsional shear stress is in inverse proportion to the thickness of the flange and in opposite directions, and then multiplied by a correction termObtaining a first strain flower S1Or the second strain flower S2Measured shear stress induced by constrained torsionOrAs shown in formula (7);
the fourth step, calculating the free torsional wave TnAnd restrain torsional wave TωAs shown in formulas (8) to (9);
fifthly, calculating a cross section torsional wave T as shown in a formula (10);
the shear strain at each patch point was calculated as:
γSk＝2εSk_2-(εSk_1+εSk_3) (5)
wherein k is the dot number of the patch;
free torsional shear stress:
restraining torsional shear stress:
the I-beam with unequal thickness flanges comprises a full bridge formed by the data processing of the constraint torsional shear stress and the data processing, and then multiplied by the correction quantityIf the thickness difference between the upper flange and the lower flange is large, the correction quantity can obviously improve the precision of the measurement result;
for the I-beam with unequal thickness flanges, calculating the stress caused by various loads, and then solving the torsional wave according to the coefficient of the cross section of the I-beam:
free torsional wave Tn：
Restraint torsional wave Tω：
Wherein t is the thickness of the web,is a first strain flower S1The flabellar static moment at point;
the torsional wave of the cross section of the I-shaped beam is as follows:
has the advantages that: the method selects the torsional center of the cross section of the I-beam as a coordinate origin to establish a coordinate system, then decomposes the stress wave on the cross section of the I-beam, deduces the relation between corresponding points of the constraint torsional shear stress on the upper flange and the lower flange of the I-beam with unequal thickness flanges, multiplies the relation by a correction term to obtain the shear stress caused by the constraint torsion of strain gage measurement, and finally obtains the torsional wave of the cross section of the I-beam by combining the shear stress with the cross section coefficient of the I-beam.
Drawings
Fig. 1 is a schematic diagram of a patch spot in a preferred embodiment of the invention.
FIG. 2 is a schematic view of the top surface of the flange in the preferred embodiment of the present invention.
Fig. 3 is a schematic view of the orientation of the patch under the flange in the preferred embodiment of the invention.
FIG. 4 is a schematic view of the direction of the patches on the right surface of the web in the preferred embodiment of the invention.
Fig. 5 is a schematic view of the left surface patch orientation of the web in the preferred embodiment of the invention.
FIG. 6 is a cross-sectional view of a specific fabric sheet in a preferred embodiment of the invention.
Fig. 7 is a fanning view of an i-beam with flanges of different thicknesses in a preferred embodiment of the invention.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.
A method for measuring torsional wave of an I-beam with unequal-thickness flanges is disclosed, wherein the cross section shape of the I-beam with unequal-thickness flanges is shown in figure 1, a central line 2 of the cross section 1 of the I-beam with unequal-thickness flanges is shown by a dotted line in figure 1, and the wall thickness of an upper flange of the cross section of the I-beam with unequal-thickness flanges is t1The wall thickness of the lower flange is t2Web wall thickness of t3The width of the upper flange and the width of the lower flange are both b, the distance from the center line of the upper flange to the center line of the lower flange is h, and the method comprises the following specific steps:
1) establishing a coordinate system
Selecting a torsional center of the cross section of the I-beam as a coordinate origin o, wherein an x axis is parallel to a center line of a flange and faces right, a y axis is upward along a symmetrical axis, and a z axis is determined according to a right-hand rule;
pasting strain patterns on the cross section of the I-steel with unequal-thickness flange, wherein the first strain patterns S1A second strain flower S adhered to the right lower surface of the upper flange2Third strain rosette S adhered to left upper surface of upper flange3A fourth strain flower S adhered to the left upper surface of the lower flange4A fifth strain flower S adhered to the right lower surface of the lower flange5The sixth strain rosette S adhered to the left surface of the web6Adhered to the right surface of the web plate and provided with a first strain flower S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4Equal distance to y-axis, fifth strain rosette S5And the sixth strain flower S6Equal distance to the x-axis;
first strain flower S1The three strain gauges are respectively a first strain gauge flower sheet S1_1First strain rosette two pieces S1_2And the first strain flower three sheets S1_3；S1_1、S1_2And S1_3The arrangement sequence of the patch points and the external normal line of the patch points form a right-hand rule; second strain rosette S2And the third strain flower S3The direction of the patch is shown in figure 2, the first strain flower S1And the fourth strain flower S4The patch orientation is as shown in FIG. 3, fifthStrain flower S5The patch direction is shown in FIG. 4, and the sixth strain flower S6The patch orientation is shown in fig. 5; a specific example of a patch is shown in fig. 6;
in order to obtain a more ideal measurement result, the first strain rosette S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4The y-axis should be as close as possible, but since the corners of the i-beam are prone to stress concentration, the intersection between the flange and the web is avoided, so the first strain rosette S may be selected first1The second strain flower S2And the third strain flower S3And a fourth strain flower S4A fifth strain rosette S at a distance b/4 from the y-axis5And the sixth strain flower S6The distance between the flange and the flange is h/2, and the values of b/4 and h/2 are not absolute, so that the distance can be slightly adjusted according to actual conditions in practical application;
2) deducing and constraining the torsional shear stress at the corresponding points C of the upper flange and the lower flange of the I-beam with unequal-thickness flangesiAnd CjThe relationship between
Decomposing stress wave into axial compression/tension wave F on cross section of I-beamNBending wave Mx、MyShear wave FQx、FQyThe torsional wave T is measured from the complex stress state of the unequal-thickness flange I-beam because the torsional property of the opening thin-wall component is weaker, so that the size of the torsional wave is most concerned in engineering under the impact load;
for most metallic materials, neglecting the strain rate effect of the metallic material in the low-speed impact, linear elastic range, the material constant of the i-beam: elastic modulus E, Poisson's ratio mu, shear modulus G, andthe material constants can be obtained by checking according to a material manual or by testing, and the corresponding section constants of the I-beam with the flanges of different thicknesses can be calculated according to the material mechanics according to the size of the cross section of the I-beam: main sectorial area omega of cross section, sectorial inertia moment I of cross sectionωPartial area fanning static moment SωTorsional stiffness GI of free torsion of the cross sectionn；
In order to measure the torsional wave, the relation between the restraint torsional shear stress of the upper flange and the lower flange is calculated, and the distance between the upper flange and the lower flange and the y axis is xCCorresponding point C ofiAnd CjThe fanning static moments are respectively as follows:
an upper flange:
a lower flange:
then, the corresponding points C of the upper flange and the lower flange are obtainediAnd CjThe fan static moment is equal in size and opposite in direction;
the restraint torsional shear stress is:
wherein: k is 1 or 2;
then, the corresponding points C of the upper flange and the lower flange are obtainediAnd CjThe corresponding constraint torsion shear stress relationship is as follows:
therefore, the constraint torsional shear stress is at the corresponding point C of the upper flange and the lower flange of the I-beam with unequal-thickness flangesiAnd CjThe relationship between the thickness and the size is in inverse proportion, and the directions are opposite;
3) calculating torsional wave of cross section of I-beam
According to the characteristics of the cross section of the I-beam shown in the figure 1, the strain of each strain gage of the cross section of the I-beam is measured within the linear elasticity range as follows:
step one, calculating the shear strain of each strain flower, as shown in formula (5);
second, by the fifth strain rosette S5And a sixth strain flower S6The shear strain of the point calculates the shear stress caused by free torsion, as shown in formula (6);
thirdly, according to the deformation characteristics of the cross section of the I-beam caused by different loads, particularly the C corresponding to the upper flange and the lower flangeiPoint and CjThe magnitude of the point constraint torsion shear stress is in inverse proportion to the thickness of the flange and in opposite direction, and the constraint torsion measurement is split: firstly, for the first strain flower S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4The measured shear stress is superimposed to eliminate bending wave Mx、MyShear wave FQx、FQyAxial compression/tension wave FNAnd free torsional wave TnInduced stress; then the C corresponding to the upper flange and the lower flange is led outiPoint and CjThe magnitude of the point constraint torsional shear stress is in inverse proportion to the thickness of the flange and in opposite directions, and then multiplied by a correction termObtaining a first strain flower S1Or the second strain flower S2Measured shear stress induced by constrained torsionOrAs shown in formula (7);
the fourth step, calculating the free torsional wave TnAnd restrain torsional wave TωAs shown in formulas (8) to (9);
fifthly, calculating a cross section torsional wave T as shown in a formula (10);
as shown in fig. 2, the shear strain at each strain flower is calculated as:
γSk＝2εSk_2-(εSk_1+εSk_3) (5)
wherein k is the dot number of the patch;
free torsional shear stress:
restraining torsional shear stress:
the I-beam with unequal thickness flanges comprises a full bridge formed by processing the constraint torsional shear stress data and then multiplied by the correction quantityIf the thickness difference between the upper flange and the lower flange is large, the correction quantity can obviously improve the precision of the measurement result;
for the I-beam with unequal thickness flanges, calculating the stress caused by various loads, and then solving the torsional wave according to the coefficient of the cross section of the I-beam:
free torsional wave Tn：
Restraint torsional wave Tω：
Wherein t is the thickness of the web,is a first strain flower S1The flabellar static moment at point;
the torsional wave of the cross section of the I-shaped beam is as follows:
the foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (8)

1. A method for measuring torsional wave of an I-beam with unequal-thickness flanges is characterized in that the wall thickness of an upper flange of the cross section of the I-beam with unequal-thickness flanges is t1The wall thickness of the lower flange is t2Web wall thickness of t3The width of the upper flange and the width of the lower flange are both b, the distance from the center line of the upper flange to the center line of the lower flange is h, and the method comprises the following specific steps:
1) establishing a coordinate system
Selecting a torsional center of the cross section of the I-beam as a coordinate origin o, wherein an x axis is parallel to a center line of a flange and faces right, a y axis is upward along a symmetrical axis, and a z axis is determined according to a right-hand rule;
pasting strain patterns on the cross section of the I-steel with unequal-thickness flange, wherein the first strain patterns S1A second strain flower S adhered to the right lower surface of the upper flange2Third strain rosette S adhered to left upper surface of upper flange3A fourth strain flower S adhered to the left upper surface of the lower flange4A fifth strain flower S adhered to the right lower surface of the lower flange5The sixth strain rosette S adhered to the left surface of the web6The right surface of the web plate is pasted;
2) deducing and constraining the torsional shear stress at the corresponding points C of the upper flange and the lower flange of the I-beam with unequal-thickness flangesiAnd CjThe relationship between
Decomposing stress wave into axial compression/tension wave F on cross section of I-beamNBending wave Mx、MyShear wave FQx、FQyTorsion wave T;
for most metallic materials, neglecting the strain rate effect of the metallic material in the low-speed impact, linear elastic range, the material constant of the i-beam: modulus of elasticity E, Poisson's ratioμ, shear modulus G, andthe material constants can be obtained by checking according to a material manual or by testing, and the corresponding section constants of the I-beam with the flange of different thicknesses can be calculated according to material mechanics according to the size of the cross section of the I-beam: main sectorial area omega of cross section, sectorial inertia moment I of cross sectionωPartial area fanning static moment SωTorsional stiffness GI of free torsion of the cross sectionn；
The distance between the upper flange and the lower flange from the y axis is xCCorresponding point C ofiAnd CjThe fanning static moments are respectively as follows:
an upper flange:
a lower flange:
then, the corresponding points C of the upper flange and the lower flange are obtainediAnd CjThe fan static moment is equal in size and opposite in direction;
the restraint torsional shear stress is:
wherein: k is 1 or 2;
then, the corresponding points C of the upper flange and the lower flange are obtainediAnd CjThe corresponding constraint torsion shear stress relationship is as follows:
therefore, the constraint torsional shear stress is at the corresponding point C of the upper flange and the lower flange of the I-beam with unequal-thickness flangesiAnd CjThe relationship between the thickness and the size is in inverse proportion, and the directions are opposite;
3) calculating torsional wave of cross section of I-beam
According to the characteristics of the cross section of the I-beam, the strain of each strain flower stuck to the cross section of the I-beam is measured within the linear elastic range as follows:
firstly, calculating the shear strain of each strain flower;
second, by the fifth strain rosette S5And a sixth strain flower S6The shear strain of the point calculates the shear stress caused by free torsion;
thirdly, according to the deformation characteristics of the cross section of the I-beam caused by different loads, particularly the C corresponding to the upper flange and the lower flangeiPoint and CjThe magnitude of the point constraint torsion shear stress is in inverse proportion to the thickness of the flange and in opposite direction, and the constraint torsion measurement is split: firstly, for the first strain flower S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4The measured shear stress is superimposed to eliminate bending wave Mx、MyShear wave FQx、FQyAxial compression/tension wave FNAnd free torsional wave TnInduced stress; then the C corresponding to the upper flange and the lower flange is led out due to the step 2)iPoint and CjThe magnitude of the point constraint torsional shear stress is in inverse proportion to the thickness of the flange and in opposite directions, and then multiplied by a correction termObtaining a first strain flower S1Or the second strain flower S2Measured shear stress induced by constrained torsionOr
The fourth step, calculating the free torsional wave TnAnd restrain torsional wave Tω；
The fifth step, according to the free torsional wave T of the fourth stepnAnd restrain torsional wave TωAnd calculating the cross-section torsional wave T.
2. The method for measuring the torsional wave of the I-beam with unequal-thickness flanges according to claim 1, wherein in the step 1), the first strain rosette S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4Equal distance to the y-axis.
3. The method for measuring torsional waves of I-beams with unequal-thickness flanges according to claim 2, wherein the first strain rosette S1The second strain flower S2And the third strain flower S3And a fourth strain flower S4The distance to the y-axis is b/4.
4. The method for measuring the torsional wave of the I-beam with unequal-thickness flanges according to claim 1, wherein in the step 1), a fifth strain rosette S5And the sixth strain flower S6Equal distance to the x-axis.
5. The method for measuring the torsional wave of the I-beam with unequal-thickness flanges according to claim 1, wherein in the step 1), a fifth strain rosette S5And the sixth strain flower S6The distance to the flange is h/2.
6. The method for measuring the torsional wave of the I-beam with unequal-thickness flanges according to claim 1, wherein in the step 1), the first strain rosette S1The three strain gauges are respectively a first strain gauge flower sheet S1_1First strain rosette two pieces S1_2And the first strain flower three sheets S1_3；S1_1、S1_2And S1_3The arrangement sequence of the patch points and the external normal line of the patch points form a right-hand rule; second strain rosette S2Sixth Strain flower S6Paster direction, numbering rule and first strain flower S1The same is true.
7. The method for measuring the torsional wave of the unequal-thickness flange I-beam according to claim 1, wherein in the step 3), the shear strain at each strain flower is calculated as:
γSk＝2εSk_2-(εSk_1+εSk_3) (5)
wherein k is the dot number of the patch;
free torsional shear stress:
restraining torsional shear stress:
for the I-beam with unequal thickness flanges, calculating the stress caused by various loads, and then solving the torsional wave according to the coefficient of the cross section of the I-beam:
free torsional wave Tn：
Restraint torsional wave Tω：
Wherein t is the thickness of the web,is a first strain flower S1The flabellar static moment at point;
the torsional wave of the cross section of the I-shaped beam is as follows:
8. the method for measuring the torsional wave of the I-beam with unequal-thickness flanges according to claim 1, wherein in the step 3), the I-beam with unequal-thickness flanges forms a full bridge by processing the data of the constrained torsional shear stress, and then multiplies the full bridge by the correction quantityIf the thickness difference between the upper flange and the lower flange is large, the correction quantity can obviously improve the precision of the measurement result.
CN201910949349.2A 2019-10-08 2019-10-08 Method for measuring torsional wave of flange I-beam with different thicknesses Active CN110617934B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910949349.2A CN110617934B (en) 2019-10-08 2019-10-08 Method for measuring torsional wave of flange I-beam with different thicknesses

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910949349.2A CN110617934B (en) 2019-10-08 2019-10-08 Method for measuring torsional wave of flange I-beam with different thicknesses

Publications (2)

Publication Number Publication Date
CN110617934A true CN110617934A (en) 2019-12-27
CN110617934B CN110617934B (en) 2021-08-20

Family

ID=68925163

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910949349.2A Active CN110617934B (en) 2019-10-08 2019-10-08 Method for measuring torsional wave of flange I-beam with different thicknesses

Country Status (1)

Country Link
CN (1) CN110617934B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112748008A (en) * 2020-12-29 2021-05-04 中国航空工业集团公司西安飞机设计研究所 I-beam tensile fatigue test piece and tensile fatigue test method
CN113051754A (en) * 2021-03-23 2021-06-29 同济大学建筑设计研究院(集团)有限公司 Design method for section of asymmetric flange H-shaped steel combination beam

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101560814A (en) * 2009-05-11 2009-10-21 宁波大学 Combined I-shaped girder and processing method thereof
CN203403596U (en) * 2013-07-18 2014-01-22 杭州博数土木工程技术有限公司 Continuous flanged beam with corrugated steel web steel structure
CN104359675A (en) * 2014-10-29 2015-02-18 西安航空制动科技有限公司 Method for testing load impact loading of aircraft wheel bearings
CN108106952A (en) * 2017-11-30 2018-06-01 江西洪都航空工业集团有限责任公司 A kind of disymmetry section shock loading measuring method of beam

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101560814A (en) * 2009-05-11 2009-10-21 宁波大学 Combined I-shaped girder and processing method thereof
CN203403596U (en) * 2013-07-18 2014-01-22 杭州博数土木工程技术有限公司 Continuous flanged beam with corrugated steel web steel structure
CN104359675A (en) * 2014-10-29 2015-02-18 西安航空制动科技有限公司 Method for testing load impact loading of aircraft wheel bearings
CN108106952A (en) * 2017-11-30 2018-06-01 江西洪都航空工业集团有限责任公司 A kind of disymmetry section shock loading measuring method of beam

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112748008A (en) * 2020-12-29 2021-05-04 中国航空工业集团公司西安飞机设计研究所 I-beam tensile fatigue test piece and tensile fatigue test method
CN113051754A (en) * 2021-03-23 2021-06-29 同济大学建筑设计研究院(集团)有限公司 Design method for section of asymmetric flange H-shaped steel combination beam
CN113051754B (en) * 2021-03-23 2022-06-21 同济大学建筑设计研究院(集团)有限公司 Design method for section of asymmetric flange H-shaped steel combination beam

Also Published As

Publication number Publication date
CN110617934B (en) 2021-08-20

Similar Documents

Publication Publication Date Title
CN110617934B (en) Method for measuring torsional wave of flange I-beam with different thicknesses
Nallathambi et al. Design and analysis of MEMS based piezoresistive pressure sensor for sensitivity enhancement
CN103308234B (en) Internal force measuring sensor
Lancaster et al. Paradoxical buckling behaviour of a thin cylindrical shell under axial compression
CN105115690B (en) A kind of multidirectional impedance matrix of vibration isolator and rigidity test experimental rig and test method
CN109141820A (en) Hull model torque and shearing force measurement method
CN109282785B (en) Deformation monitoring method of elastic support plate based on strain monitoring
CN105806203A (en) Three-dimensional relative displacement sensor
CN108106952A (en) A kind of disymmetry section shock loading measuring method of beam
CN106052743A (en) Method for evaluating effects on frequency response functions by transducer quality
CN105352433A (en) Device and method for measuring surface crack depth and shape of hull typical welding structure
CN110108430A (en) A kind of high-precision damage positioning method of fibre reinforced composites beam
CN105737970A (en) Method for testing stress wave propagation law under axial approximate gradient static stress and device thereof
CN111428413B (en) Method for identifying bending rigidity of continuous beam sections
Sayyad et al. Bending of shear deformable plates resting on Winkler foundations according to trigonometric plate theory
CN110617933B (en) Method for measuring impact load of double-symmetrical-section open thin-walled beam
Lauwagie et al. Validation of the Resonalyser method: an inverse method for material identification
CN108195532B (en) Method for measuring equivalent rigidity of beam structure crack
Burada et al. Experimental determinations of some mechanical properties for new types of composite bars with polypropylene honeycomb core
JP2009036774A (en) Stress measuring method and device
Gong et al. Experimental study on the bearing capacity of glass deck under the condition of vehicle traffic
CN111413056B (en) Method for positioning neutral axis of simply supported beam structure with few strain sensors
Saber et al. Experimental Stress Analysis For Woven Carbon, Glass, and Kevlar Laminate Shells
Hong et al. Estimation of distributed rotation angles of steel and concrete beams using fiber optic strain sensors
CN108871631A (en) A kind of frame-type three-component big load strain transducer

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant