CN102721613A - Mechanical property test device for high-intensity bolt at high temperature - Google Patents

Mechanical property test device for high-intensity bolt at high temperature Download PDF

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Publication number
CN102721613A
CN102721613A CN2012102331029A CN201210233102A CN102721613A CN 102721613 A CN102721613 A CN 102721613A CN 2012102331029 A CN2012102331029 A CN 2012102331029A CN 201210233102 A CN201210233102 A CN 201210233102A CN 102721613 A CN102721613 A CN 102721613A
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CN
China
Prior art keywords
anchor clamps
high temperature
bolt
installation sheet
lower clamp
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Pending
Application number
CN2012102331029A
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Chinese (zh)
Inventor
王卫永
王彬
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CHONGQING DAAN HEAVY STEEL STRUCTURE ENGINEERING CO LTD
Chongqing University
Original Assignee
CHONGQING DAAN HEAVY STEEL STRUCTURE ENGINEERING CO LTD
Chongqing University
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.)
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Application filed by CHONGQING DAAN HEAVY STEEL STRUCTURE ENGINEERING CO LTD, Chongqing University filed Critical CHONGQING DAAN HEAVY STEEL STRUCTURE ENGINEERING CO LTD
Priority to CN2012102331029A priority Critical patent/CN102721613A/en
Publication of CN102721613A publication Critical patent/CN102721613A/en
Pending legal-status Critical Current

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Abstract

The invention discloses a mechanical property test device for a high-intensity bolt at a high temperature, jacks are respectively arranged on a left end and a right end of a reaction beam, a screw is arranged on an ejection rod of each jack, the two screws respectively pass through the left end and the right end of a loading beam, adjusting nuts are respectively arranged on the screws, the adjusting nuts are positioned below a bottom end face of the loading beam, a pressure sensor is respectively arranged between each adjusting nut and the loading beam, an upper clamp for fastening an upper end part of a bolt test piece is arranged on the loading beam, a lower clamp for fastening a lower end part of the bolt test piece is arranged on the reaction beam, the upper clamp and the lower clamp are corresponding to each other and are made of fire-resistant steel, an electric furnace with openings on the upper end face and the lower end face is arranged between the reaction beam and the loading beam, the upper clamp passes through the upper end face of the electric furnace and the lower clamp passes through the lower end face of the electric furnace to fasten the bolt test piece in the electric furnace, one end of a pull rope is fixedly arranged on the reaction beam, and the other end of the pull rope is fixedly arranged on the loading beam. According to the test device, the situation of a fire and the high temperature the fire high temperature can be simulated to carry out the mechanical property test on the bolt.

Description

High-strength bolt mechanical behavior under high temperature test unit
Technical field
The present invention relates to a kind of bolt mechanics performance test apparatus, bolt mechanics performance test apparatus under particularly a kind of high temperature.
Background technology
The generation of fire brings great harm for human safety of life and property, is the human disaster that faces jointly, and the life of capturing many people's preciousnesses that it can be merciless can turn to dust and ashes by the wealth with mankind's accumulation in moment.Fire mainly is divided into building fire; Forest fire, industrial and mineral fire, polytypes such as traffic fire; Wherein building fire is the most direct to the mankind's harm; The most serious, because the place that buildings is the mankind depends on for existence and development, and guarantee that personnel and property safety in the buildings build and one of most significant problems that structural design person should consider.
Steel construction is because intensity is high, from heavy and light, builds soon, and advantage such as antidetonation is strong is widely used in building structure, large span especially, and high-rise adopts steel structural form more.The main connected mode of steel building is that high-strength bolt connects, and the fire resistance of connected node is directly connected to the safety of building structure under fire, and the destruction principal mode of high-strength bolt under fire is fail in tension and shear failure.In order better to take precautions against fire steel member connecting portion is protected, thereby guarantee people's safety of life and property need should be understood high-strength bolt mechanical property at high temperature to high-strength bolt various failure modes further investigations at high temperature.
At present; Domestic mechanical property test to high-strength bolt is mainly the Mechanics Performance Testing under the normal temperature; The Mechanics Performance Testing of high-strength bolt behind high-strength bolt Measurement of Material Mechanical Performance and the high temperature, normal temperature down and the Mechanics Performance Testing test unit of the high-strength bolt behind the high temperature simple, need not consider high temperature and aspect problem such as heat insulation; The high-strength bolt Measurement of Material Mechanical Performance is the mechanical property test of bolt steel material, can on the universal testing machine that electric furnace directly is installed, carry out.High-strength bolt test unit under the high temperature need be considered aspects such as hot environment, provision for thermal insulation, grip device, charger and measurement mechanism, and the test unit that is directed against the Mechanics Performance Testing of high-strength bolt under the high temperature is not at present also seen.
Summary of the invention
The object of the invention just provides a kind of high-strength bolt mechanical behavior under high temperature test unit, and it can the simulated fire hot conditions, and the bolt mechanical property is made an experiment.
The objective of the invention is to realize that through such technical scheme it includes surface-based reaction beam, loading beam, lifting jack, goes up anchor clamps and lower clamp, at the left and right two ends of reaction beam a lifting jack is installed respectively; A screw rod all is installed on the push rod of lifting jack, and two screw rods pass the left and right two ends of loading beam respectively, on screw rod, respectively are equipped with one and regulate nut; Regulating nut is positioned at below the loading beam bottom face; Regulate between nut and the loading beam and be provided with a pressure transducer, be equipped with on the loading beam one be used for fixing bolt test specimen upper end on anchor clamps, reaction beam is provided with a lower clamp that is used for fixing bolt test specimen bottom; Upper and lower chucking position is corresponding; Between reaction beam and loading beam, also be provided with the electric furnace of the equal opening of upper and lower end face, last anchor clamps pass the electric furnace upper surface, and lower clamp passes the electric furnace lower surface; The bolt test specimen is fixed in the electric furnace; Said device also includes the stay cord of band displacement meter, and stay cord one end is fixed on the reaction beam, and the other end is fixed on the loading beam.
Further, between adjusting nut and pressure transducer, be provided with pad.
Further, loading beam is provided with the anchor clamps upper connector, and last anchor clamps are installed on the loading beam through the anchor clamps upper connector, and reaction beam is provided with web member under the anchor clamps, and lower clamp is installed on the reaction beam through web member under the anchor clamps.
Further, web member is the brace of band screw under said anchor clamps upper connector and the anchor clamps, and the anchor clamps upper connector is installed between loading beam and the last anchor clamps through bolt, and web member is installed between reaction beam and the lower clamp through bolt under the anchor clamps.
Further; Said upward anchor clamps and lower clamp are the U-shaped installation sheet; The end face of U-shaped installation sheet is provided with the through hole that is used to pass the bolt test specimen; The anchor clamps upper connector is fixed on through latch in the opening of anchor clamps U-shaped installation sheet, and web member is fixed in the lower clamp U-shaped installation sheet opening through latch under the anchor clamps.
Further; Said upward anchor clamps are H shape installation sheet, and the anchor clamps upper connector is fixed on through latch in the open upper end of anchor clamps H shape installation sheet, and said lower clamp includes U-shaped installation sheet and the boss that is arranged on U-shaped installation sheet bottom face; Web member is fixed in the opening of lower clamp U-shaped installation sheet under the anchor clamps through latch; Boss is positioned at the lower ending opening of anchor clamps H shape installation sheet, and the bolt test specimen passes anchor clamps H shape installation sheet and boss, with upper and lower clamps together.
Further, on reaction beam, be fixed with tables are installed, electric furnace is positioned to be installed on the tables.
Further, be provided with thermal insulation board at aperture position place, electric furnace upper surface and lower surface aperture position place.
Further, said thermal insulation board is the alumina silicate thermal insulation board.
Owing to adopted technique scheme, the present invention to have following advantage:
The present invention provides well behaved test unit for high-strength bolt Mechanics Performance Testing at high temperature; Satisfied and tested required intensification, constant temperature, anchor clamps are installed, load measurement; Testing requirements such as displacement measurement and loading; Real simulated the hot environment of fire, test specimen Mechanics Performance Testing at high temperature can successfully be accomplished, thereby the anti-fire design that connects fire resistance and instruct the steel member to connect for research building iron member high-strength bolt is laid a good foundation.
Other advantages of the present invention, target and characteristic will be set forth in instructions subsequently to a certain extent; And to a certain extent; Based on being conspicuous to those skilled in the art, perhaps can from practice of the present invention, obtain instruction to investigating of hereinafter.Target of the present invention and other advantages can realize and obtain through following instructions and claims.
Description of drawings
Description of drawings of the present invention is following.
Fig. 1 is the structural representation of first kind of embodiment of the present invention;
Fig. 2 is the structural representation of second kind of embodiment of the present invention;
Fig. 3 is the structural representation of upper and lower anchor clamps among Fig. 1;
Fig. 4 is the left view of Fig. 3;
Fig. 5 is the structural representation of upper and lower anchor clamps among Fig. 2;
Fig. 6 is the left view of Fig. 5.
Among the figure: 1. reaction beam; 2. loading beam; 3. lifting jack; 4. go up anchor clamps; 5. lower clamp; 6. screw rod; 7. adjusting nut; 8. pressure transducer; 9. bolt test specimen; 10. electric furnace; 11. pad; 12. anchor clamps upper connector; 13. web member under the anchor clamps; 14. boss; 15. tables are installed; 16. displacement meter; 17. stay cord; 18. thermal insulation board.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is described further.
High-strength bolt mechanical behavior under high temperature test unit, said device include surface-based reaction beam 1, loading beam 2, lifting jack 3, go up anchor clamps 4 and lower clamp 5, at the left and right two ends of reaction beam 1 lifting jack 3 are installed respectively; The left and right two ends that 6, two screw rods 6 of a screw rod pass loading beam 2 respectively all are installed on the push rod of lifting jack 3, on screw rod 6, respectively are equipped with one and regulate nut 7; Regulating nut 7 is positioned at below loading beam 2 bottom faces; Regulate between nut 7 and the loading beam 2 and be provided with a pressure transducer 8, be equipped with on the loading beam 2 one be used for fixing bolt test specimen 9 upper ends on anchor clamps 4, reaction beam 1 is provided with a lower clamp 5 that is used for fixing bolt test specimen 9 bottoms; Upper and lower anchor clamps 4,5 positions are corresponding and be fire-resistant steel; Between reaction beam 1 and loading beam 2, also be provided with the electric furnace 10 of the equal opening of upper and lower end face, last anchor clamps 4 pass electric furnace 10 upper surfaces, and lower clamp 5 passes electric furnace 10 lower surfaces; Bolt test specimen 9 is fixed in the electric furnace 10; Said device also includes the stay cord 17 of band displacement meter 16, and stay cord 17 1 ends are fixed on the reaction beam 1, and the other end is fixed on the loading beam 2.
During installation, reaction beam 1 is fixed on the groove on testing laboratory ground, screw rod 6 is fixed on the push rod of lifting jack 3; Install adjustment nut 7 on screw rod 6 regulating placement force sensor 8 on the nut 7, lifts loading beam 2 on pressure transducer 8 again; On loading beam 2, install anchor clamps 4; Lower clamp 5 is installed on reaction beam 1, and bolt test specimen 9 is fixed on upper and lower anchor clamps 4, between 5, again electric furnace 10 is installed in bolt test specimen 9 positions.After treating 9 installations of bolt test specimen,, start electric furnace 10 power switches through electric furnace 10 preset target temperature values; Treat to protect constant temperature 30 minutes after temperature reaches predetermined value; Start lifting jack 3, read the load that bolt test specimen 9 bears, treat to stop lifting jack 3 after test specimen is broken or cut off through pressure transducer 8; The reading of record pressure transducer 8 this moment, the maximal value of reading is the maximum, force that bolt test specimen 9 can bear under the condition of high temperature.Through reading displacement meter 16 and pressure transducer 8, can measure the variation relation of bolt test specimen 9 in a certain temperature lower stress and deformation.The present invention provides well behaved test unit for high-strength bolt Mechanics Performance Testing at high temperature; Satisfied and tested required intensification, constant temperature, anchor clamps are installed, load measurement; Testing requirements such as displacement measurement and loading; Real simulated the hot environment of fire, test specimen Mechanics Performance Testing at high temperature can successfully be accomplished, thereby the anti-fire design that connects fire resistance and instruct the steel member to connect for research building iron member high-strength bolt is laid a good foundation.
In order to make pressure transducer 8 stressed even, accuracy of reading is provided with pad 11 between adjusting nut 7 and pressure transducer 8.
For the ease of install, lower clamp 4,5; Loading beam 2 is provided with anchor clamps upper connector 12; Last anchor clamps 4 are installed on the loading beam 2 through anchor clamps upper connector 12, and reaction beam 1 is provided with web member 13 under the anchor clamps, and lower clamp 5 is installed on the reaction beam 1 through web member under the anchor clamps 13.
Web member 13 is the brace of band screw under said anchor clamps upper connector 12 and the anchor clamps, and the anchor clamps upper connector is installed between loading beam 2 and the last anchor clamps 4 through bolt, and web member 13 is installed between reaction beam 1 and the lower clamp 5 through bolt under the anchor clamps.
The said anchor clamps 4 of going up are the U-shaped installation sheet with lower clamp 5; The end face of U-shaped installation sheet is provided with the through hole that is used to pass bolt test specimen 9; Anchor clamps upper connector 12 is fixed on through latch in the opening of U-shaped installation sheet of anchor clamps 4, and web member 13 is fixed in the U-shaped installation sheet opening of lower clamp 5 through latch under the anchor clamps.During test, bolt test specimen 9 bears upper and lower pulling force, can test out the maximum pull that the bolt test specimen can bear.
Said upward anchor clamps 4 are H shape installation sheet; Anchor clamps upper connector 12 is fixed on through latch in the open upper end of H shape installation sheet of anchor clamps 4; Said lower clamp 5 includes U-shaped installation sheet and the boss 14 that is arranged on U-shaped installation sheet bottom face; Web member 13 is fixed on through latch in the opening of U-shaped installation sheet of lower clamp 5 under the anchor clamps; Boss 14 is positioned at the lower ending opening of the H shape installation sheet of anchor clamps 4, and bolt test specimen 9 passes the H shape installation sheet and the boss 14 of anchor clamps 4, and upper and lower anchor clamps 4,5 are fixed together.During test, bolt test specimen 9 holds shearing, can test out the maximum transversal shearing that bolt test specimen 9 can bear.
For the ease of electric furnace 10 is installed, on reaction beam 1, be fixed with tables 15 are installed, electric furnace 10 is positioned to be installed on the tables 15.
In order to prevent to damage the present invention, be provided with thermal insulation board 18 at electric furnace aperture position place, 10 upper surface and lower surface aperture position place because of the High temperature diffusion that electric furnace 10 produces.
Said thermal insulation board 18 is the alumina silicate thermal insulation board.
Explanation is at last; Above embodiment is only unrestricted in order to technical scheme of the present invention to be described; Although with reference to preferred embodiment the present invention is specified, those of ordinary skill in the art should be appreciated that and can make amendment or be equal to replacement technical scheme of the present invention; And not breaking away from the aim and the scope of present technique scheme, it all should be encompassed in the middle of the claim scope of the present invention.

Claims (9)

1. high-strength bolt mechanical behavior under high temperature test unit is characterized in that: said device includes surface-based reaction beam, loading beam, lifting jack, goes up anchor clamps and lower clamp, at the left and right two ends of reaction beam a lifting jack is installed respectively; A screw rod all is installed on the push rod of lifting jack, and two screw rods pass the left and right two ends of loading beam respectively, on screw rod, respectively are equipped with one and regulate nut; Regulating nut is positioned at below the loading beam bottom face; Regulate between nut and the loading beam and be provided with a pressure transducer, be equipped with on the loading beam one be used for fixing bolt test specimen upper end on anchor clamps, reaction beam is provided with a lower clamp that is used for fixing bolt test specimen bottom; Upper and lower chucking position is corresponding; Between reaction beam and loading beam, also be provided with the electric furnace of the equal opening of upper and lower end face, last anchor clamps pass the electric furnace upper surface, and lower clamp passes the electric furnace lower surface; The bolt test specimen is fixed in the electric furnace; Said device also includes the stay cord of band displacement meter, and stay cord one end is fixed on the reaction beam, and the other end is fixed on the loading beam.
2. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 1 is characterized in that: between adjusting nut and pressure transducer, be provided with pad.
3. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 1; It is characterized in that: loading beam is provided with the anchor clamps upper connector; Last anchor clamps are installed on the loading beam through the anchor clamps upper connector; Reaction beam is provided with web member under the anchor clamps, and lower clamp is installed on the reaction beam through web member under the anchor clamps.
4. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 3; It is characterized in that: web member is the brace of band screw under said anchor clamps upper connector and the anchor clamps; The anchor clamps upper connector is installed between loading beam and the last anchor clamps through bolt, and web member is installed between reaction beam and the lower clamp through bolt under the anchor clamps.
5. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 4; It is characterized in that: said upward anchor clamps and lower clamp are the U-shaped installation sheet; The end face of U-shaped installation sheet is provided with the through hole that is used to pass the bolt test specimen; The anchor clamps upper connector is fixed on through latch in the opening of anchor clamps U-shaped installation sheet, and web member is fixed in the lower clamp U-shaped installation sheet opening through latch under the anchor clamps.
6. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 4; It is characterized in that: said upward anchor clamps are H shape installation sheet; The anchor clamps upper connector is fixed in the open upper end of anchor clamps H shape installation sheet through latch; Said lower clamp includes U-shaped installation sheet and the boss that is arranged on U-shaped installation sheet bottom face, and web member is fixed on through latch in the opening of lower clamp U-shaped installation sheet under the anchor clamps, and boss is positioned at the lower ending opening of anchor clamps H shape installation sheet; The bolt test specimen passes anchor clamps H shape installation sheet and boss, with upper and lower clamps together.
7. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 1 is characterized in that: on reaction beam, be fixed with tables are installed, electric furnace is positioned to be installed on the tables.
8. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 1 is characterized in that: be provided with thermal insulation board at aperture position place, electric furnace upper surface and lower surface aperture position place.
9. high-strength bolt mechanical behavior under high temperature test unit as claimed in claim 8, its characteristic ground in: said thermal insulation board is the alumina silicate thermal insulation board.
CN2012102331029A 2012-07-06 2012-07-06 Mechanical property test device for high-intensity bolt at high temperature Pending CN102721613A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2012102331029A CN102721613A (en) 2012-07-06 2012-07-06 Mechanical property test device for high-intensity bolt at high temperature

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2012102331029A CN102721613A (en) 2012-07-06 2012-07-06 Mechanical property test device for high-intensity bolt at high temperature

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CN102721613A true CN102721613A (en) 2012-10-10

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105806701A (en) * 2016-03-17 2016-07-27 西北工业大学 High-temperature fatigue test clamp device for pretension bolt
CN105891006A (en) * 2016-06-20 2016-08-24 国网内蒙古东部电力有限公司经济技术研究院 Low-temperature tension test device of bolt connection joint
CN109765042A (en) * 2019-01-24 2019-05-17 郑州大学 A kind of multi-functional tapping screw drawing test clamp
CN112763312A (en) * 2020-12-29 2021-05-07 中国航空工业集团公司西安飞机设计研究所 Tension-shear composite bolt fatigue test clamp and method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201152840Y (en) * 2007-12-19 2008-11-19 奇瑞汽车股份有限公司 General bolt/nut test clamp
CN101413938A (en) * 2008-11-28 2009-04-22 哈尔滨工业大学 Anti-fire test device of restrained column
CN102507319A (en) * 2011-10-21 2012-06-20 奇瑞汽车股份有限公司 Bolt fatigue test device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201152840Y (en) * 2007-12-19 2008-11-19 奇瑞汽车股份有限公司 General bolt/nut test clamp
CN101413938A (en) * 2008-11-28 2009-04-22 哈尔滨工业大学 Anti-fire test device of restrained column
CN102507319A (en) * 2011-10-21 2012-06-20 奇瑞汽车股份有限公司 Bolt fatigue test device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
黄勇祥: "高温下钢结构高强度螺栓连接极限承载力的研究", 《中国优秀硕士学位论文全文数据库工程科技II辑》, 15 March 2005 (2005-03-15), pages 30 - 34 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105806701A (en) * 2016-03-17 2016-07-27 西北工业大学 High-temperature fatigue test clamp device for pretension bolt
CN105806701B (en) * 2016-03-17 2018-06-05 西北工业大学 A kind of pretension bolt high temperature fatigue test clamp device
CN105891006A (en) * 2016-06-20 2016-08-24 国网内蒙古东部电力有限公司经济技术研究院 Low-temperature tension test device of bolt connection joint
CN109765042A (en) * 2019-01-24 2019-05-17 郑州大学 A kind of multi-functional tapping screw drawing test clamp
CN112763312A (en) * 2020-12-29 2021-05-07 中国航空工业集团公司西安飞机设计研究所 Tension-shear composite bolt fatigue test clamp and method

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Application publication date: 20121010