CN207215329U - A kind of miniature steel pipe pile pile stress test device - Google Patents
A kind of miniature steel pipe pile pile stress test device Download PDFInfo
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- CN207215329U CN207215329U CN201721305729.5U CN201721305729U CN207215329U CN 207215329 U CN207215329 U CN 207215329U CN 201721305729 U CN201721305729 U CN 201721305729U CN 207215329 U CN207215329 U CN 207215329U
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Abstract
The utility model belongs to rock-soil engineering in-situ technical field of test equipment, more particularly to a kind of miniature steel pipe pile stress test device, and it is pointed that the stake end of miniature steel pipe pile is welded into closing；Sensor mounting hole pore-forming in a manner of gas flame cuttiug; there is grip block at temperature self-compensation type mini optical fibre grating strain transducer both ends; grip block is welded on miniature steel pipe pile, and the optical fiber of optical fiber and extraction bottom surface between each temperature self-compensation type mini optical fibre grating strain sensing is protected with sheathed wire；Sensor mounting hole on miniature steel pipe pile surface and is completely covered by by hole excision plate weld, the end of a thread of temperature self-compensation type mini optical fibre grating strain transducer string is drawn by fairlead and is connected with optical fiber grating sensing analyzer, optical fiber grating sensing analyzer is connected with data storage computer, its constructional device is simple, and measurement accuracy is high, high sensitivity, error is small, anti-electromagnetic field interference performance is strong, and survival rate is high, it is easy to accomplish quasi-distributed and automatic monitoring.
Description
Technical field：
The utility model belongs to rock-soil engineering in-situ technical field of test equipment, more particularly to a kind of foundation ditch or slope retaining
Middle miniature steel pipe pile stress test device, make up and improve the deficiency of current test device and method of testing, by along miniature
Steel-pipe pile pile body, which buries self-compensation type mini optical fibre grating strain transducer string, more accurately to draw miniature steel pipe pile in water and soil
The pile body bending stress regularity of distribution under pressure effect, certain ginseng is provided for later more in-depth study and Practical Project
Examine value.
Background technology：
Mini pile is a kind of Small Diameter Pile to be grown up based on root pile, and stake footpath is generally 90~300mm.It is and micro-
Shaped steel pile tube refers to use a kind of mini pile of the steel pipe as intensive aspect.Because miniature steel pipe pile has, ground adaptability is strong, holds
Load power is high, arrangement form is more flexible, construction occupied ground is small, in light weight, pore-forming is fast, construction machinery is minimized and can surpassed
Many advantages, such as preceding supporting, it is used widely in recent years in the engineering such as pattern foundation pit supporting structure and slope reinforcement, particularly in Tu Yan
Coordinate anchor pole (rope) to use in compound stratum, form a kind of New Supporting pattern.In Excavation Process, miniature steel pipe pile exists
Water And Earth Pressures effect under occur bending and deformation, larger bending stress will be produced, for effectively checking miniature steel pipe pile by masterpiece
With, guarantee construction safety and construction quality, and provide data for design, it is necessary to miniature steel pipe pile in Excavation Process
Bending stress is monitored in real time, it is ensured that steel-pipe pile stress meets safety requirements.Traditional electric detecting technology is mostly using in pile body
The method that outer wall pastes foil gauge, test result is protected from environmental larger, and actual loading result exists certain with test result
Error, and the survival rate of disturbing influence foil gauge mechanical in by site operation vibrations and digging process is not high, causes to test number
According to missing.Fiber grating sensing technology is accompanied by the development of Fibre Optical Communication Technology and fibre optics and a kind of caused new light
Electronics technologies, fiber Bragg grating strain sensor can be sensed extraneous trickle strain by the movement of bragg reflection wavelength and become
Change, be a kind of sensing element of function admirable so as to realize on-line measurement structural stress, compared with traditional electric detecting technology, tool
There are good stability, corrosion-resistant, electromagnetism interference, quasi- distribution measuring, small volume, simple in construction, precision is high, can be supervised in real time
The features such as survey.Because optical fiber is very thin and weak, careful installation, Fibre Optical Sensor prison in situ must be carried out to sensor and Transmission Fibers
How at the scene the key for surveying success or failure is realizing the embedded positioning of sensor in construction environment and is ensureing its survival rate.It is Chinese special
Profit 201320628409.9 discloses a kind of static pressure high-strength prestressed concrete pipe pile pile stress test device, high-strength prestressed
Concrete tubular pile internal cutting is formed with shallow slot, optical fiber Bragg grating sensor and armored optical cable and connected by quasi-distributed welding, series connection
Optical fiber Bragg grating sensor and armored optical cable implantation high-strength prestressed concrete pipe pile shallow slot in and mixed with epoxy resin
Close liquid and be packaged protection, optical fiber Bragg grating sensor is tested as needed in the position of high-strength prestressed concrete pipe pile
Soil layer absolute altitude laid；The inside top of high-strength prestressed concrete pipe pile, which is opened, is formed with pile body drilling, and armored optical cable passes through
Pile body drilling is drawn to be connected with data collecting system；Its apparatus structure is simple, easy to operate, and measurement accuracy is high, high sensitivity, resists
Interference of electromagnetic field ability is strong, and survival rate is high, quasi-distributed and automatic monitoring is easily achieved compared with traditional load-sensing unit, still
The test device is mainly for the PHC piles in soft stratum, embedding optical fibre Bragg grating sensing
Device string once has a failure to cause large effect to test process, or even sensor string can be caused all to fail；In addition
Pile body fluting can affect to the intensity of stake, furthermore fail to reject the pile strain as caused by temperature in test process
Change is so that influence the accuracy of test result.
The content of the invention：
The shortcomings that goal of the invention of the present utility model is to overcome prior art to exist, seeking one kind can accurately, in real time
The device of miniature steel pipe pile pile body stress is measured, when self-compensation type mini optical fibre grating strain transducer under tension or pressure
During effect, the elongation or compression of sensor make the fiber grating cycle change, and then change fiber Bragg grating strain sensor
Effective refractive index, so as to obtain bending stress distribution of the miniature steel pipe pile under Water And Earth Pressures effect.
To achieve these goals, the agent structure bag of miniature steel pipe pile pile stress test device described in the utility model
Include miniature steel pipe pile, temperature self-compensation type mini optical fibre grating strain transducer string, sheathed wire, optical fiber grating sensing analysis
Instrument, data storage computer, sensor mounting hole, hole excision plate and fairlead；Miniature steel pipe pile uses the city commonly used in engineering
The steel pipe sold, it is pointed that stake end is welded into closing；Sensor mounting hole is in a manner of gas flame cuttiug in miniature steel pipe pile pore-forming, sensing
Device mounting hole is 4cm × 7cm square-section, and its long side is consistent with the axis direction of miniature steel pipe pile, sensor mounting hole
Centre of form section overlaps with the centre of form section of each temperature self-compensation type mini optical fibre grating strain transducer；Temperature self-compensation type
Mini optical fibre grating strain transducer string is connected by temperature self-compensation type mini optical fibre grating strain transducer according to design requirement
Into quasi-distributed sensor string, temperature self-compensation type mini optical fibre grating strain transducer string is arranged in micro- in a welding manner
The inner surface of shaped steel pile tube, the number of temperature self-compensation type mini optical fibre grating strain transducer is according to determination is actually needed, often
There is grip block at individual temperature self-compensation type mini optical fibre grating strain transducer both ends, and grip block is welded on miniature steel pipe pile, its
In optical fiber between each temperature self-compensation type mini optical fibre grating strain sensing and draw the optical fiber of bottom surface and all led with armouring
Line is protected；Sensor mounting hole on miniature steel pipe pile surface and is completely covered by by hole excision plate weld, and temperature self-compensation declines
The end of a thread of type fiber Bragg grating strain sensor string is drawn by the fairlead at the top of miniature steel pipe pile and divided with optical fiber grating sensing
Analyzer is connected, and optical fiber grating sensing analyzer is connected with data storage computer, during whole Installation And Test, it is ensured that armouring
The bending angle of wire is not more than 90 degree, in order to avoid optical fiber fractures, temperature self-compensation type fiber Bragg grating strain sensor can be automatic
Reject influence of the temperature change to test result.
The utility model complete stress test specific embodiment be：
(1) according to the design requirement of miniature steel pipe pile section to be measured, determine that temperature self-compensation type mini optical fibre grating should
Become the spacing of each sensor in sensor string, temperature self-compensation type mini optical fibre grating strain transducer is connected into quasi-distributed
Temperature self-compensation type mini optical fibre grating strain transducer string, between each temperature self-compensation type mini optical fibre grating strain sensing
Optical fiber and draw bottom surface optical fiber all protected with sheathed wire；
(2) temperature self-compensation type mini optical fibre grating strain transducer string first connects light before miniature steel pipe pile installation
Fine grating sensing analyzer and data storage computer, on the one hand check whether optical fiber fractures, on the other hand examine temperature self-compensation
Whether the type fiber Bragg grating strain sensor of declining fails；
(3) installation site according to temperature self-compensation type mini optical fibre grating strain transducer string in miniature steel pipe pile,
Position and the size of sensor mounting hole are drawn with chalk in miniature steel pipe pile outer wall, in miniature steel pipe in a manner of gas flame cuttiug
Stake pore-forming, the centre of form section of sensor mounting hole are tried one's best and each temperature self-compensation type mini optical fibre grating strain transducer
Centre of form section is overlapped, and after miniature steel pipe pile cooling, the miniature light of temperature self-compensation type is installed to miniature steel pipe pile inwall with sand paper
Polished the position of fiber grating strain transducer string；
(4) by two string temperature self-compensation type mini optical fibre grating sensor strings from the end of miniature steel pipe pile along enter miniature steel
The inside of pile tube, two string temperature self-compensation type mini optical fibre grating strain transducer strings are symmetrically welded by sensor mounting hole
In the inwall of miniature steel pipe pile, optical fiber grating sensing analyzer and data storage computer are connected after the completion of welding, examines temperature certainly
The survival rate of compensation fiber Bragg grating strain sensor string makes it to be less than 90%, if temperature self-compensation type fiber grating strain
The survival rate of sensor string is less than 90%, it is necessary to the sensor for removing damage is reinstalled, and cuts hole after having inspected
Except sensor mounting hole is completely covered by miniature steel pipe pile surface by plate weld, it is ensured that weldquality, temperature self-compensation type are miniature
Fiber Bragg grating strain sensor string the end of a thread (each temperature self-compensation type mini optical fibre grating strain transducer string the end of a thread, one
Damaged on end can badly be tested by the other end) drawn by the fairlead at the top of miniature steel pipe pile；
(5) construction part of miniature steel pipe pile is determined on construction ground, and using down-the-hole pore-forming, borehole cleaning, aperture is slightly larger than micro-
The diameter of shaped steel pile tube；Miniature steel pipe pile with temperature self-compensation type mini optical fibre grating strain transducer string is put into and is drilled
Hole in, it is ensured that wherein a string of temperature self-compensation type mini optical fibre grating strain transducer displacements are another in excavation of foundation pit face
Displacement is in facing native face, if miniature steel pipe pile can not lean on its deadweight to be put into drilling, using Miniature digging machine by miniature steel pipe pile gently
Predetermined absolute altitude is squeezed into, it is noted that protection temperature self-compensation type mini optical fibre grating strain passes in miniature steel pipe pile work progress
Sensor string and the ring flange of sheathed wire termination；
(6) Grouting Pipe is inserted to the bottom of miniature steel pipe pile, the cement mortar mixed slowly injected by slip casting machine miniature
In steel-pipe pile, the ratio of mud of cement mortar is strict controlled in 0.45~0.5, to pay attention to the pressure in Grouting Pipe during slip casting the moment
Table, it is ensured that grouting pressure reaches 0.5MPa, and Grouting Pipe wouldn't be pulled out after slip casting, until cement mortar flows out outside miniature steel pipe pile and is
Only, Grouting Pipe is extracted, sealed steel pipe end, is pressurizeed 5 minutes, untill treating that cement mortar flows out outside steel pipe again, if once grouting
Be difficult to meet set rushing be full of coefficient requirement, it is necessary to repeatedly gap slip casting, until untill the frost boiling of miniature steel pipe pile stake top, then
Grouting Pipe is extracted, completes slip casting operation, the ring flange of sheathed wire termination is ensured during slip casting slurries entrance；
(7) by temperature self-compensation type fiber Bragg grating strain sensor string, optical fiber grating sensing analyzer and data storage electricity
Brain is connected, the survival rate of detection temperature self-compensation type mini optical fibre grating strain transducer string；
(8) before excavation of foundation pit, the cement mortar in the miniature steel pipe pile after slip casting conserves 28 days or the resistance to compression of cement mortar
After intensity reaches the 75% of design strength, temperature self-compensation type fiber Bragg grating strain sensor string, optical fiber grating sensing are analyzed
Instrument and data storage computer are connected, and check whether test device connection is intact, and record temperature self-compensation type fiber grating strain
Sensor string initial wavelength；
(9) in Excavation Process, it is self-complementary that temperature is recorded in real time with optical fiber grating sensing analyzer and data storage computer
The wavelength for the type fiber-optic grating sensor string that declines is repaid, the to be measured of miniature steel pipe pile can be tried to achieve using formula (1), (2), (3)
The pile body bending stress of section,
Δεx=Δ λε/Kε (1)
σi=EsΔεx (2)
Mi=σiW (3)
Wherein Δ εxFor the axial strain variable quantity of miniature steel pipe pile；ΔλεCentered on wavelength variable quantity, unit nm；KεFor
Strain transducer sensitivity coefficient；σiFor the bending stress at any test section mini steel-pipe pile axis, its numerical value is equal to foundation ditch
Face the half in native face and excavation face stress difference, units MPa；EsFor the modulus of elasticity of miniature steel pipe pile, units MPa；MiTo be any
Test the moment of flexure of section mini steel-pipe pile, unit kNm；W be miniature steel pipe pile bending sections coefficient, unit mm3；For peace
Full consideration, formula (3) do not consider increase effect of the slip casting to bending rigidity in miniature steel pipe pile in calculated bending moment；If
The increase effect of miniature steel pipe pile bending rigidity, can be multiplied by 1.2~1.5 by the rigidity of non-slip casting miniature steel pipe pile after consideration slip casting
Enhancement coefficient.
For the utility model compared with existing measuring technology, its constructional device is simple, and measurement accuracy is high, high sensitivity, error
Small, anti-electromagnetic field interference performance is strong, and survival rate is high, and quasi-distributed and automation prison is easily achieved compared with traditional test element
Survey.
Brief description of the drawings：
Fig. 1 is the agent structure principle schematic of miniature steel pipe pile pile stress test device described in the utility model.
Fig. 2 is miniature steel pipe pile perforate schematic diagram described in the utility model.
Fig. 3 is the plan structure of temperature self-compensation type mini optical fibre grating strain transducer string described in the utility model installation
Schematic diagram.
Fig. 4 is miniature steel pipe pile bending distribution map (one) described in the utility model embodiment.
Fig. 5 is miniature steel pipe pile bending distribution map (two) described in the utility model embodiment.
Embodiment：
The utility model is described in further detail by way of example and in conjunction with the accompanying drawings.
Embodiment：
The agent structure of miniature steel pipe pile pile stress test device described in the present embodiment includes miniature steel pipe pile 1, temperature
Self-compensation type mini optical fibre grating strain transducer string 2, sheathed wire 3, optical fiber grating sensing analyzer 4, data storage computer
5th, sensor mounting hole 6, hole excision plate 7 and fairlead 8；Miniature steel pipe pile 1 is using the commercially available steel pipe commonly used in engineering, stake
It is pointed that end is welded into closing；Sensor mounting hole 6 is in a manner of gas flame cuttiug in the pore-forming of miniature steel pipe pile 1, sensor mounting hole 6
For 4cm × 7cm square-section, its long side is consistent with the axis direction of miniature steel pipe pile 1, and the centre of form of sensor mounting hole 6 is cut
Face overlaps with the centre of form section of each temperature self-compensation type mini optical fibre grating strain transducer；The miniature light of temperature self-compensation type
The standard that fiber grating strain transducer string 2 is connected into by temperature self-compensation type mini optical fibre grating strain transducer according to design requirement
Distributed sensor string, temperature self-compensation type mini optical fibre grating strain transducer string 2 are arranged in miniature steel in a welding manner
The inner surface of pile tube 1, the number of temperature self-compensation type mini optical fibre grating strain transducer determined according to being actually needed, Mei Gewen
There is grip block at degree self-compensation type mini optical fibre grating strain transducer both ends, and grip block is welded on miniature steel pipe pile 1, wherein respectively
The optical fiber of optical fiber and extraction bottom surface between temperature self-compensation type mini optical fibre grating strain sensing is all protected with sheathed wire 3
Shield；Hole excision plate 7 is welded on the surface of miniature steel pipe pile 1 and is completely covered by sensor mounting hole 6, and temperature self-compensation type is miniature
The end of a thread of fiber Bragg grating strain sensor string 2 is drawn by the fairlead 8 at the top of miniature steel pipe pile 1 and divided with optical fiber grating sensing
Analyzer 4 is connected, and optical fiber grating sensing analyzer 4 is connected with data storage computer 5, during whole Installation And Test, it is ensured that
The bending angle of sheathed wire 3 is not more than 90 degree, in order to avoid optical fiber fractures, temperature self-compensation type fiber Bragg grating strain sensor can
Influence of the automatic rejection temperature change to test result.
The present embodiment complete stress test specific embodiment be：
(1) according to the design requirement of 1 section to be measured of miniature steel pipe pile, determine that temperature self-compensation type mini optical fibre grating should
Become the spacing of each sensor in sensor string 2, temperature self-compensation type mini optical fibre grating strain transducer is connected into quasi- distribution
The temperature self-compensation type mini optical fibre grating strain transducer string 2 of formula, each temperature self-compensation type mini optical fibre grating strain sensing
Between optical fiber and draw bottom surface optical fiber all protected with sheathed wire 3；
(2) temperature self-compensation type mini optical fibre grating strain transducer string 2 is first connected before the installation of miniature steel pipe pile 1
Optical fiber grating sensing analyzer 4 and data storage computer 5, on the one hand check whether optical fiber fractures, on the other hand examine temperature certainly
Whether compensation mini optical fibre grating strain transducer fails；
(3) according to 2 installation position in miniature steel pipe pile 1 of temperature self-compensation type mini optical fibre grating strain transducer string
Put, position and the size of sensor mounting hole 6 are drawn with chalk in the outer wall of miniature steel pipe pile 1, micro- in a manner of gas flame cuttiug
The pore-forming of shaped steel pile tube 1, the centre of form section of sensor mounting hole 6 are tried one's best and each temperature self-compensation type mini optical fibre grating strain
The centre of form section of sensor overlaps, and after the cooling of miniature steel pipe pile 1, it is self-complementary to install temperature to the inwall of miniature steel pipe pile 1 with sand paper
Polished the position for repaying the type fiber Bragg grating strain sensor string 2 that declines；
(4) it is two string temperature self-compensation type mini optical fibre grating sensor strings 2 are miniature along entering from the end of miniature steel pipe pile 1
The inside of steel-pipe pile 1, it is by sensor mounting hole 6 that two string temperature self-compensation type mini optical fibre grating strain transducer strings 2 are right
Claim the inwall for being welded on miniature steel pipe pile 1, optical fiber grating sensing analyzer 4 and data storage computer 5, inspection are connected after the completion of welding
The survival rate (survival rate must not be less than 90%) of temperature self-compensation type fiber Bragg grating strain sensor string 2 is tested, if temperature self-compensation
The survival rate of formula fiber Bragg grating strain sensor string 2 is less than 90%, it is necessary to the sensor for removing damage is reinstalled, and examines
After the completion of hole excision plate 7 is welded on the surface of miniature steel pipe pile 1 and is completely covered by sensor mounting hole 6, it is ensured that weldquality,
The end of a thread (each temperature self-compensation type mini optical fibre grating strain of temperature self-compensation type mini optical fibre grating strain transducer string 2
2 the end of a thread of sensor string, one end damage can be tested by the other end) drawn by the fairlead 8 at the top of miniature steel pipe pile 1；
(5) construction part of miniature steel pipe pile 1 is determined on construction ground, and using down-the-hole pore-forming, borehole cleaning, aperture is slightly larger than micro-
The diameter of shaped steel pile tube 1；Miniature steel pipe pile 1 with temperature self-compensation type mini optical fibre grating strain transducer string 2 is put into
In the hole being drilled, it is ensured that wherein a string of temperature self-compensation type mini optical fibre grating strain transducer strings 2 are located at excavation of foundation pit face,
Another displacement is in facing native face, if miniature steel pipe pile 1 can not lean on its deadweight to be put into drilling, using Miniature digging machine by miniature steel pipe pile
1 gently squeezes into predetermined absolute altitude, it is noted that protection temperature self-compensation type mini optical fibre grating in the work progress of miniature steel pipe pile 1
Strain transducer string 2 and the ring flange of the termination of sheathed wire 3；
(6) Grouting Pipe is inserted to the bottom of miniature steel pipe pile 1, the cement mortar mixed slowly injected by slip casting machine miniature
In steel-pipe pile 1, the ratio of mud of cement mortar is strict controlled in 0.45~0.5, to pay attention to the pressure in Grouting Pipe during slip casting the moment
Power table, it is ensured that grouting pressure reaches 0.5MPa, and Grouting Pipe wouldn't be pulled out after slip casting, until cement mortar flows out outside miniature steel pipe pile 1
Untill, Grouting Pipe is extracted, sealed steel pipe end, is pressurizeed 5 minutes, untill treating that cement mortar flows out outside steel pipe again, ordinary circumstance,
Once grouting be difficult to meet set rushing be full of coefficient requirement, it is necessary to repeatedly gap slip casting, until the stake top of miniature steel pipe pile 1 is bursted and become muddy when a thaw sets in
Untill, Grouting Pipe is then extracted, completes slip casting operation, the ring flange of the termination of sheathed wire 3 is ensured during slip casting not have
Slurries enter；
(7) by temperature self-compensation type fiber Bragg grating strain sensor string 2, optical fiber grating sensing analyzer 4 and data storage
Computer 5 is connected, the survival rate of detection temperature self-compensation type mini optical fibre grating strain transducer string 2；
(8) before excavation of foundation pit, the cement mortar in the miniature steel pipe pile 1 after slip casting conserves 28 days or the resistance to compression of cement mortar
After intensity reaches the 75% of design strength, temperature self-compensation type fiber Bragg grating strain sensor string 2, optical fiber grating sensing are analyzed
Instrument 4 and data storage computer 5 are connected, and check whether test device connection is intact, and record temperature self-compensation type fiber grating and answer
Become the initial wavelength of sensor string 2；
(9) in Excavation Process, temperature is recorded in real time certainly with optical fiber grating sensing analyzer 4 and data storage computer 5
The wavelength of compensation mini optical fibre grating sensor string 2, miniature steel pipe pile 1 can be tried to achieve using formula (1), (2), (3)
The pile body bending stress of section to be measured,
Δεx=Δ λε/Kε (1)
σi=EsΔεx (2)
Mi=σiW (3)
Wherein Δ εxFor the axial strain variable quantity of miniature steel pipe pile；ΔλεCentered on wavelength variable quantity, unit (nm)；Kε
For strain transducer sensitivity coefficient；σiFor the bending stress at any test section mini steel-pipe pile axis, its numerical value is equal to base
Native face and the half of excavation face stress difference, unit (MPa) are faced in hole；EsFor the modulus of elasticity of miniature steel pipe pile, unit (MPa)；Mi
For the moment of flexure of any test section mini steel-pipe pile, unit (kNm)；W is the bending sections coefficient of miniature steel pipe pile, can be tabled look-up
Obtain, unit (mm3)；For the purpose of safety, formula (3) does not consider that slip casting resists in miniature steel pipe pile in calculated bending moment
The increase effect of curved rigidity；, will non-slip casting miniature steel pipe if considering the increase effect of miniature steel pipe pile bending rigidity after slip casting
The rigidity of stake is multiplied by 1.2~1.5 enhancement coefficient.
The present embodiment carries out structure such as Fig. 1 and as indicated with 2 of stress test to miniature steel pipe pile, as can be seen from Fig.,
In Excavation Process, main bearing member of the miniature steel pipe pile as supporting construction, the load born is larger, is opened in foundation ditch
The moment dug to steel-pipe pile top during substrate is maximum, and maximum respectively may be about 3.83kNm, 3.61kNm；Miniature steel pipe pile
Moment middle and upper part change greatly, bottom change it is smaller, maximal bending moment changing value appears in the top of steel-pipe pile, respectively may be about
5.15kN·m、4.42kN·m。
Claims (1)
1. a kind of miniature steel pipe pile pile stress test device, it is characterised in that agent structure includes miniature steel pipe pile, temperature certainly
Compensation mini optical fibre grating strain transducer string, sheathed wire, optical fiber grating sensing analyzer, data storage computer, sensing
Device mounting hole, hole excision plate and fairlead；It is pointed that the stake end of miniature steel pipe pile is welded into closing；Sensor mounting hole is with flame
For the mode of cutting in miniature steel pipe pile pore-forming, sensor mounting hole is 4cm × 7cm square-section, its long side and miniature steel pipe
The axis direction of stake is consistent, and the centre of form section of sensor mounting hole passes with each temperature self-compensation type mini optical fibre grating strain
The centre of form section of sensor overlaps；Temperature self-compensation type mini optical fibre grating strain transducer string is by temperature self-compensation type mini optical fibre
The quasi-distributed sensor string that grating strain transducer is connected into according to design requirement, temperature self-compensation type mini optical fibre grating should
Become the inner surface that sensor string is arranged in miniature steel pipe pile in a welding manner, temperature self-compensation type mini optical fibre grating strain passes
For the number of sensor according to determination is actually needed, there is clamping at each temperature self-compensation type mini optical fibre grating strain transducer both ends
Block, grip block are welded on miniature steel pipe pile, wherein the optical fiber between each temperature self-compensation type mini optical fibre grating strain sensing
And the optical fiber of extraction bottom surface is all protected with sheathed wire；Hole cuts off plate weld on miniature steel pipe pile surface and by sensor
Mounting hole is completely covered by, the end of a thread of temperature self-compensation type mini optical fibre grating strain transducer string by miniature steel pipe pile at the top of
Fairlead is drawn and is connected with optical fiber grating sensing analyzer, and optical fiber grating sensing analyzer is connected with data storage computer,
The bending angle of sheathed wire is not more than 90 degree during whole Installation And Test.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721305729.5U CN207215329U (en) | 2017-09-30 | 2017-09-30 | A kind of miniature steel pipe pile pile stress test device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721305729.5U CN207215329U (en) | 2017-09-30 | 2017-09-30 | A kind of miniature steel pipe pile pile stress test device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207215329U true CN207215329U (en) | 2018-04-10 |
Family
ID=61820862
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721305729.5U Active CN207215329U (en) | 2017-09-30 | 2017-09-30 | A kind of miniature steel pipe pile pile stress test device |
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| Country | Link |
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| CN (1) | CN207215329U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109682321A (en) * | 2019-01-02 | 2019-04-26 | 华中科技大学 | Distributed strain sensor-based system and its measurement method based on adaptive reference compensation |
| CN111560995A (en) * | 2020-05-28 | 2020-08-21 | 机械工业勘察设计研究院有限公司 | Device and method for testing internal force of cast-in-place pile by using optical fiber |
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2017
- 2017-09-30 CN CN201721305729.5U patent/CN207215329U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109682321A (en) * | 2019-01-02 | 2019-04-26 | 华中科技大学 | Distributed strain sensor-based system and its measurement method based on adaptive reference compensation |
| CN111560995A (en) * | 2020-05-28 | 2020-08-21 | 机械工业勘察设计研究院有限公司 | Device and method for testing internal force of cast-in-place pile by using optical fiber |
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