CN110332902B - Distributed optical fiber fixing device and method for monitoring deformation of slide-resistant pile - Google Patents
Distributed optical fiber fixing device and method for monitoring deformation of slide-resistant pile Download PDFInfo
- Publication number
- CN110332902B CN110332902B CN201910637701.9A CN201910637701A CN110332902B CN 110332902 B CN110332902 B CN 110332902B CN 201910637701 A CN201910637701 A CN 201910637701A CN 110332902 B CN110332902 B CN 110332902B
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- clamp
- slide
- fixing
- fiber fixing
- 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.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/16—Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
Abstract
The invention provides a distributed optical fiber fixing device for monitoring the deformation of an anti-slide pile, which comprises an optical fiber, an optical fiber traction tool and a plurality of optical fiber fixing clamps, wherein the optical fiber traction tool comprises a sliding table, and an active sliding block, an optical fiber traction clamp and a driving assembly which are arranged on the sliding table, the driving assembly is connected with the active sliding block and drives the active sliding block to slide on the sliding table, the active sliding block is connected with the optical fiber traction clamp, the sliding table is used for fixing the optical fiber traction tool on the anti-slide pile, the optical fiber traction clamp is used for clamping the optical fiber, the driving assembly is used for drawing the optical fiber to tension the optical fiber, and all the optical fiber fixing clamps are fixed on the. The invention has the beneficial effects that: the optical fiber is fixed by the optical fiber fixing clamp in a segmented mode, the problem that the optical fiber sensor is easy to be extruded, dislocated and bent to generate uneven initial strain in the traditional laying method is solved, and the problem that the optical fiber sensor is insensitive to compressive strain in a natural stretching state is effectively solved.
Description
Technical Field
The invention relates to the technical field of distributed optical fiber sensing, in particular to a distributed optical fiber fixing device and method for monitoring the deformation of an anti-slide pile.
Background
The basic principle of the distributed optical fiber sensing technology is that when an optical fiber sensor is subjected to axial stress or temperature change, optical wave characteristic parameters such as phase, frequency, polarization state and the like transmitted in an optical fiber can be changed correspondingly, and information of external measured parameters can be obtained by detecting the change of the parameters. The distributed optical fiber sensing technology based on Brillouin scattering is widely applied to the fields of geotechnical engineering and structural object health monitoring, and the frequency shift change of Brillouin scattering light has a linear relation with the axial strain/temperature of the optical fiber.
The essence of landslide control is to change the landslide evolution process, and the anti-slide pile is one of the most widely applied prevention and control measures in the landslide control project. The research on the interaction between the landslide and the anti-skid structure is mainly carried out on the basis of the research on the bearing characteristics of the anti-skid structure, so that the accurate and effective acquisition of the bearing characteristics of the anti-skid structure is very important. With the maturity of distributed optical fiber sensing technology and the commercial operation of related equipment, there are many students trying to monitor the deformation stress state of the anti-slide pile by using distributed optical fiber. The essence of monitoring the deformation stress state of the slide-resistant pile by using the distributed optical fiber sensing technology is that the optical fiber sensor is implanted into the slide-resistant pile to enable the optical fiber sensor and the slide-resistant pile to cooperatively deform, and then the axial strain value of each point of the slide-resistant pile where the optical fiber sensor is located is obtained. At present, the minimum monitoring sampling interval based on the Brillouin Optical Time Domain Analysis (BOTDA) technology can reach 1cm, and the engineering requirements can be completely met.
Regarding the arrangement mode of the optical fiber sensors in the slide-resistant piles, the optical fiber sensors are generally bound on vertical stressed steel bars in the slide-resistant piles by the predecessors by adopting iron wires or rubber belts and are formed by pouring along with concrete. Although the method is simple to operate, the method has several defects, and the monitoring result is greatly influenced. 1. From the test results of a plurality of publicly published papers and subject groups, the method can cause the initial strain value of the optical fiber sensor in the same axial direction to have larger fluctuation, and has larger difference with the theoretically due strain uniform state, because the optical fiber sensor is in a loose state when being installed, the optical fiber sensor is easy to be pushed by granular substances to generate transverse deformation in the concrete pouring process, and the method for monitoring the deformation of the slide-resistant pile by adopting the optical fiber sensor is based on the integral operation of the strain value of each point on the optical fiber sensor, so that the initial state of the optical fiber sensor is influenced, and meanwhile, certain influence is generated on the subsequent deformation monitoring calculation; 2. an armored optical fiber sensor is generally adopted in concrete structure monitoring, which can affect the strain transmission efficiency to a certain extent, and especially can generate larger error when small strain occurs on the optical fiber sensor in a relaxed state; 3. the optical fiber sensor has insensitivity to compressive strain, and is shown in the deformation of the slide-resistant pile that one side of the slide-resistant pile is pressed and the other side of the slide-resistant pile is pulled, and the change of the compressive strain on the pressed side is difficult to monitor by adopting a simple binding mode.
Disclosure of Invention
In view of this, embodiments of the present invention provide a distributed optical fiber fixing device and method for monitoring slide pile deformation.
The embodiment of the invention provides a distributed optical fiber fixing device for monitoring the deformation of an anti-slide pile, which comprises an optical fiber, an optical fiber traction tool and a plurality of optical fiber fixing clamps, wherein the optical fiber traction tool comprises a sliding table, and an active sliding block, an optical fiber traction clamp and a driving assembly which are arranged on the sliding table, the driving assembly is connected with the active sliding block and drives the active sliding block to slide on the sliding table, the active sliding block is connected with the optical fiber traction clamp, the sliding table is used for detachably fixing the optical fiber traction tool on longitudinal steel bars of the anti-slide pile, the optical fiber traction clamp is used for clamping the optical fiber, the driving assembly is used for drawing the optical fiber to tension the optical fiber, and all the optical fiber fixing clamps are fixed on the longitudinal steel bars of the anti-slide pile at intervals along the extension direction of the optical fiber and are.
Further, drive assembly is screw assembly, including parallel arrangement's lead screw and optical axis, the lead screw with the both ends of optical axis are all fixed in on the slip table, lead screw threaded connection the initiative slider, the optical axis runs through the initiative slider.
Further, the optical fiber fixing clamp comprises an upper nut, a lower nut and a three-piece clamping jaw, the two ends of the three-piece clamping jaw are thin, the middle of the three-piece clamping jaw is thick, external threads are arranged on the surface of the three-piece clamping jaw, and the two ends of the three-piece clamping jaw are sleeved with the upper nut and the lower nut respectively and are in threaded connection.
Further, the upper nut is provided with a notch for the side wall, and the notch vertically penetrates through the upper nut and is communicated with the inner hole of the upper nut.
Further, optic fibre mounting fixture still includes first clamp, first clamp fixed connection three lamella jack catchs middle part just can be fixed in on the longitudinal reinforcement of friction pile.
Further, the optical fiber drawing tool further comprises a pressure sensor and a passive sliding block, the lower end of the drawing pressure sensor is connected with the active sliding block, the upper end of the drawing pressure sensor is connected with the passive sliding block, and the drawing pressure sensor is used for monitoring the tension of the optical fiber.
Further, optic fibre tractive instrument still includes connecting wire and reading appearance, the reading appearance is fixed in on the slip table, the connecting wire is connected draw pressure sensor with the reading appearance.
Further, the slip table is equipped with detachable second clamp, the second clamp is used for dismantling fixed connection the longitudinal reinforcement of friction pile.
The embodiment of the invention also provides a distributed optical fiber fixing method for monitoring the deformation of the slide-resistant pile, which uses the distributed optical fiber fixing device for monitoring the deformation of the slide-resistant pile and comprises the following steps,
s1, fixing all the optical fiber fixing clamps on the longitudinal steel bars of the slide-resistant pile before pouring at intervals;
s2, the optical fiber passes through all the optical fiber fixing clamps in sequence;
s3, adjusting the optical fiber fixing clamp at the top or the bottom to clamp the optical fiber;
s4 fixing the optical fiber drawing tool on the longitudinal steel bar above the optical fiber fixing clamp adjacent to the last clamping optical fiber fixing clamp, controlling the optical fiber drawing tool to tension the optical fiber, then adjusting the optical fiber fixing clamp to clamp the optical fiber, and detaching the optical fiber drawing tool from the longitudinal steel bar;
s5 repeating step S4 a plurality of times until the fiber securing clamps each clamp the fiber.
Further, the fiber drawing tool is controlled to tension the optical fiber in step S4, so that the strain generated by the optical fiber is about 3000 μ.
The technical scheme provided by the embodiment of the invention has the following beneficial effects: according to the distributed optical fiber fixing device and method for monitoring the deformation of the slide-resistant pile, the optical fiber is fixed in a segmented mode through the optical fiber fixing clamp, so that the position of the optical fiber sensor in the slide-resistant pile is restrained, and the problem that the optical fiber sensor is prone to being extruded, dislocated and bent to generate uneven initial strain in the traditional laying method is solved. In addition, the optical fiber has certain initial tensile strain, the compression state of the optical fiber sensor is converted into resilience of the tension state, and the problem that the compression strain of the optical fiber sensor is insensitive in a natural extension state is effectively solved.
Drawings
FIG. 1 is a schematic view of a distributed optical fiber fixing device for monitoring the deformation of a slide-resistant pile according to the present invention;
FIG. 2 is a cross-sectional view of the fiber pulling tool 1 of FIG. 1;
fig. 3 is a cross-sectional view of the optical fiber fixing jig 2 in fig. 1.
In the figure: 1-optical fiber fixing clamp, 101-first clamp, 102-three-jaw, 103-nut, 104-notch, 2-optical fiber drawing tool, 201-sliding table, 202-hand wheel, 203-screw rod, 204-active sliding block, 205-passive sliding block, 206-optical fiber drawing clamp, 207-optical axis, 208-drawing pressure sensor, 209-connecting wire, 210-reading instrument, 211-second clamp, 212-baffle, 3-optical fiber and 4-reinforcing steel bar.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be further described with reference to the accompanying drawings.
Referring to fig. 1, an embodiment of the present invention provides a distributed optical fiber fixing device for monitoring slide pile deformation, including an optical fiber 3, an optical fiber pulling tool 2, and a plurality of optical fiber fixing clamps 1.
Referring to fig. 2, the optical fiber drawing tool 2 includes a sliding table 201, and an active slider 204, a passive slider 205, an optical fiber drawing jig 206, a drawing pressure sensor 208 and a driving assembly which are disposed on the sliding table 201, where the sliding table 201 is a rectangular sliding table, and both upper and lower ends of the sliding table are provided with a baffle 212. The back of slip table 201 is equipped with a plurality of second clamps 211 of detachable, second clamp 211 is used for dismantling fixed connection the longitudinal reinforcement 4 of friction pile. In this embodiment, the number of the second clips 211 is two.
The active slider 204, draw pressure sensor 208 with passive slider 205 all set up in on the slip table 201 and be located two between the baffle 212, passive slider 205 set up in the top of active slider 204, draw pressure sensor 208 upper end to connect passive slider 205, lower extreme fixed connection active slider 204, optic fibre tractive anchor clamps 206 are fixed in on the passive slider 205. In this embodiment, the optical fiber drawing clamp 206 is two clamping blocks connected by a bolt, and the two clamping blocks are used for clamping the optical fiber 3.
The tension pressure sensor 208 is used for measuring the tension of the optical fiber 3, in order to observe the tension of the optical fiber 3 conveniently, a reading instrument 210 is arranged on the sliding table 201, the reading instrument 210 is connected with the tension pressure sensor 208 through a connecting wire 209, and the reading instrument 210 is fixed on one side of the sliding table 201 in the embodiment.
Drive assembly is screw assembly, including parallel arrangement's lead screw 203 and two optical axis 207, two the upper and lower both ends of optical axis 207 are fixed in two respectively on the baffle 212, lead screw 203 sets up in two between the optical axis 207, lead screw 203 upper end runs through one baffle 212 and a hand wheel 202 is connected, lead screw 203 middle part is run through initiative slider 204 and with initiative slider 204 threaded connection, the lead screw 203 other end runs through another baffle 212, and two the optical axis still runs through simultaneously passive slider 205, it is right passive slider plays the effect of spacing direction when sliding, hand wheel 202 rotates and drives lead screw 203 rotates, makes initiative slider 204 along optical axis 207 elevating movement.
Referring to fig. 3, the optical fiber fixing clamp 1 includes two nuts 103 and a three-piece jaw 102, the three-piece jaw 102 has two thin ends and a thick middle part, the surface of the three-piece jaw 102 is provided with external threads, and the two nuts 103 are an upper nut, a lower nut, and the upper nut and the lower nut respectively sleeve the two ends of the three-piece jaw 102 and are in threaded connection. The three-piece claw 102 is in an unfolded state in a natural state, and the upper nut and the lower nut are tightened to close the three-piece claw 102 so as to clamp the optical fiber 3. The upper nut side wall is provided with a notch 104, the notch 104 vertically penetrates through the upper nut and is communicated with the inner hole of the upper nut, the notch 104 is convenient for the optical fiber 3 to penetrate into the three-piece clamping jaw 102, and the lower nut is identical to the upper nut in structure. The notch 104 in this embodiment is a rectangular notch extending radially along the inner bore of the upper nut. In order to facilitate the optical fiber fixing clamp 1 to be fixed on the longitudinal steel bar 4 of the slide-resistant pile, a first clamp 101 is arranged on the outer wall of the three-piece clamping jaw 102, the first clamp 101 comprises two clamping rings which are connected into a whole, one clamping ring is sleeved on and fixedly connected with the three-piece clamping jaw 102, and the other clamping ring can be detachably connected with the longitudinal steel bar 4 of the slide-resistant pile. The number of the optical fiber fixing clamps 1 is determined according to the length of the slide-resistant piles.
The embodiment of the invention also provides a distributed optical fiber fixing method for monitoring the deformation of the slide-resistant pile, which uses the distributed optical fiber fixing device for monitoring the deformation of the slide-resistant pile and comprises the following steps,
s1, fixing all the optical fiber fixing clamps 1 on the longitudinal steel bar 4 of the slide-resistant pile before casting at intervals, wherein firstly, according to the length of the slide-resistant pile, a proper number of optical fiber fixing clamps 1 are selected, and each optical fiber fixing clamp 1 is fixed on the longitudinal steel bar 4 through the first clamp 101, and a proper distance is kept between two adjacent optical fiber fixing clamps 1;
s2 passing the optical fiber 3 through all the optical fiber fixing clamps 1 in sequence, wherein the three-jaw 102 of each optical fiber fixing clamp 1 is in an unfolded state, so that the optical fiber 3 is constrained in the optical fiber fixing clamp 1 and is not clamped;
s3 adjusting the optical fiber fixing clamp 1 at the top or the bottom to clamp the optical fiber 3, in this embodiment, the optical fiber fixing clamp 1 at the bottom is adjusted to clamp the optical fiber 3 by tightening the upper nut and the lower nut;
s4 fixing the optical fiber drawing tool 2 on the longitudinal steel bar 4 above the optical fiber fixing clamp 1 adjacent to the last clamped optical fiber fixing clamp 1, controlling the optical fiber drawing tool 2 to tension the optical fiber 3 to generate a strain of about 3000 μ on the optical fiber 3, adjusting the optical fiber fixing clamp 1 to clamp the optical fiber, and detaching the optical fiber drawing tool 2 from the longitudinal steel bar;
s5 repeats step S4 a plurality of times until the optical fibers 3 are clamped by the optical fiber fixing clamps 1.
The magnitude of the optical fiber pulling force should be tested according to the elastic modulus of different optical fiber types to determine the appropriate pulling force value.
In this document, the terms front, back, upper and lower are used to define the components in the drawings and the positions of the components relative to each other, and are used for clarity and convenience of the technical solution. It is to be understood that the use of the directional terms should not be taken to limit the scope of the claims.
The features of the embodiments and embodiments described herein above may be combined with each other without conflict.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (2)
1. A distributed optical fiber fixing method for monitoring the deformation of an anti-slide pile is characterized by comprising the following steps: the distributed optical fiber fixing device for monitoring the deformation of the slide-resistant pile comprises an optical fiber, an optical fiber traction tool and a plurality of optical fiber fixing clamps, the optical fiber traction tool comprises a sliding table, and an active sliding block, an optical fiber traction clamp and a driving assembly which are arranged on the sliding table, the driving component is connected with the driving sliding block and drives the driving sliding block to slide on the sliding table, the active sliding block is connected with the optical fiber traction clamp, the sliding table is used for detachably fixing an optical fiber traction tool on the longitudinal steel bar of the slide-resistant pile, the optical fiber drawing clamp is used for clamping the optical fiber, the driving assembly is used for drawing the optical fiber to tension the optical fiber, and all optical fiber fixing clamps are fixed on the longitudinal steel bars of the slide-resistant pile at intervals along the extending direction of the optical fiber and used for clamping the optical fiber in a segmented mode;
and comprises the following steps of,
s1, fixing all the optical fiber fixing clamps on the longitudinal steel bars of the slide-resistant pile before pouring at intervals;
s2, the optical fiber passes through all the optical fiber fixing clamps in sequence;
s3, adjusting the optical fiber fixing clamp at the top or the bottom to clamp the optical fiber;
s4 fixing the optical fiber drawing tool on the longitudinal steel bar above the optical fiber fixing clamp adjacent to the last clamped optical fiber fixing clamp, controlling the optical fiber drawing tool to tension the optical fiber, adjusting the optical fiber fixing clamp adjacent to the clamped optical fiber fixing clamp to clamp the optical fiber, and detaching the optical fiber drawing tool from the longitudinal steel bar;
s5 repeating step S4 a plurality of times until the fiber securing clamps each clamp the fiber.
2. The distributed optical fiber fixing method for monitoring the deformation of the slide-resistant pile, according to claim 1, wherein: in step S4, the optical fiber drawing tool is controlled to tension the optical fiber, so that the strain generated by the optical fiber is 3000 μ.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910637701.9A CN110332902B (en) | 2019-07-15 | 2019-07-15 | Distributed optical fiber fixing device and method for monitoring deformation of slide-resistant pile |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910637701.9A CN110332902B (en) | 2019-07-15 | 2019-07-15 | Distributed optical fiber fixing device and method for monitoring deformation of slide-resistant pile |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110332902A CN110332902A (en) | 2019-10-15 |
| CN110332902B true CN110332902B (en) | 2020-12-15 |
Family
ID=68145205
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910637701.9A Active CN110332902B (en) | 2019-07-15 | 2019-07-15 | Distributed optical fiber fixing device and method for monitoring deformation of slide-resistant pile |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110332902B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113137951B (en) * | 2021-05-19 | 2022-01-11 | 中国地质大学（武汉） | Ground settlement monitoring device and implementation method thereof |
| CN113418460A (en) * | 2021-06-10 | 2021-09-21 | 中国地质大学（武汉） | Pipeline deformation monitoring device and method based on optical fiber sensor |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0921661A (en) * | 1995-07-06 | 1997-01-21 | Sumitomo Electric Ind Ltd | Apparatus for monitoring underground state of anchor construction part |
| CN101694372A (en) * | 2009-09-30 | 2010-04-14 | 武汉理工大学 | Intelligent cable fiber grating strain sensor |
| CN201614548U (en) * | 2010-02-08 | 2010-10-27 | 法尔胜集团有限公司 | Mounting structure of built-in fiber grating strain transducer of cable |
| BR112013020328A2 (en) * | 2011-04-07 | 2017-11-14 | Omnisens Sa | method and assembly to detect permanent deformation of a structure |
| CN103105138A (en) * | 2013-01-08 | 2013-05-15 | 中国航空工业集团公司北京长城计量测试技术研究所 | Fiber bragg grating strain sensitivity calibration device and method |
| CN104132622B (en) * | 2014-07-10 | 2015-03-25 | 河海大学 | Distributed optical fiber deformation tensile instrument and test method |
| CN105696633B (en) * | 2016-03-31 | 2018-08-07 | 中国电建集团华东勘测设计研究院有限公司 | A kind of friction pile supporting effect monitoring system and monitoring method |
| CN107941163B (en) * | 2017-12-22 | 2019-07-23 | 中国地质大学（武汉） | A kind of fully distributed fiber coefficient of strain caliberating device and method |
| CN208075789U (en) * | 2018-04-25 | 2018-11-09 | 中国计量大学 | A kind of Brillouin light fiber sensor system strain calibrating installation |
| CN108692771A (en) * | 2018-07-13 | 2018-10-23 | 中铁二院工程集团有限责任公司 | A kind of twisted steel anchor rod resultant stress optical fiber monitoring device |
-
2019
- 2019-07-15 CN CN201910637701.9A patent/CN110332902B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110332902A (en) | 2019-10-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110332902B (en) | Distributed optical fiber fixing device and method for monitoring deformation of slide-resistant pile | |
| RU2611092C2 (en) | Device and method of determining tension on guide cable of hanging scaffolds during well construction | |
| CN101387571A (en) | Dynamic mechanical test method and device for submarine optical fiber cable | |
| CN207050903U (en) | Force measuring device in a kind of drag-line based on cable body strain | |
| Askins et al. | Bend and twist sensing in a multiple-core optical fiber | |
| CN107941163B (en) | A kind of fully distributed fiber coefficient of strain caliberating device and method | |
| CN106124168B (en) | A kind of fiber stress strain testing method | |
| CN105043613A (en) | Cable stress measuring device based on fiber grating sensing technology | |
| US11733135B2 (en) | Integral tension test system for large-tonnage basalt fiber anchor cable and test method | |
| CN210243350U (en) | Experimental device for be used for detecting slice material performance | |
| CN114062248B (en) | System and method for testing friction resistance value of free section of rock-soil anchor cable pipeline | |
| CN105865655A (en) | Simultaneous temperature and strain measuring method based on interaction between acoustic and optical modes in optical fibers | |
| CN107152979A (en) | Clipping cable cable power monitoring device | |
| KR20140052170A (en) | Device for sensing the strain of structure steel strand and sensing system with the same | |
| CN101614634B (en) | Method for detecting opposite angle strength of fishing gear cod-end meshes of netting or trawl net of aquaculture net cage | |
| EP0452421A1 (en) | Fiber testing apparatus and method. | |
| CN104913988A (en) | Hopkinson principle-based concrete axial tensile strength measuring method | |
| CN105403339A (en) | Anchor pole force measuring apparatus, anchor pole and anchor pole tension measuring method | |
| RU133301U1 (en) | STAND FOR TESTING AND DETERMINING THE PHYSICAL PARAMETERS OF AN OPTICAL CABLE | |
| NL2030040A (en) | Device and method for testing overall anchorage performance of basalt fiber reinforced plastic (bfrp) anchor cable | |
| CN209783627U (en) | tensile, compression, vibration and alternating damp-heat fatigue testing device for optical fiber sensor | |
| CN110186386B (en) | Large deformation test device and method based on distributed optical fiber small strain | |
| CN110686818A (en) | Method for rapidly measuring cable force of steel strand stay cable | |
| CN202547682U (en) | Spatial resolution calibration device of Brillouin optical time domain demodulator | |
| CN109060518A (en) | A kind of tensile test fixture of long test specimen |
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 |