1、Designation: F3092 14Standard TerminologyRelating to Optical Fiber Sensing Systems1This standard is issued under the fixed designation F3092; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pa
2、rentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This terminology standard is a compilation of defini-tions of technical terms related to optical fiber sensing systems,used in the various sections
3、 of standards under the jurisdictionof ASTM Committee F36.1.2 Where possible definitions are stated as a singlesentence, with necessary supplementary information as aDiscussion. This approach is used to simplify explanations ofthe meanings of technical terms for the benefit of those notconversant wi
4、th them, to facilitate a precise understanding andinterpretation of F36 ASTM standards.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.2. Referenced Documents2.1 ASTM Standards:2F2233 Guide for Safety, Access Rights, Constru
5、ction,Liability, and Risk Management for Optical Fiber Net-works in Existing SewersF2303 Practice for Selection of Gravity Sewers Suitable forInstallation of Optical Fiber Cable and ConduitsF2304 Practice for Sealing of Sewers Using ChemicalGroutingF2349 Practice for Operation and Maintenance of Int
6、egratedNatural Gas Pipelines and Optical Fiber SystemsF2350 Practice for Selection of Natural Gas Pipelines Suit-able for Installation of Optical Fiber SystemsF2414 Practice for Sealing Sewer Manholes Using ChemicalGroutingF2454 Practice for Sealing Lateral Connections and linesfrom the mainline Sew
7、er Systems by the Lateral PackerMethod, Using Chemical GroutingF2462 Practice for Operation and Maintenance of Sewerswith Optical Fiber SystemsF2550 Practice for Locating Leaks in Sewer Pipes ByMeasuring the Variation of Electric Current Flow Throughthe Pipe WallF2551 Practice for Installing a Prote
8、ctive CementitiousLiner System in Sanitary Sewer Manholes3. Significance and Use3.1 Definitions in this standard are to be regarded as correctfor the terms found in other ASTM standards of CommitteeF36. Certain terms may be found in more than one standardissued under the jurisdiction of this committ
9、ee and many ofthese terms have been placed in this standard.4. Terminologyabsorption, nthe loss of some or all of the energy containedin an electromagnetic wave to the medium in which it ispropagating, usually converted to heat.acceptance angle, nthe maximum angle, measured from theoptical fiber cen
10、terline to an incident light ray, within whichthe incident ray will be accepted for transmission by totalinternal reflection along the fiber.DISCUSSIONIf the incident angle is greater than the acceptanceangle, total internal reflection will not occur and the incident ray will belost by leakage.acces
11、s rights, nagreements between various parties to obtaintemporary and permanent access to property for the purposeof constructing, maintaining, or changing optical fibernetworks. F2233accuracy, nthe closeness of the measured value to the true orthe ideal value of the parameter being measured and isaf
12、fected by both bias and precision.acoustic wave, nlongitudinal waves propagated by means ofadiabatic compression and decompression.acousto-optics, nthe science and technology of the interac-tions between sound waves and light waves passing throughmaterial media, especially as applied to the modulati
13、on anddeflection of laser beams by ultrasonic waves.acrylamide, norganic solid of white, odorless, acrylic resin-ous material available in flake-like crystals and in liquidform. The greatest use of acrylamide is as a coagulant aid in1This terminology is under the jurisdiction of ASTM Committee F36 o
14、nTechnology and Underground Utilities and is the direct responsibility of Subcom-mittee F36.10 on Optical Fiber Systems within Existing Infrastructure.Current edition approved July 1, 2014. Published August 2014. DOI: 10.1520/F309214.2For referenced ASTM standards, visit the ASTM website, www.astm.o
15、rg, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1drinking wate
16、r treatment. Other major uses of acrylamide arein soil stabilization, in grout for repairing sewers and inacrylamide gels used in biotechnology laboratories. F2414acrylate, na general term applied to various water-solubleacrylic resinous materials. F2414adit, nin tunneling, a tunnel driven from grou
17、nd surface toprovide access to or drainage from underground workings; alength of tunnel driven for an exploration-exploration adit.advance, nin tunneling, the forward progress in the construc-tion of a tunnel, usually measured by the length created, orthe rate of segment positioning in terms of a nu
18、mber perhour/day or some other timescale.ambient temperature, nthe temperature of the surroundingenvironment or air. F2304Angstrom, A, na unit of length equal to 10-1nanometer (10-1nm), 10-4micron (10-6mm), and 10-10meter (10-10m).annulus, nin tunneling, a ring-shaped opening, generallybounded by th
19、e outside diameter of excavated tunnel and theexterior of the final tunnel liner. F2304aperture, nin optics, a hole or an opening through whichlight travels.attenuation, nthe decrease in optical power of a signal, orlight wave, from interaction with the propagation medium,for example, absorption, re
20、flection, diffusion, scattering,deflection, dispersion or resistance.attenuation budget, nthe maximum cumulative one-way ortwo-way optical power loss between the interrogator and themeasurement point that allows a measurement with a speci-fied performance.attenuation range, ntotal cumulated optical
21、loss (one wayloss; expressed in decibels (dB) tolerated by the DRSsystem without affecting the specified measurement perfor-mance more than a given factor at a given location, spatialresolution, and measurement time.DISCUSSIONPart of the total cumulative loss can be the fiberattenuation, point defec
22、t losses introduced by components such asconnectors, splices, kink in the fiber, attenuators, etc.authorized inspector, nthe person(s) contracted or approvedby the owner or owners representative to do inspections.F2414backfill, nin tunneling, a material used to replace excavatedsoil.bandwidth, nthe
23、range of frequencies that a device iscapable of handling.beam splitter, nan optical device for dividing a light beaminto two separated beams.bench, nin tunneling, in situ ground at the lower face of atunnel undergoing staged excavation.bend loss, noptical power loss in an optical fiber becausesignal
24、 radiation escapes through its bends, with the magni-tude of optical power loss being proportional to the bendingradius.bending radius, nthe radius of a bend measured in a fiberoptic cable.bentonite, nclay composed mainly of clay mineralmontmorillonite, used for synthetic reasons, due to itsexpandin
25、g properties when in contact with water, forexample, drilling mud, binder, absorbent, groundwaterbarrier, etc.bias, nthe difference between the measured results afteraveraging, less the true value.birefringence, nthe separation of a light beam into twocomponents to form two rays propagating at diffe
26、rentvelocities in the medium.bolt pocket, nin tunneling, a pre-formed recess in tunnelsegment to accommodate bolts which hold segments to-gether.bore, nin tunneling, the internal diameter of a pipe or othercylinder, single tunnel, for example, twin bore.borehole, na hole driven into the ground to ge
27、t informationabout the strata, or to release water pressure by vertical sanddrains, or to obtain water, oil, gas, etc.boring/bored, nmaking a hole in the ground by means ofrotating auger.box jack/jacked box, nin tunneling, a fully constructedstructure that is thrust into final position from an adjac
28、entjacking point.Bragg cell, nan acousto-optic device that is capable ofmodulating light waves to produce an output light wave withan imposed frequency equal to the frequency of the inputsignal.Brillouin optical time domain analysis, BOTDA, ndoubleended access to the light source and detection syste
29、m forlong sensing lengths combined with high strain and tempera-ture resolution for up to 31 miles (50 km) without signalregeneration.Brillouin optical time domain reflectometer, BOTDR, nasingle ended access to the source and detection system,which provides a Brillouin gain-loss-based distribution s
30、en-sor much like the standard OTDR sensors which useRayleigh scattering to the same effect. See optical timedomain reflectometer.Brillouin scattering, nlight in a medium interacts withtime-dependent optical density variations and changes itsfrequency and path.DISCUSSIONThe density variations may be
31、due to acoustic modes,such as phonons, or magnetic modes, such as temperature gradients.Asdescribed in classical physics, when the medium is compressed itsindex of refraction changes, and a fraction of the traveling light wave,interacting with the periodic refraction index variations, is deflected a
32、sin a three-dimensional diffraction grating. Since the sound wave, too, istraveling, light is also subjected to a Doppler shift, so its frequencychanges.cable, na group of insulated light conductors that are boundtogether, usually with a durable cable jacket.F3092 142cable jacket, nthe outer protect
33、ive covering over insulatedconductors that are bound together.caisson, nin tunneling, a watertight retaining structure, thatcan be used as a support of excavation for a shaft structure.canopy tube, nin tunneling, a metal tube drilled into thetunnel face above the ground to be excavated, the tube isp
34、umped full of grout once in place; the canopy is createdusing multiple adjacent tubes to reduce the risk of crownfailure.catalyst, nsubstance which markedly speeds up the cure ofan adhesive when added in small quantities as compared tothe amounts of primary reactants. F2414caulking, none of several
35、different processes to seal joints orseams in various structures and piping. F2454character-separated value file format, CSV, nsynonymouswith “comma separated value file,” stores tabular data(numbers and text) in a sequence of characters, with no datathat has to be interpreted, separated by some cha
36、racter orstring, for example, comma or tab.characteristic frequency and/or wavelength at referencetemperature (Brillouin technologies), nthe frequencyand/or wavelength that characterizes the sensor response atreference temperature as monitored by the interrogator.DISCUSSIONAs Brillouin frequency var
37、ies with wavelength of thelight source, this also changes the temperature and strain coefficientsfor various sensing fibers. Therefore, characteristic frequency and thewavelength at a specified reference temperature and at zero strain areusually provided by the complete system producers.chemical gro
38、ut, ninjection repair media other than cemen-titious grout that may be multicomponent, with or withoutadditives, and based on either polyurethane resin or acrylicresin. F2414circumferential joint, nin tunneling, a joint (typically be-tween segments) which runs circumferentially relative to thetunnel
39、 bore.cladding, nin optics, optical transparent material over thecore of the optical fiber, with a refractive index lower thanthat of the core, to provide total internal reflectance.coherence length, nthe coherence time of a light beammultiplied by the velocity of the light.coherence time, nif t is
40、the time a light beam takes tobecome coherent, and t + t is the time at which the lightbeam loses its coherent properties, t is the coherence time.coherent light, nlight which has predictable parameters atany point in time or space, for example, laser bined sewers, nsewers that carry both wastewater
41、 andstorm or surface water. F2303compensation grouting, nin tunneling, a method of revers-ing ground settlements by injecting grout into the petent person, na person properly trained in the safetyaspects of an activity. F2233conductor, na transparent medium that is capable of trans-mitting or convey
42、ing light waves by total internal reflection.conduit, nplastic tubing used to house optical fiber cable thatis connected to, but not inside of, a pipeline. F2349, F2462confined space, nan enclosed area that is large enough andso configured that a person can bodily enter and has thefollowing characte
43、ristics: its primary function is somethingother than human occupancy; has restricted entry and exit.(Restricted entry and exit is a physical configuration whichrequires the use of hands or contortion of the body to enterinto or exit from the confined space.) F2233connector, ncoupling device attached
44、 to the end of a fiber sothat it can be mechanically connected to equipment or matedwith another connector to join two fibers together byaligning their cores to minimize signal loss.connector insertion loss, nthe power loss due to theinsertion of a connector between two elements.constructability, nt
45、he term used to denote the condition of acompleted set of plans and specifications for an optical fibernetwork and its impact to the host utility, which have beenprepared with an analysis of practical, feasible methods ofconstruction. F2233contractor, nusually, the entity in charge of construction o
46、fthe new tunnel or other infrastructure that may impact theutility. F2551control agent, nsubstance added which controls the viscos-ity or flow properties of the material it is added to. F2414convergence, nin tunneling, a measurement of the inwardmovements of tunnel walls, often monitored to providei
47、nformation on the performance of the lining during con-struction.conveyor, nin tunneling, used to remove excavated materialfrom a tunnel face or shaft.core, nthe primary light-conducting region of an opticalfiber. The refractive index of the core is higher than itscladding, the condition necessary f
48、or total internal reflection.coupler, na mechanical connector that is used to interconnecttwo or more optical fibers.coupler 3-dB, na coupler that splits the optical energy in anoptical waveguide into two equal parts and couples each partinto a separate waveguide; ideally distributes 50 % of theinpu
49、t optical power to each of the output channels.coupling, nthe connection between elements, whether physi-cal or across a gap, where energy from one element istransferred to one or more other elements.coupling loss, nthe power loss caused by the coupling.coupling ratio, nthe ratio of the output power to the inputpower.covered tasks, nan activity, identified by the operator, that isperformed on a pipeline; is an operations and maintenanceF3092 143task; is performed as a requirement of t
