• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Brillouin optical time-domain analysis for geotechnical monitoring

    2015-02-09 01:29:00ZeniPirelliAvolioCosettPpZeniDiMioVsslloMinro

    L.Zeni,L.Pirelli,B.Avolio,A.Cosett,R.Pp,G.Zeni,C.Di Mio, R.Vssllo,A.Minro

    aDIII,Second University of Naples,Aversa,Italy

    bInstitute for Electromagnetic Sensing of the Environment(IREA),National Research Council,Napoli,Italy

    cDICDEA,Second University of Naples,Aversa,Italy

    dSchool of Engineering,University of Basilicata,Potenza,Italy

    Brillouin optical time-domain analysis for geotechnical monitoring

    L.Zenia,b,*,L.Picarellic,B.Avolioc,A.Coscettaa,R.Papac,G.Zenib,C.Di Maiod, R.Vassallod,A.Minardoa

    aDIII,Second University of Naples,Aversa,Italy

    bInstitute for Electromagnetic Sensing of the Environment(IREA),National Research Council,Napoli,Italy

    cDICDEA,Second University of Naples,Aversa,Italy

    dSchool of Engineering,University of Basilicata,Potenza,Italy

    A R T I C L EI N F O

    Article history:

    Received 30 November 2014

    Received in revised form

    8 January 2015

    Accepted 26 January 2015

    Available online 9 May 2015

    Brillouin optical time-domain analysis

    (BOTDA)

    Tunnel engineering

    Deformation

    Distributed monitoring

    Health diagnosis

    In this paper,we show some recent experimental applications of Brillouin optical time-domain analysis (BOTDA)based sensors for geotechnical monitoring.In particular,how these sensors can be applied to detecting early movements of soil slopes by the direct embedding of suitable fber cables in the ground is presented.Furthermore,the same technology can be used to realize innovative inclinometers,as well as smart foundation anchors.

    ?2015 Institute of Rock and Soil Mechanics,Chinese Academy of Sciences.Production and hosting by Elsevier B.V.All rights reserved.

    1.Introduction

    Distributed fber-optic strain sensors have great potentialities in the feld of geotechnical monitoring(Dewynter et al.,2009; Olivares et al.,2009;Iten,2011;Minardo et al.,2014).By integrating a single fber-optic cable into soil or a geotechnical work,a large number of accurate,spatially resolved data can be obtained. The Brillouin optical time-domain analysis(BOTDA)method allows for strain measurements in the microstrain range,with a typical spatial resolution of 1 m and a maximum sensing range of 50 km. This means that thousands of“strain gauges”along a single cable connected to structures,embedded in soil or grouted into boreholes,for example,can provide information about the current state of the object under supervision.The objects can include geological and civil structures,such as a construction site,a tunnel,a landslide prone area,or a pipeline.It is evident that such a technology implies a beneft for placing fber-optic cables anywhere possible on construction sites and in the green feld(Minardo et al.,2012).

    This paper summarizes some results of experiments carried out byresearch staff at Second University of Naples.Inparticular,aftera brief description of the sensor technology,three applications of the BOTDA technology in the geotechnical feld will be described:(a) slope monitoring by optical fbers embedded into the soil;(b) detection of soil movement by use of an optical fber based inclinometer;(c)monitoring of a ground anchor by use of an embedded optical fber.

    2.Principle of operation of BOTDA

    The experimental results reported in this paper have been conducted exploiting stimulated Brillouin scattering(Boyd,2008)in single-mode optical fbers.In brief,two counter-propagating lightwaves exchange energy along the fber,in a measure depending on their frequency offset.If the offset falls within a specifc range,the radiation at higher frequency(pump wave)transfers energy to that at lower frequency(Stokes wave).The sensing principle is based on the fact that the frequency difference at which the maximum amplifcation of the Stokes wave occurs,known as Brillouin frequencyshift(BFS),variesdependingonthemechanicalandthermal states of the fber.In particular,the BFS increases with both temperature and strain.Spatial resolution,i.e.the ability to measure deformation and temperature changes in a distributed way,can be achieved through the use of a pulsed pump beam:in this way,the interaction takes place along successive sections of the fber as the pump pulse propagates down the sensing cable.By recording the intensity of the Stokes radiation as a function of time,the Brillouin gaincanbetracedineachsection.Themeasurementof theBrillouin gain as a function of time and frequency allows the entire profle ofBrillouin shift along the fber to be obtained,which in turn can be translated in terms of deformation or temperature through the use of appropriate calibration coeffcients.

    Fig.1 shows the basic confguration employed for BOTDA.The pulsed and continuous wave(CW)beams are generated by two separated sources having lasing frequenciesν0andν0±νB,shifted by a defnite quantity in the range of the Brillouin frequency shift of the sensing fber.Fig.1 shows that the amplifcation of the Stokes beam occurs at those locations where the frequency offset with the crossing pulse matches the local Brillouin frequency shift,which in turn is related to the temperature(or strain)of the analyzed fber coil.More in general,Brillouin time-domain signals are acquired in BOTDA systems for a range of frequency offsets,so as to get a full picture of the Brillouin frequency shift at each location.

    Fig.1.Basic confguration for BOTDA:(a),(b)and(c)show the waveform of optical power at detector(Pd),acquired when the frequency offset between the two lasers is tuned to the Brillouin frequency shiftνBof fber coils 1,2 and 3,placed at temperaturesT1,T2andT3,respectively.

    3.Experiments on small-scale model slopes

    The main requirements of monitoring systems in areas susceptible to sudden and rapid landslides should be the following:(a) a cheap and reliable instrumentation;(b)continuous monitoring in time and space;(c)low probability of error to avoid false or missed alarms.

    For their ability to measure strainwith spatial continuity,optical fbers are particularly attractive.For this reason,we decided to check their performance in the monitoring of slopes in loose unsaturated granular soils susceptible to catastrophic rainfall-induced fowslides.The basic idea is that a sensing fber buried in the soil can detect the deformation due to ongoing volumetric and/or shear strains induced by the decrease in suction,which can be interpreted as a warning of incoming failure.The capability of the fber to provide distributed strain readings should allow to detect ongoing deformation at any point of even very long slope sections. This is a fundamental advantage with respect to conventional monitoring devices(topographic readings,inclinometers,etc.) which can provide information only at specifc points.The low cost of fbers is another relevant advantage.

    This simple idea suggested an experimental program to test this new kind of sensors in small-scale model slopes subjected to artifcial rainfall.The slopes are made of volcanic ash laid down into a fume imposing the same porosity as in the feld.The water infltration induced by artifcial rain causes an increase in the water content and a decrease in suction and,consequently,volumetric and shear strains;this mechanical process can lead to slope failure. The basic equipment for monitoring includes tensiometers,pore pressure transducers,laser displacement transducers,electrical moisture probes(TDRs)and video-cameras(see Fig.2).For the present application the fume was tilted with an inclination of 40°, and equipped with tensiometers,displacement sensors and optical fbers.The latter was a tight-buffer standard single-mode fber for telecommunications having an overall diameter of 900μm.The optical fber sensor was buried into the ground along two alignments parallel to each other(Fig.2).The model slopes,as a proof of principle,have been made up with volcanic ashes taken from the site of Cervinara,Italy,where feld monitoring is being carried out (Pirone et al.,2012).The slope has a length of 1.35 m,thickness of 10 cm,initial water content ranging between 43%and 50%,and porosity close to the feld value(70%-76%).

    In the experiment,a system of anchoring constituted by small plastic grids glued every 20 cm at the fber was adopted,as shownin Fig.3a.Fig.3b shows the position of the tensiometers and of the laser displacement sensors.

    Fig.2.The instrumented fume.

    The readings of the optical fber sensorare reported in Fig.4.The increase in Brillouin frequency shift from the initial profle(t=0), which reveals a state of stress due to accumulated strains during a frst test stage not reported here,to the latest one(t=47 min),is about 200 MHz.This corresponds to a deformation of about 0.4%. The collapse of the slope occurs after 50 min.Readings recorded after failure(t>tf)show that the Brillouin frequency shift returns to its initial value.

    For the sake of comparison,the readings of the tensiometers and displacement sensors are reported in Figs.5a and b,respectively.As it can be seen from Fig.5,the soil is completely saturated at surface before any settlement begins,while the saturation of the deep layer is complete only when a vertical displacement of the soil of a few millimeters is recorded.On the other hand,the optical fber sensors,being deployed in order to detect the soil sliding,start measuring a signifcant tensile strain when the early signs of the slope sliding occur.

    Fig.3.(a)Sensing fber anchored to the soil deposit.(b)Position of the tensiometers (T)and displacement sensors(L).

    4.Optical fber inclinometer

    An inclinometer based on BOTDA has been devised and realized. Its main characteristics can be summarized as follows:(a)measurement of three-dimensional(3D)deformation of soil;(b) continuous monitoring from a remote site and multiplexing capability;(c)self-compensation against temperature variations;(d) displacement sensitivity as high as 1 mm over 1 m;(e)safe operation up to overall displacements as large as 15 cm over 1 m,the limit being posed just by the breaking of the sensing optical fber.

    It should be emphasized that the above characteristics are not fulflled by traditional inclinometers which usually require periodic inspections for interrogation,and become useless if the displacement reaches values as large as to prevent the sliding of the measuring head along the inclinometer tube itself(a few centimeters of movement across a narrow slip plane).

    The optical fber inclinometer is realized by epoxy-gluing four equally spaced fbers along the surface of a PVC pipe for its entire length,as shown in Fig.6.

    The pipe is 50 mm in diameter,and 3.2 mm in thickness,while its overall length is 750 cm,achieved by connecting three pipe sections of 250 cm.The measurement of the strain profles along the fbers allows the reconstruction of the 3D deformation of the pipe and,consequently,the movements of the soil wherethe pipe is embedded(Lenke et al.,2011).

    In order to assess the validity of the proposed approach,several laboratory tests were performed on the inclinometer tube before on-site installation.Fig.7a shows the selection of the results achieved during the laboratory tests.In detail,we show the vertical displacement along a 180 cm-long pipe,with identical crosssection of the pipe used on-site,subjected to prescribed displacement at one end and fxed on the other end.The displacements retrieved by the optical fber sensor using a Brillouin shift sensitivity to strain of 417 MHz/%and a spatial resolution of 20 cm,are compared to the ones provided by eight dial gauges distributed along the pipe.It is seen that the agreement is remarkably good.In particular,the maximum deviation between the dial gauge and optical fber displacement was about 4 mm,while the standard deviation of the measurement error was about 1 mm.Note that the observed discrepancy is coherent with an error analysis of the displacement.In fact,assuming a strain uncertaintyσε=100με,we can calculate the standard deviation of the displacement simply bywhereLandDrepresentthe pipe length and diameter,respectively; Δzis the spatial resolution.This equation shows that the variance of displacement grows with the pipe length,thus the proposed method may suffer from inaccuracies for relatively long pipes.

    Fig.4.Temporal sequences of the Brillouin shift along the fber.

    Fig.5.(a)Suctionua-uw,whereuaanduware the air pressure and the pore water pressure,respectively.(b)Vertical displacementuz.

    In regard to on-site measurement results,the selected test site was an area,located in Basilicata Region,Italy,subjected to slowsoil movements and already instrumented with traditional inclinometer tubes.The test site is depicted in Fig.8,where the positions of the traditional inclinometers and the fber optic one are shown,as well.

    The optical fber inclinometer was installed in a 750 cm deep borehole which was then flled with grout.After allowing the grout cure for one month,a frst measurement was performed as a reference in order to eliminate all the strain induced by the installation procedure.

    The subsequent measurements allow the detection of any soil movements.Fig.9 shows the obtained results.Despite its limited length,the fber optical inclinometer exhibits a suffcient accuracy in detecting the maximum pipe displacement at the ground surface.

    Fig.6.The optical fber inclinometer tube.

    5.A“smart”foundation anchor

    For this experiment,a smart foundation anchor was devised and realized.The main objective of this activity was to improve the understanding of the anchor’s load bearing behavior,as the performance of the anchor is limited by the effciency of load transfer from the anchor tendon to the soil via the grout(Iten, 2011).

    In brief,the anchor was equipped with an optical fber epoxyglued inside the steel tendon.The optical fber was disposed in a loop confguration so as to have both ends available for BOTDA distributed strain measurements.A special optical fber cable with 3.2 mm outer diameter,produced by Brugg Kabel AG,was selected for the tests(V1 cable).

    After realization,the anchor was feld-installed in Campania Region,Italy.Distributed strain measurements were taken at each loading step.The results are summarized in Figs.10 and 11.Note that the symmetrical appearance of the various strain profles is due to the fact that the same fber was running twice along the cable.We observe a number of signifcant features:(a)the strain decreases linearly from the ground level,vanishing at the deepest end of the cable:this means that the whole cable length is involved in transferring the pullout force into the soil;(b)at larger displacement steps,the strain profle propagates behind the fxationpoint due toslippage of the glass fber inside the protection;(c) comparing Figs.10 and 11,it is seen that there is a signifcant residual strain along the fber at the end of the pullout test:for example,during the unloading phase a load of 100 kN produces a maximum strain of about 1000με,equivalent to the strain observed during the loading phase for a load of 350 kN.

    Fig.8.Test site in Basilicata Region,Italy.S9F:fber optic inclinometer;I9B,I9C: traditional inclinometers.

    Fig.7.Comparison between the displacements provided by the optical fber sensor (solid lines)and the ones provided by the dial gauges(squares).δrepresents the maximum displacement applied at the free end.

    6.Conclusions

    Fig.9.Displacement of the optical fber inclinometer(FOI-S9F)as a function of depth, and comparison with the readings of two traditional inclinometers:the I9B(depth: 27 m)and the I9C(depth:15 m)(after Minardo et al.,2014).

    Different applications of BOTDA based optical fber distributed sensors to geotechnical monitoring have been reported.Laboratoryand feld tests have shown the great potentialities of such sensors in monitoring and analyzing soil slopes and foundations.The main limitations of the proposed technology in geotechnical monitoring are essentially the lack of standardized procedures for sensing cables installation in large areas,the diffculty in data interpretation and accurate modeling of ground/sensor interaction.

    Fig.10.Strain measurements during the loading phase.

    Fig.11.Strain measurements during the unloading phase.

    Confict of interest

    The authors wish to confrm that there are no known conficts of interest associated with this publication and there has been no signifcant fnancial support for this work that could have infuenced its outcome.

    Acknowledgments

    It is gratefully noted that the project is supported by grant from MIUR-PON01 1525-MONICA.

    Boyd RW.Nonlinear optics.3rd ed.Waltham,Massachusetts,USA:Academic Press; 2008.

    Dewynter V,Rougeault S,Magne S,Ferdinand P,Vallon F,Avallone L,Vacher E,De Broissia M,Ch Canepa,Poulain A.Brillouin optical fber distributed sensor for settlement monitoring while tunneling the metro line 3 in Cairo,Egypt.In: Proceedings of the SPIE 7503,20th International Conference on Optical Fibre Sensors,75035M;2009.http://dx.doi.org/10.1117/12.835376.

    Iten M.Novel applications of distributed fber-optic sensing in geotechnical engineering.Zurich,Switzerland:vdf Hochschulverlag AG;2011.

    Lenke P,Wendt M,Krebber K,Gl?tzl R.Highly sensitive fber optic inclinometer: easy to transport and easy to install.In:Proceedings of the SPIE 7753,21st International Conference on Optical Fiber Sensors,775352;2011.http:// dx.doi.org/10.1117/12.884695.

    Minardo A,Bernini R,Amato L,Zeni L.Bridge monitoring using Brillouin fber-optic sensors.IEEE Sensor Journal 2012;12(1):145-50.

    Minardo A,Picarelli L,Avolio B,Coscetta A,Papa R,Zeni G,Di Maio C,Vassallo R, Zeni L.Fiber optic based inclinometer for remote monitoring of landslides:on site comparison with traditional inclinometers.In:Proceedings of International Geoscience and Remote Sensing Symposium(IGARSS 2014)/35th Canadian Symposium on Remote Sensing(35th CSRS),Québec City,Québec,Canada; 2014.p.4078-81.

    Olivares L,Damiano E,Picarelli L,Greco R,Bernini R,Minardo A,Zeni L.An instrumented fume for investigation of the mechanics of rainfall-induced landslidesinunsaturatedgranularsoils.GeotechnicalTestingJournal 2009;32(2):108-18.

    Pirone M,Damiano E,Picarelli L,Olivares L,Urciuoli G.Groundwater-atmosphere interaction in unsaturated pyroclastic slopes at two sites in Italy.Rivista Italiana di Geotecnica 2012;3:29-49.

    Luigi Zeniis full professor of electronics and photonics at the Second University of Naples and president of the Research Consortium on Advanced Remote Sensing Systems-CO.RI.S.T.A.(www.corista.eu).He has been,from 2001 to 2012,vice-director of the Department of Information Engineering.He took his degree in Electronic Engineering,summa cum laude,from University of Naples in 1988 and his Ph.D.in Electronics and Computer Science in 1992.He worked at TU-DELFT(NL)as a visiting scientist. He has been national coordinator of PRIN projects,scientifc coordinator of research contracts with public and private institutions and responsible for projects funded within the 7th FP of the EU.He has been member of the Management Committee of the COST 299“Optical fbers for new challenges facing the information society”and of the COST TD1001“Novel and Reliable Optical Fiber Sensor Systems for Future Security and Safety Applications”. His main research interests include optical fber sensors for distributed measurements of deformation and temperature,optoelectronic integrated sensors and biosensors.He is author of about 120 papers published in international journals,120 publications at international conferences and 10 patents.He is also founder of the Spin-Off company OPTOSENSING dealing with structural and environmental monitoring by optical fber sensors.

    *Corresponding author.Tel.:+39 0815010269.

    E-mail address:luigi.zeni@unina2.it(L.Zeni).

    Peer review under responsibility of Institute of Rock and Soil Mechanics,Chinese Academy of Sciences.

    1674-7755?2015 Institute of Rock and Soil Mechanics,Chinese Academy of Sciences.Production and hosting by Elsevier B.V.All rights reserved.

    http://dx.doi.org/10.1016/j.jrmge.2015.01.008

    好男人在线观看高清免费视频| 国产精品免费一区二区三区在线| 少妇被粗大猛烈的视频| 男人舔女人下体高潮全视频| 村上凉子中文字幕在线| 网址你懂的国产日韩在线| 婷婷精品国产亚洲av| 精品一区二区三区视频在线观看免费| 12—13女人毛片做爰片一| 日本-黄色视频高清免费观看| av中文乱码字幕在线| 一进一出好大好爽视频| 18禁裸乳无遮挡免费网站照片| 成年免费大片在线观看| 91在线观看av| 亚洲真实伦在线观看| 久久久久久久久久黄片| 欧美黑人巨大hd| 桃色一区二区三区在线观看| 在线播放无遮挡| 欧美一区二区精品小视频在线| 久久久久久伊人网av| 欧美在线一区亚洲| 亚洲国产精品久久男人天堂| 九九在线视频观看精品| 亚洲av美国av| 亚洲欧美日韩高清专用| 成人欧美大片| 亚洲 国产 在线| 国产国拍精品亚洲av在线观看| 午夜福利视频1000在线观看| 日本在线视频免费播放| 免费无遮挡裸体视频| 村上凉子中文字幕在线| 亚洲国产精品成人综合色| 老司机福利观看| 亚洲,欧美,日韩| 婷婷精品国产亚洲av在线| 少妇的逼好多水| 99久久精品国产国产毛片| 直男gayav资源| 国产黄片美女视频| 我的女老师完整版在线观看| 久久午夜亚洲精品久久| 成人一区二区视频在线观看| 人人妻人人澡欧美一区二区| 免费看美女性在线毛片视频| 热99re8久久精品国产| 亚洲av成人精品一区久久| 国产视频一区二区在线看| 婷婷六月久久综合丁香| 亚洲av免费高清在线观看| 亚洲精品乱码久久久v下载方式| 欧美激情久久久久久爽电影| 一进一出好大好爽视频| 精品一区二区三区视频在线| 18+在线观看网站| 成人国产一区最新在线观看| 午夜亚洲福利在线播放| 成年女人毛片免费观看观看9| 搡老熟女国产l中国老女人| 男人舔奶头视频| 久久精品综合一区二区三区| 干丝袜人妻中文字幕| 中国美白少妇内射xxxbb| av中文乱码字幕在线| 欧美性猛交╳xxx乱大交人| 99精品久久久久人妻精品| 成人一区二区视频在线观看| 精品久久久久久,| 免费大片18禁| 精品午夜福利视频在线观看一区| 少妇高潮的动态图| 99热只有精品国产| 午夜爱爱视频在线播放| 欧美+日韩+精品| 色在线成人网| 午夜亚洲福利在线播放| 久久精品国产鲁丝片午夜精品 | 九色成人免费人妻av| 久久久色成人| 国产探花在线观看一区二区| 午夜免费成人在线视频| av视频在线观看入口| 99久国产av精品| 天天一区二区日本电影三级| 一进一出好大好爽视频| 亚洲欧美日韩高清专用| 伦精品一区二区三区| 亚洲国产精品sss在线观看| 午夜亚洲福利在线播放| 老师上课跳d突然被开到最大视频| 日本成人三级电影网站| 国产av不卡久久| 国产真实乱freesex| 看片在线看免费视频| 日韩一本色道免费dvd| 久久久久久久午夜电影| 一级av片app| 亚洲va日本ⅴa欧美va伊人久久| 亚洲精品成人久久久久久| 亚洲国产精品成人综合色| 日本在线视频免费播放| 国产精品久久久久久久电影| 欧美精品国产亚洲| 麻豆精品久久久久久蜜桃| 国产伦在线观看视频一区| 国产三级在线视频| 99国产精品一区二区蜜桃av| 男女那种视频在线观看| 一区二区三区高清视频在线| 一个人免费在线观看电影| 亚洲av电影不卡..在线观看| 国产黄片美女视频| 精品乱码久久久久久99久播| 日韩 亚洲 欧美在线| 中文字幕av在线有码专区| 我的老师免费观看完整版| 日本精品一区二区三区蜜桃| av视频在线观看入口| 色精品久久人妻99蜜桃| 国产精品一区二区三区四区免费观看 | 久久久久精品国产欧美久久久| 精品99又大又爽又粗少妇毛片 | 免费av毛片视频| eeuss影院久久| 午夜影院日韩av| 久久久午夜欧美精品| 在线观看av片永久免费下载| 亚洲第一区二区三区不卡| 成年版毛片免费区| 黄色配什么色好看| 国产伦一二天堂av在线观看| 亚洲av中文字字幕乱码综合| 99热这里只有是精品50| 欧洲精品卡2卡3卡4卡5卡区| 欧美成人免费av一区二区三区| 99热这里只有是精品在线观看| 精品人妻熟女av久视频| 成人av在线播放网站| 亚洲av免费高清在线观看| videossex国产| 亚洲精华国产精华精| 久久久久久久精品吃奶| 天美传媒精品一区二区| 欧美一区二区亚洲| 国产一区二区亚洲精品在线观看| 亚洲国产欧洲综合997久久,| 国产精品国产三级国产av玫瑰| 国产精品av视频在线免费观看| 村上凉子中文字幕在线| 神马国产精品三级电影在线观看| 一进一出抽搐gif免费好疼| 免费观看在线日韩| 亚洲成人免费电影在线观看| 九九在线视频观看精品| 熟女电影av网| 亚洲色图av天堂| 老熟妇乱子伦视频在线观看| 老熟妇乱子伦视频在线观看| 看十八女毛片水多多多| 一个人看的www免费观看视频| 国产蜜桃级精品一区二区三区| 日韩中字成人| 亚洲精品日韩av片在线观看| 成人特级av手机在线观看| 亚洲七黄色美女视频| 亚洲欧美清纯卡通| 乱系列少妇在线播放| 久久国产精品人妻蜜桃| 99久久九九国产精品国产免费| 午夜福利欧美成人| 在线观看美女被高潮喷水网站| 久久99热6这里只有精品| 韩国av一区二区三区四区| 又粗又爽又猛毛片免费看| 亚洲精品色激情综合| 国产成人福利小说| 亚洲av免费在线观看| 亚洲精品粉嫩美女一区| 国国产精品蜜臀av免费| 中文字幕熟女人妻在线| 少妇裸体淫交视频免费看高清| 丝袜美腿在线中文| 在线观看午夜福利视频| 能在线免费观看的黄片| 久久久久性生活片| 如何舔出高潮| 别揉我奶头 嗯啊视频| 国产综合懂色| 天堂网av新在线| 国产精品99久久久久久久久| 欧美激情久久久久久爽电影| 99久久九九国产精品国产免费| 永久网站在线| 在线观看av片永久免费下载| 成人特级黄色片久久久久久久| av在线亚洲专区| av在线老鸭窝| АⅤ资源中文在线天堂| 日韩,欧美,国产一区二区三区 | 99riav亚洲国产免费| 亚洲久久久久久中文字幕| 日韩,欧美,国产一区二区三区 | 极品教师在线免费播放| 国产日本99.免费观看| 国产在线男女| 一区二区三区高清视频在线| 国产av不卡久久| 午夜精品在线福利| 亚洲在线自拍视频| 神马国产精品三级电影在线观看| 国产亚洲av嫩草精品影院| 色综合婷婷激情| 99久久精品热视频| 免费看日本二区| 国产视频一区二区在线看| 国产精品爽爽va在线观看网站| 校园春色视频在线观看| 免费看a级黄色片| 国产高清有码在线观看视频| 蜜桃亚洲精品一区二区三区| 精品国内亚洲2022精品成人| 久久久色成人| 特大巨黑吊av在线直播| 国产欧美日韩精品一区二区| 亚洲久久久久久中文字幕| 久久精品国产亚洲av涩爱 | 国产一区二区三区视频了| 日韩中字成人| 岛国在线免费视频观看| 久久草成人影院| 白带黄色成豆腐渣| 丰满的人妻完整版| 禁无遮挡网站| 亚洲av成人精品一区久久| 欧美区成人在线视频| 他把我摸到了高潮在线观看| 国产精品久久视频播放| 日日夜夜操网爽| 中文字幕av成人在线电影| 亚洲最大成人av| 美女高潮的动态| 欧美不卡视频在线免费观看| 久久亚洲精品不卡| 18禁裸乳无遮挡免费网站照片| 国产激情偷乱视频一区二区| 国产午夜精品久久久久久一区二区三区 | 少妇的逼水好多| 日本五十路高清| 欧美zozozo另类| 亚洲天堂国产精品一区在线| 在线天堂最新版资源| 十八禁网站免费在线| 亚洲最大成人手机在线| 国产成人a区在线观看| 在线观看免费视频日本深夜| 九九久久精品国产亚洲av麻豆| 亚洲国产精品成人综合色| 蜜桃久久精品国产亚洲av| 国产精品亚洲一级av第二区| 国产亚洲91精品色在线| 一本一本综合久久| 国产伦精品一区二区三区四那| 亚洲成人精品中文字幕电影| 69av精品久久久久久| 直男gayav资源| 免费观看在线日韩| 中文字幕熟女人妻在线| 男人狂女人下面高潮的视频| 中国美白少妇内射xxxbb| 国产真实伦视频高清在线观看 | 男女那种视频在线观看| 欧美不卡视频在线免费观看| 日本在线视频免费播放| 亚洲色图av天堂| 成人国产麻豆网| 日本 欧美在线| 欧美最黄视频在线播放免费| 久久精品人妻少妇| 久久精品综合一区二区三区| 中出人妻视频一区二区| 欧美精品啪啪一区二区三区| 美女免费视频网站| 午夜亚洲福利在线播放| 亚洲美女搞黄在线观看 | 赤兔流量卡办理| 悠悠久久av| 亚洲最大成人av| 亚洲欧美精品综合久久99| 日本熟妇午夜| 欧美+亚洲+日韩+国产| 亚洲无线在线观看| 欧美成人性av电影在线观看| 亚洲人与动物交配视频| 午夜久久久久精精品| 国产高清不卡午夜福利| 亚洲av免费在线观看| 午夜爱爱视频在线播放| 亚洲三级黄色毛片| 国产av在哪里看| 两个人视频免费观看高清| 91精品国产九色| 搞女人的毛片| 亚洲真实伦在线观看| 超碰av人人做人人爽久久| 色尼玛亚洲综合影院| 国产高潮美女av| 免费看美女性在线毛片视频| 亚洲第一电影网av| 色哟哟哟哟哟哟| 日韩欧美免费精品| 久久精品国产鲁丝片午夜精品 | 亚洲va在线va天堂va国产| 亚洲中文日韩欧美视频| 午夜a级毛片| 国产淫片久久久久久久久| 免费看光身美女| 十八禁网站免费在线| 两人在一起打扑克的视频| 又紧又爽又黄一区二区| 综合色av麻豆| 欧洲精品卡2卡3卡4卡5卡区| ponron亚洲| 亚洲av熟女| 国产激情偷乱视频一区二区| 久久精品夜夜夜夜夜久久蜜豆| 久久精品国产自在天天线| 床上黄色一级片| 亚洲精品456在线播放app | 国内毛片毛片毛片毛片毛片| 国产精品一区二区免费欧美| 午夜福利18| 国产精品嫩草影院av在线观看 | 村上凉子中文字幕在线| 亚洲自偷自拍三级| 精品日产1卡2卡| 日本黄大片高清| 免费高清视频大片| 久久午夜福利片| 久久久久免费精品人妻一区二区| 国产真实伦视频高清在线观看 | 国产高潮美女av| 欧美zozozo另类| 亚洲中文日韩欧美视频| 久久婷婷人人爽人人干人人爱| 色视频www国产| h日本视频在线播放| 露出奶头的视频| 欧美另类亚洲清纯唯美| 人人妻,人人澡人人爽秒播| 国产亚洲精品久久久com| 色综合婷婷激情| 久久久久久伊人网av| 99热6这里只有精品| 国产高清不卡午夜福利| 听说在线观看完整版免费高清| 乱码一卡2卡4卡精品| 91av网一区二区| 国产欧美日韩一区二区精品| 国产精品乱码一区二三区的特点| 国产亚洲91精品色在线| 亚洲av不卡在线观看| 国产免费一级a男人的天堂| 深爱激情五月婷婷| 人妻久久中文字幕网| 国产一级毛片七仙女欲春2| 18禁在线播放成人免费| 亚洲男人的天堂狠狠| 国产精品一区二区性色av| 最近中文字幕高清免费大全6 | 国产免费一级a男人的天堂| 国产精品久久久久久av不卡| 欧美日本视频| 黄色女人牲交| 97超级碰碰碰精品色视频在线观看| 婷婷精品国产亚洲av| 我要看日韩黄色一级片| 亚洲在线观看片| 国产三级在线视频| 嫁个100分男人电影在线观看| 亚洲精华国产精华液的使用体验 | 日日撸夜夜添| 中文字幕熟女人妻在线| 国产又黄又爽又无遮挡在线| 国产真实伦视频高清在线观看 | 人人妻人人看人人澡| 婷婷色综合大香蕉| 欧美在线一区亚洲| 直男gayav资源| 91av网一区二区| 99精品久久久久人妻精品| 婷婷亚洲欧美| www.色视频.com| 一本一本综合久久| 久久久久国产精品人妻aⅴ院| 麻豆国产97在线/欧美| 日本在线视频免费播放| 午夜福利在线在线| 最后的刺客免费高清国语| 国产午夜精品论理片| 九色成人免费人妻av| 日本在线视频免费播放| 亚洲精品一区av在线观看| 免费观看的影片在线观看| 搞女人的毛片| 亚洲内射少妇av| 蜜桃久久精品国产亚洲av| 国产男靠女视频免费网站| 美女cb高潮喷水在线观看| 不卡视频在线观看欧美| 国产欧美日韩精品亚洲av| 别揉我奶头 嗯啊视频| 69人妻影院| 欧美中文日本在线观看视频| 午夜福利在线观看免费完整高清在 | 日日摸夜夜添夜夜添小说| 日韩一本色道免费dvd| 淫秽高清视频在线观看| 一级黄片播放器| 欧美激情久久久久久爽电影| 国产亚洲91精品色在线| 国产久久久一区二区三区| 欧美日本亚洲视频在线播放| 亚洲av免费高清在线观看| 亚洲av二区三区四区| 极品教师在线免费播放| 人妻丰满熟妇av一区二区三区| 久久精品夜夜夜夜夜久久蜜豆| 国产视频内射| 国产爱豆传媒在线观看| 亚洲欧美清纯卡通| 人妻制服诱惑在线中文字幕| 国国产精品蜜臀av免费| 九色国产91popny在线| 一a级毛片在线观看| 久久99热6这里只有精品| 一区二区三区高清视频在线| 美女cb高潮喷水在线观看| 网址你懂的国产日韩在线| 日韩高清综合在线| 国内少妇人妻偷人精品xxx网站| 很黄的视频免费| 亚洲成人精品中文字幕电影| 国内久久婷婷六月综合欲色啪| 国产私拍福利视频在线观看| 国产伦精品一区二区三区四那| 黄色视频,在线免费观看| 看免费成人av毛片| 一本久久中文字幕| 欧美+亚洲+日韩+国产| 成人鲁丝片一二三区免费| 男人舔女人下体高潮全视频| 亚洲人成网站高清观看| 国产精品爽爽va在线观看网站| 久久精品国产亚洲av涩爱 | a级毛片a级免费在线| 日韩欧美在线乱码| 亚洲国产精品成人综合色| av天堂中文字幕网| 亚洲欧美日韩高清专用| 最好的美女福利视频网| 一级av片app| 精品一区二区免费观看| 午夜福利在线观看吧| 国产精品1区2区在线观看.| 国产精华一区二区三区| 成人国产一区最新在线观看| 亚洲av不卡在线观看| 高清日韩中文字幕在线| a级一级毛片免费在线观看| 日韩强制内射视频| 白带黄色成豆腐渣| 99在线视频只有这里精品首页| 日本五十路高清| 国产精品久久电影中文字幕| 国产国拍精品亚洲av在线观看| 中文资源天堂在线| 中亚洲国语对白在线视频| 1000部很黄的大片| 久久久国产成人精品二区| 国产精品久久久久久精品电影| 免费人成在线观看视频色| 超碰av人人做人人爽久久| 免费av不卡在线播放| 久久久色成人| 精品久久久久久,| 精品人妻一区二区三区麻豆 | 一区二区三区四区激情视频 | 欧美激情久久久久久爽电影| 国内精品宾馆在线| 亚洲乱码一区二区免费版| 色尼玛亚洲综合影院| 国产成人福利小说| 看免费成人av毛片| 国产精品嫩草影院av在线观看 | 成人av在线播放网站| 亚洲国产精品sss在线观看| 国产在视频线在精品| 国产黄a三级三级三级人| 亚洲性久久影院| 在线观看午夜福利视频| 日韩欧美国产一区二区入口| 亚洲avbb在线观看| 亚洲内射少妇av| 老司机深夜福利视频在线观看| 久久天躁狠狠躁夜夜2o2o| 一进一出抽搐gif免费好疼| 国产精品久久久久久久久免| 丰满人妻一区二区三区视频av| 日韩欧美在线乱码| 午夜福利在线观看吧| 又粗又爽又猛毛片免费看| 亚洲avbb在线观看| 国产一区二区在线av高清观看| 伊人久久精品亚洲午夜| 在现免费观看毛片| 一级a爱片免费观看的视频| 亚洲人成网站高清观看| 一个人免费在线观看电影| 国产视频一区二区在线看| 热99re8久久精品国产| 国产主播在线观看一区二区| 成人一区二区视频在线观看| 久久久久久久精品吃奶| 欧美一区二区精品小视频在线| 人妻久久中文字幕网| 久久精品影院6| 日本熟妇午夜| 99在线视频只有这里精品首页| 97人妻精品一区二区三区麻豆| 真实男女啪啪啪动态图| 制服丝袜大香蕉在线| 夜夜看夜夜爽夜夜摸| 日本黄色片子视频| 美女黄网站色视频| 久久久久久久久久成人| 午夜免费激情av| 婷婷精品国产亚洲av在线| 精品人妻一区二区三区麻豆 | 午夜福利在线观看吧| 男人舔奶头视频| 日本在线视频免费播放| 狂野欧美激情性xxxx在线观看| 变态另类成人亚洲欧美熟女| 三级毛片av免费| 日韩欧美一区二区三区在线观看| 欧美高清成人免费视频www| 国模一区二区三区四区视频| av中文乱码字幕在线| 国产综合懂色| 制服丝袜大香蕉在线| 亚洲第一区二区三区不卡| 国产精品伦人一区二区| 国产国拍精品亚洲av在线观看| 亚洲国产精品合色在线| 可以在线观看的亚洲视频| 国产不卡一卡二| 大又大粗又爽又黄少妇毛片口| 国内毛片毛片毛片毛片毛片| 999久久久精品免费观看国产| 干丝袜人妻中文字幕| 国产高清视频在线观看网站| 久久精品国产亚洲av涩爱 | 国产成人影院久久av| 亚洲美女黄片视频| 欧美一级a爱片免费观看看| 狠狠狠狠99中文字幕| 我的老师免费观看完整版| 中文字幕免费在线视频6| 精品久久国产蜜桃| 国产精品1区2区在线观看.| 在线看三级毛片| 免费不卡的大黄色大毛片视频在线观看 | 少妇熟女aⅴ在线视频| 成人性生交大片免费视频hd| 九九久久精品国产亚洲av麻豆| 亚洲精华国产精华液的使用体验 | 久久久久久久精品吃奶| 欧美+亚洲+日韩+国产| 亚洲天堂国产精品一区在线| 一个人免费在线观看电影| 国产高潮美女av| 欧美国产日韩亚洲一区| 亚洲狠狠婷婷综合久久图片| 欧美三级亚洲精品| 成人亚洲精品av一区二区| 亚洲国产欧美人成| 99视频精品全部免费 在线| 国产单亲对白刺激| 国产精品三级大全| 在线观看免费视频日本深夜| 亚洲精品456在线播放app | 看免费成人av毛片| 无人区码免费观看不卡| 国产精品,欧美在线| 成人高潮视频无遮挡免费网站| 成人av在线播放网站| 免费av毛片视频| 国产探花极品一区二区| 日韩 亚洲 欧美在线| 色吧在线观看| 少妇熟女aⅴ在线视频| 无人区码免费观看不卡| 免费不卡的大黄色大毛片视频在线观看 | 热99在线观看视频| 韩国av一区二区三区四区| 亚洲欧美日韩高清专用| 国产精品av视频在线免费观看| 搡老熟女国产l中国老女人| 毛片女人毛片| 久久亚洲精品不卡| 国产精品亚洲美女久久久| 久99久视频精品免费| 美女黄网站色视频|