專業(yè)英語不均勻沉降 混凝土路面 應(yīng)力應(yīng)變監(jiān)測

1、Strain Monitoring of Widening Cement Concrete Pavement Subjected to Differential Settlement of Foundation地基不均勻沉降下的寬混凝土路面的地基不均勻沉降下的寬混凝土路面的應(yīng)力應(yīng)變監(jiān)測應(yīng)力應(yīng)變監(jiān)測CatalogvAbstract vKeywords vBackground vMain Content vResults and DiscussionvReferences Abstract vThis paper describes the use of a sensor based on a f

2、iber Bragg grating (FBG), which is capable of reducing strain transfer errors, to measure the strain features within the top and bottom layers of a cement concrete pavement subject to different degrees of foundation settlement. Based on measured data, the characteristics of the distribution and the

3、variation in the structure strain were analyzed in detail. v本文介紹了基于光纖光柵原理的一種傳感器，這種傳感器能夠減少應(yīng)變傳遞誤差，并測量頂層和底層受不同程度的基礎(chǔ)沉降影響的水泥混凝土路面的應(yīng)變功能。基于實測數(shù)據(jù)，詳細分析了該結(jié)構(gòu)應(yīng)變分布的特點及變化規(guī)律。vBy comparing the measured results with those obtained by means of finite element analysis, the proposed FBGbased sensor assembly was found to

4、 be capable of effectively monitoring the strain distribution in a cement concrete pavement,thus proving that the improved optical fiber grating strain sensor is a very promising solution for road pavement structural health monitoring.v 通過實測結(jié)果與有限元分析的方法比較，可以看出該光纖光柵傳感器組件是能夠有效地監(jiān)測的應(yīng)變分布在水泥混凝土路面，進一步也證明改進后

5、的光纖光柵應(yīng)變傳感器對于路面結(jié)構(gòu)健康監(jiān)測方面的研究是一種很有前景的解決方案。 Keywords vFBG; vSensors; vStrain Monitoring ; vCement Concrete Pavement;v Differential Settlement of Foundation; vThe main advantages of optical fiber sensors over conventional monitoring techniques include their immunity to electromagnetic interference, their

6、small size, and lightweight construction, which can overcome the limitations.Optical fiber technology has been widely used for structure monitoring in civil engineering. vMany road widening projects quickly saw the appearance of many longitudinal cracks, soon after the completion of construction. Th

7、erefore, research into road widening projects has very practical significance.Background vThis paper mainly describes the use of an FBG sensor to monitor the strain features of a concrete pavement structure in fullsize model testing. The paper is divided into two parts. In part 1, we present the phy

8、sical background to Bragg grating sensors and their application to full-size model tests. In part2, the results of experiments are presented and compared with those of finite-elements method (FEM) simulations.Background Main Content Bragg grating reflecting light wave with specific wavelength. When

9、a broadband light source is injected into the optical fiber, the FGB will reflect a part of narrow spectrum light with specific wavelength and then generate a certain reflection spectrum.The center wavelength of the reflected light has a specific relationship with the optical fiber strain and temper

10、ature. FBG sensor is also very sensitive to temperature change, so the temperature-compensation problem must be solved. During the test, by adding another temperature sensor, the temperature of the same field is measured, and then the test strain values would be modified.Main Content The main applic

11、ation difficulty originates in two areas.First one is the accurate installation and on-site protection of the fiber optic cable transmission grating. To allow the fiber grating to reflect the deformation, stress, and other physical values of the structure, it is necessary to ensure synchronization d

12、eformation between the fiber grating and the object. In addition, to accurately obtain the strain in the pavement structure and its variation with temperature, fiber grating readings must isolate strain and temperature in the process of long-term monitoring.Main Content The lift system of the model

13、test simulation platform consists of hydraulic jacks, which can simulate the settling values and the sedimentation rate of the foundations. The multiple rig panels of the test platform are assembled into a “ground surface” with manual control, while translational and rotational movements are achieve

14、d using the activities panel under the control of the lifting system, which can be approximated by simulating the actual surface foundation settlement. Main Content To effectively protect a sensor in hostile construction environments and thus attain reasonable monitoring data, a protection system ba

15、sed on a tube-package was developed and implemented. Main Content It can be seen that the strain gradually increases with the increase in . A relatively steady stage with small magnitude is observed before reaches 8 cm. When surpasses 8 cm,however, the strain begins to increase more rapidly. At this

16、 point, due to the additional stress caused by considerable differential settlement of the ground, structural failure develops in the pavement and cracking occurs on the surface.Main Content As shown in Figure 8, the strain data for Nodes 1 to 12 were observed, so as to obtain the strain curves for

17、the concrete pavement subjected to differential settlement of the foundation (Figure 9).Results and Discussion A comparison between the measured and FEA results showed that both results exhibit the same variations and trends, which show that the improved optical fiber grating strain sensor constitut

18、es a very promising solution for application to road pavement structural health monitoring, as well as other civil structures.References1 Y. B. Lin, C. L. Pan, Y. H. Kuo, K. C. Chang, and J. C. Chern,“Online monitoring of highway bridge construction using fiber Bragg grating sensors,” Smart Material

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23、itoring, vol. 14, no. 1, pp. 4656, 2015.References8 Z. Zhou, W. Liu, Y. Huang et al., “Optical fiber Bragg grating sensor assembly for 3D strain monitoring and its case study in highway pavement,” Mechanical Systems and Signal Processing,vol. 28, pp. 3649, 2012.9 Y. Chen, L. V. Yue, and Z. Zhang, “T

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