The 12th International Symposium on Structural Engineering PERCEPTION EFFECT ANALYSIS OF SMART POT RUBBER BEARING UNDER VERTICAL LOAD Bin Huang, Yonghui Feng, Roohollah Fallahi Seresh, Xingqi Song School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, P.R. China Abstract : On the basis of traditional pot rubber bearing, optical fiber strain sensor is introduced to design a type of new pressure sensor, which is able to measure the vertical load of the pot rubber bearing. In this paper, by using ANSYS software, a three-dimensional finite element model of the new pot rubber bearing with smart perception ability is established. Then the load-strain relationship of measuring force steel sheets as well as the arrangement position of optical fiber sensors are studied through numerical analysis. Finally, a full-scale test of a designed bearing is completed. The test results show that the linear fitting degree between the vertical load and the fiber strain is very well, and the sensitivity of load to optic fiber strain in the test is almost the same as that of the numerical simulation. All of these illustrate that the designed smart pot rubber bearing is capable of correctly percept the vertical load of the bearing automatically and timely. Keywords: Pot rubber bearing, optical fiber strain sensor, vertical load, measuring force steel sheet, load-strain relationship Pot rubber bearing not only has a large bearing capacity, flexible rotation and a large range of horizontal deformation, but also possesses the characteristics of structural simpleness, small height, and economy. Because of these advantages, currently it is being used in bridge constructions and other building structures (such as the support points of large roofs) as shown in the work by Shen et al.(2003)and Lizuka(2000) . In practical engineering, it is worth for us to pay close attention to the variation of using performance and carrying capacity of these bearings. Particularly, it is expected to have a record of the change history of the bridge vertical load and traffic flow by real-time monitoring of the bearing load. Furthermore, these information are able to be employed to evaluate the safety of bearings and bridge as shown in the work by Liu and Wang(2009).Thus our aim could be reached if the bearings themselves have the ability to perceive their bearing capacity intelligently. Therefore, it becomes a key to develop a smart bearing with self-perception in the process of achieving this goal. As we know, for the traditional pot rubber bearings, it is difficult to measure the stress and strain of the basin edge by instruments effectively. Now we designed a fiber optic sensor system that has the capability to perceive the upper bearing capacity exclusively. In the process of realizing the design, some specific measures are taken so that the local strain of the measuring force steel sheet increases to the measurable range. In this article, a three-dimensional finite element numerical simulation about the sensor system is studied. Then the numerical simulation is used to predict the relationship of vertical load and local strain, and a full scale test is carried out to verify the results of numerical simulation. After all of these, a smart pot rubber bearing is made, which can be used to monitor the load of the bridge superstructure. By this type of smart pot rubber bearing, the load flow of the bridge superstructure can be detected, even the structural health status is able to be evaluated. 1 DESIGN OF SMART POT RUBBER BEARING The smart pots rubber bearing that we refer to is composed of slotted traditional pot rubber bearing, measuring force steel sheets, fiber-optic strain gauge sensors as well as measurement system. Now GPZ(II) 2.5GD model, which was produced in Liuzhou Oriental rubber factory in Guangxi, is selected as the traditional pot rubber
