【作者】 郑雪梅；

【导师】 许国山；

【作者基本信息】 哈尔滨工业大学 ， 土木工程， 2018， 硕士

【摘要】 目前多用三自由度加载系统来模拟工程结构在各种情况下的地震反应。而随着结构试验试件的尺寸越来越大,边界条件越来越复杂,相应地对加载系统的精度要求也越来越高。三自由度加载试验通过其附属的MTS 793软件进行控制,当试验中相关参数发生变化时,MTS 793软件内部程序需要进行相应修改。因此,通过内置计算编辑器实现试验复杂且不方便。并且对于考虑几何非线性的力-位移混合控制方法,其计算能力有限。因此,本文的主要研究内容及结论如下:(1)完善与改进三自由度拟静力试验加载控制软件。利用该软件进行数值模拟,模拟结果表明:该软件的运行结果准确。将其与MTS 793软件对接,应用到实际试验中,试验结果表明:三自由度拟静力试验加载控制软件在实际试验控制中可靠性强,且操作简单方便。(2)利用控制软件进行三自由度拟静力试验验证竖向基于作动器反馈的力-位移混合控制方法的准确性。试验结果表明:试件实际的水平位移与目标水平位移有明显误差,试件实际转角与目标转角之间误差更加明显。竖向基于作动器反馈的力-位移混合控制方法不能准确地控制试验加载。(3)利用控制软件进行三自由度拟静力试验,验证了竖向基于LVDT反馈的力-位移混合控制方法的准确性。试验结果表明:该方法在采用变水平位移-定轴力-无转角命令时有效可行,但是当采用变水平位移-变轴力-变转角复杂命令时,水平位移误差仍较明显,有待改进。(4)利用控制软件进行三自由度拟静力试验,验证考虑几何非线性的力-位移混合控制方法的准确性。试验结果表明:该方法能够使得试件的实际反应较好地跟踪相应目标命令,误差最小,控制效果最好。更多还原

【Abstract】 At present,a three-degree-of-freedom loading system is often used to simulate the seismic response of engineering structures under various conditions.As the size of the structural test specimens becomes larger and larger,the boundary conditions become more and more complex,and the accuracy requirements of the loading system are correspondingly higher.The three-degree-of-freedom loading test is controlled by its affiliated MTS 793 software.The relevant parameters in the test change,and the internal program needs to be modified accordingly.Therefore,it is complicated and inconvenient to implement the test through the built-in calculation editor.And for the force-displacement mixed control method considering the geometric nonlinearity,its computational ability is limited.Therefore,the main research contents and conclusions of this paper are as follows:(1)Perfect and improve the three-degree-of-freedom quasi-static test loading control software.Use the software for numerical simulation,The simulation results show that: The results of the software are accurate.It is connected to the MTS 793 software and applied to the actual test to verify the reliability of the software.The test results show that: The three-degree-of-freedom quasi-static test loading control software has strong reliability in actual test control,and the operation is convenient and simple.(2)The three-degree-of-freedom quasi-static test was performed using the control software to verify the accuracy of the force-displacement mixed control(based on actuator feedback in the vertical direction)method based on the feedback of the external displacement sensors.The test results show that: The actual horizontal displacement of the specimen has a significant error with the target horizontal displacement.The error between the actual corner of the specimen and the target corner is more obvious.The force-displacement mixed control(based on actuator feedback in the vertical direction)method based on the feedback of the external displacement sensors does not allow the actual response of the specimen to track the corresponding target command well.(3)The three-degree-of-freedom quasi-static test was performed using the control software to verify the accuracy of the force-displacement mixed control(based on LVDT feedback in the vertical direction)method based on the feedback of the external displacement sensors.The test results show that: This method is effective and feasible when using the variable horizontal displacement fixed-axis force instruction with zero angle command.However,when the variable horizontal displacement variable axial force variable angle complex command is adopted,the error is still obvious,and the control of the horizontal displacement still needs to be improved.(4)The three-degree-of-freedom quasi-static test was performed using the control software to verify the accuracy of the force-displacement mixed control method considering the geometric nonlinearity.The test results show that: The method can make the actual reaction of the test piece track the corresponding target command well,with the smallest error and the best control effect.更多还原