【作者】 谭晓晶；

【导师】 吴斌；

【作者基本信息】 哈尔滨工业大学 ， 防灾减灾工程及防护工程， 2013， 博士

【摘要】 拟动力试验是评价和研究结构抗震性能的重要手段。随着经济和科技的发展，现代工程结构越来越趋向于大型化和复杂化。传统的缩尺模型试验已经难以满足科学研究与工程实际的需要，大比例尺甚至足尺模型试验日益受到重视，因而试件的刚度也往往比较大。在拟动力试验中，电液伺服作动器常采用位移控制工作模式。但是由于作动器自身的位移控制分辨率有限，在进行大刚度试件的位移控制加载时，将难以完成小位移命令的控制加载，得到的拟动力试验结果不可靠。因此，开展大刚度试件的拟动力试验方法研究是十分必要的，这对丰富和完善传统结构抗震试验方法具有重要意义。本文以大刚度试件为研究对象，针对大刚度试件的拟动力试验方法开展研究，主要研究工作及成果如下：（1）为了能清晰地界定大刚度试件的范畴，从试验角度出发提出了大刚度试件的判别公式，为试验方案的合理制定提供依据。设计制作了一个单层单开间的足尺砖混结构模型用以模拟一个单层十个开间的原型结构。首先对该模型所用的材料进行了力学性能试验，然后进行了该试验模型在大震激励下的拟动力试验，用来揭示该类型结构的抗震性能。试验结果表明该类型结构具有很好的抗震性能，要超出我国抗震规范中“大震不倒”的设防目标。最后对该模型在小震激励下的拟动力试验进行数值模拟，结果表明采用位移控制加载的试验方法将难以完成此大刚度模型在小震激励下的拟动力试验。（2）进行了小位移命令的控制加载试验，进一步阐述了位移控制加载方法存在的问题。为此，提出了位移与力混合控制的拟动力试验方法，该方法引入了外置的高精度位移传感器来弥补作动器自身位移控制分辨率不足的缺点。首先分析了该方法中的比例-积分位移控制器的稳定条件和稳态误差，然后介绍了位移控制器参数的实用设计方法，最后从数值模拟和试验验证的角度阐述了该方法的可行性和有效性。研究表明，该方法可以很好地解决大刚度试件位移控制加载存在的问题。（3）由于大刚度试件的反力通常会较大，电液伺服作动器更适合采用力控制加载模式。鉴于此，提出了基于力控制加载的等效力控制方法。等效力控制方法是一种基于隐式积分方法的采用力反馈控制代替数值迭代的拟动力试验方法。首先分析了采用比例-积分等效力控制器时等效力控制回路的稳定条件和稳态误差，然后从数值模拟和真实试验验证了该方法的可行性和有效性。结果表明，对于大刚度试件该方法要优于基于位移控制的等效力控制方法。（4）为了融合力控制模式和位移控制模式的优点，并在拟动力试验中实现两种模式的自动切换，提出了基于位移正反馈的力与位移切换控制方法。首先从理论角度分析了切换控制过程，然后从数值模拟和试验角度验证了该方法的可行性和有效性。研究结果表明，该方法能很好地实现力与位移控制模式之间自动而平滑的切换，可以应用到大刚度试件拟动力试验中。更多还原

【Abstract】 Pseudo-dynamic (PSD) testing is an important tool to evaluate and studyseismic performance of structures. With the development of economy andtechnology, modern engineering structures become much larger and more complexand the traditional scaled model tests cannot satisfy the needs of the scientificresearch and engineering applications any more. Therefore, large-scale evenfull-scale model tests have obtained increasingly attention in structural experimentalengineering, in which the stiffness of the test specimen is usually very large.However, owing to the limited resolution of the displacement control of the actuator,it may be difficult to impose small displacement commands on large stiffnessspecimens in displacement control, and hence reliable PSD test results are also hardto attain. Thus, it is necessary to study the PSD testing method for the large stiffnessspecimens, which is of great significance in enriching and improving the traditionalseismic test methods.This study focuses on problems of PSD testing for large stiffness specimens.Main work and finding are as follows:1. A discriminate formula defining the range of large stiffness specimens isproposed from the view point of tests, which can be used to establish a reasonabletest plan. A full-scale single-storey single-bay masonry model is fabricated tosimulate a single-layer ten-bay original structure. At first, the mechanical propertytest of the structural material is carried out. Then, the PSD test of this model underlarge earthquake excitation is performed to explore its seismic performance. Resultsshow that this kind of structures has excellent seismic behavior that greatly exceedsthe seismic precautionary criterion under the rare earthquake attack of our country.Finally, numerical simulations of the PSD test of this model are performed. Resultsshow that PSD tests of large stiffness specimens under small earthquake excitationwith displacement control is difficult to accomplish.2. In order to clearly further demonstrate difficulties in displacement control,loading tests of small displacements are carried out. A mixed displacement-forcecontrol method is presented, which brings a high-resolution sensor into thedisplacement control loop to circumvent insufficient accuracy of the loading devices.The stability and steady state error of this method with a proportional-integraldisplacement controller are analyzed, and then a practical method for designingparameters of the displacement controller is introduced. Finally, the feasibility andeffectiveness of this method for tests of large stiffness specimens is verified by numerical simulations and real experiments. Research shows that this particularapproach can well resolve problems in displacement control of large stiffnessspecimens.3. The reaction force of large stiffness specimens is usually larger even at asmall displacement response and thus force control mode is more suitable forhydraulic-servo actuators. For this reason, force control mode of actuators isproposed to incorporate to the equivalent force (EF) control method, which is a PSDmethod based on an implicit integration algorithm replacing numerical iteration withforce feedback control. The stability condition and steady state error of the outerloop with a proportion-integration EF controller are analyzed. Numericalsimulations and real experiments are performed to verify the feasibility andeffectiveness of this method. Results show that this method is superior to the EFcontrol method with displacement control of actuators.4. A force-displacement switching control method based on the positivedisplacement feedback loop is proposed in order to combine the advantages of theforce control mode and the displacement control mode and to accomplish automaticswitching in PSD. Firstly, the switching process is theoretically analyzed. Numericalsimulations and test results demonstrate that this method can provide automatic andsmooth switching between force control and displacement control, which can bewell applied to the PSD with large stiffness specimens.更多还原