A milling unbalance correction method based on a discrete vector model is proposed to address the issue of poor performance of traditional dynamic balancing methods when the initial unbalance of the micro motor rotor is large. A discrete vector model is established based on the parameters of the milling cutter and rotor，and the corresponding relationship between the equivalent cutting mass and cutting depth under second time cutting is obtained by integrating the discrete points of the edge curve. By comparing with the 3D model simulation data，it is verified that the deviation rate of the model is low. Experimental verification shows that when the initial unbalance on one side of the rotor exceeds 100 mg，a total weight removal rate of over 90% can be achieved，and the equivalent mass of the remaining unbalance on one side can be controlled below 10 mg. All rotors meet the G1 accuracy level. This indicates that this proposed method can improve the dynamic balance accuracy of the micro motor rotor when the initial unbalance of the micro motor rotor is large.

Active magnetic bearings （AMBs） are ideal bearings for high speed and high power rotating machinery for its adjustable stiffness and damp. In this paper，a dynamic model of AMBs-flexible rotor system is established. Aiming at suppressing vibration displacement of the rotor system in passing through the first bending critical speed region，a control which combines a decentralized PID controller and input second filter in series is designed and the controller performances are simulated. The experiments in simulated rotation and real acceleration operations are carried out in a platform of AMBs-flexible rotor system. The rotor system can smoothly pass through its first bending critical speed region and the maximum rotor vibration displacement in acceleration operation is less than half of backup bearing gap. The rotor vibration displacement and current responses of the rotor in different unbalances are measured in order to analyses the influence of the rotor unbalance on vibration characteristics of AMBs-flexible rotor system. It is shown that the proposed controller can make the rotor system smoothly pass through its first bending critical speed region. The rotor imbalance has a significantly influence on the control performance and stability of AMBs-flexible rotor system. The experiment results give a support on the high-performance control strategy of AMBs-flexible rotor system.

The disturbance induced by the rotation of dual axis flex solar wing is the important factor which impacts satellite attitude and pointing accuracy and stability of satellite precise payload. The flexible multibody system method based on recursive formulation is proposed to solve the dynamics problem induced by satellite dual axis flexible solar wing rotation. The satellite dynamics equations are established by considering orbit mechanics，satellite configuration，solar wing flexibility and solar array drive assembly and momentum wheels. As an example of a satellite with dual axis solar wing，the research on multibody dynamics simulation of satellite electromechanical coupling is developed，and the simulated attitude angle and angular velocity of satellite are compared with the corresponding telemetry data. The research shows that the simulated attitude angle and angular velocity of satellite agree well with the corresponding telemetry data，which proves the correctness of the model，The rotation of flexible dual axis solar wing will produce big disturbance torque and attitude angle，the control torque needs to be distributed to momentum wheel assembly for the accurate simulation results，and the disturbance torque of floating satellite caused by the rotation of solar wing was obtained by simulation，which can give the reference condition of ground test verification of solar wing rotation.

During real-time hybrid simulation（RTHS） of nonlinear specimens，the interaction between the specimen and the loading system can lead to variations in the specimen’s behavior，consequently affecting the time delay in the servo system. Online estimation of the system’s time delay enables the application of an adaptive time-delay compensation method for controlling time-varying systems. Nevertheless，during the initial stages of parameter identification，the estimated values frequently exhibit notable fluctuations，which can have a detrimental impact on the effectiveness of control. To this end，a two-stage adaptive time-delay compensation method driven by the inverse model for RTHS is proposed. Firstly，the inverse model controller of the system is used to perform coarse compensation to eliminate the test error caused by the main time delay. Then，the adaptive delay compensation method based on recursive least squares is used to compensate the remaining delay to further control the accuracy. By using the two-story shear frame as the prototype and the self-centering viscous dampers as the specimens，a time-delay compensation RTHS is carried out simultaneously on the two experimental substructures. Numerical simulations and experimental results show that the control accuracy of the proposed method is higher than that of the single-stage time-delay compensation method，and it can be applied to RTHS involving multiple experimental substructures.

Based on a large depot project in Chongqing，the vibration and secondary noise characteristics and human comfort of the over-track buildings induced by metro operation in the depot are studied. The vibration characteristics of the depot are analyzed by field measurement. Combined with the numerical simulation method，the finite element model of the track-soil-depot-over-track buildings is established based on the metro-track coupling theory and the finite element theory. The vibration and secondary noise characteristics of the top buildings under train excitation are analyzed and evaluated. The combined annoyance model of vibration and secondary noise is constructed by combining psychology and fuzzy mathematics to analyze the human comfort，and the annoyance is used as the evaluation index. The results show that under the train operation，the vibration level of the throat area is the highest，and the vibration stability for different areas of the depot is as follows：the inner area > the throat area > the upper cover area. As the lateral propagation distance increases，the maximum Z vibration level of the platform decreases approximately linearly. The vibration peak of each building on the top is 12.5~20 Hz，and the main frequency band of secondary noise is 63~80 Hz. The vibration and secondary noise of each building attenuate with the increase of floors，but the vibration and secondary noise of residential building are amplified after 12 floors. The vibration of each building on the upper cover do not exceed the standard，but the secondary noise exceeds the standard in the commercial building，and the maximum exceeding value is 4.9 dB（A）. The annoyance results obtained by the joint annoyance model are in good agreement with the standard evaluation results，but the annoyance can refine the influence of vibration and secondary noise on human comfort. The model calculation shows that although the first floor of the residential building meets the standard limit，the joint annoyance is above 0.6 at night，and the evaluation using the joint annoyance rate model is more demanding.

Compared with the in-plane seismic performance，the out-of-plane seismic performance of reinforced concrete shear walls is weak and usually neglected，which leads to an inadequate study of the out-of-plane damage mechanism of shear walls and a lack of clear protective measures，and the overall seismic performance of shear wall structure is also unsafe，which needs urgent attention. In order to compare the similarities and differences in seismic performance of reinforced concrete shear walls when subjected to in-plane and out-plane loads in different directions and to clarify the key influencing factors，low cyclic loading tests are conducted on typical shear wall specimens in-plane and out-plane directions，and the macroscopic test phenomena，hysteresis curves，skeleton curves，stiffness degradation curves，energy dissipation capacity and ductility in both directions are compared and analyzed. The moment-curvature simulations of shear wall sections in both in-plane and out-plane directions are analyzed，and the results obtained from multiple sets of constitutive models are compared with the experimental results. Combined with the finite element variable parameter analysis，the effects of parameters such as axial pressure ratio，wall thickness，height-to-width ratio and concrete grade on the seismic performance of in-plane and out-plane are analyzed. Based on the endurance time analysis，the time-history response of structural displacement with seismic magnitude is studied. The results show that the seismic performance of shear walls outside the face is significantly weaker than that inside the face，and the bearing capacity is only 1/20~1/15 times of the latter，among which the wall thickness and height-width ratio are the main parameters affecting the seismic performance inside and outside the face. The out-of-plane nonlinear analysis of the cross-section can be performed more accurately and quickly by using the principal structure model proposed in this paper and some traditional principal structures. In the seismic design of shear walls，especially for the single directional wall with less structure，both in-plane and out-of-plane seismic performance should be ensured，and the thickness and aspect ratio of shear walls should be reasonably controlled. Wall damage assessment by using elastic-plastic energy dissipation difference rate has the characteristics of obvious differentiation and reasonable threshold value.

In response to the challenging issue of low-frequency continuous spectrum reduction and isolation of ship equipment vibration，a vibration reduction method based on surface wave energy attenuation is proposed. Taking the rubber-fiberglass composite vibration system as an example，the damping characteristics of rubber surface waves are calculated using the finite element method. The influence of parameters such as thickness，damping coefficient，and Young’s modulus on surface wave attenuation is preliminarily explored. Experimental tests on rubber surface wave attenuation are conducted to validate the effectiveness of the surface wave attenuation method. The results demonstrate that the surface wave effect has a good vibration reduction performance，especially at high frequencies. The surface wave attenuation effect strengthens with increasing medium thickness，but not in a completely positive correlation. Reduction of the medium’s elastic modulus enhances the attenuation effect noticeably. Increasing damping is beneficial for surface wave attenuation. Compared to full-coverage rubber layers，local coverage of rubber layers on top of the isolating foundation provides better vibration reduction benefits.

In practice，earthquakes typically involve a mainshock followed by a series of aftershocks，and their occurrence is highly unpredictable. The mainshock damages the structure，and the aftershocks worsen the response and damage of the structure. However，no studies have investigated the effects of stochastic seismic sequences on AP1000 nuclear power plants. This paper proposes an analytical framework for studying the dynamic response and reliability of AP1000 nuclear power plants under stochastic main aftershocks. Stochastic main aftershock sequences are generated using the physical stochastic function model of ground motions，narrow-band harmonic group superposition method，and Copula function. The dynamic response of the AP1000 nuclear power plant is analyzed by using ABAQUS software. The direct probability integration method （DPIM） is used to obtain the probability density function of the maximum displacement response in the horizontal direction of the shielded building，and its dynamic reliability is calculated. The results show that the acceleration and relative displacement of the top of the shielded building and the steel containment vessel have increased to varying degrees after the aftershock，compared with experiencing the mainshock only. Additionally，the damage area between the water tanks and the vents has expanded. The aftershocks could cause further damage to the nuclear power plant. The dynamic response of nuclear power plants exhibits a high degree of randomness due to the stochastic ground motions. Aftershocks can reduce the reliability of nuclear power plants to varying degrees under different thresholds.

Focusing on a type of cable-bracing inerter system that utilizes positive and negative teeth ball screws to achieve self-balancing properties，this paper explores the prospect of its application in high-rise or super high-rise structures with complex deformation characteristics of bending and shearing. This paper develops a simplified model for the dynamic analysis of bending-shear structures based on the modified Timoshenko beam theory in order to take into account the accuracy and computational efficiency of the simulation of the original structural dynamic characteristics. Three types of cable layout schemes are proposed for the cable-bracing-self-balancing inerter system，and the appropriate cable layouts for the structures with different bending-shear deformation ratios are verified. A quantitative metric is proposed to optimize the anchorage position for structure-specific modal control. The accuracy of the optimization results is confirmed in the time and frequency domains through the application of fixed-point theory for single-modal control. The following conclusions can be derived. The higher the percentage of bending deformation of the structure is，the more effective the vertical connection of the cables will be，and the more effective the diagonal connection will be as the percentage of shear deformation increases. With regard to structure-specific modal control，the optimized anchorage position and fixed-point theory methods can significantly increase the damping efficiency of the inerter system.

Post-tensioned prestress，self-centering brace and shape memory alloy （SMA） are the main ways to realize the self-centering of the structures. However，the construction of post-tensioned prestress is complex，the concentrated force generated by self-centering brace may cause joint damage，and the SMA is expensive. The disc springs are preloaded to provide the self-centering force. A self-centering rebar splice is developed to connect the longitudinal rebars in the reinforced concrete structures. The calculation method of the stiffness，preload and effective stroke of the self-centering rebar splice is established. Four rebar splices with different preload force，stiffness and effective stroke are designed and manufactured，and the mechanical properties of the rebar splices are tested. The parameters of the rebar splice adopting the Bouc-Wen model are identified based on particle swarm optimization algorithm. The results show that the self-centering rebar splice has a stable half-flag hysteretic curve and excellent self-centering performance. The Bouc-Wen model can accurately describe the hysteretic characteristics of the rebar splice，and the fitting data are in good agreement with the test data.