Piezoelectric materials are often used in the fields of vibration energy harvesting and structural vibration suppression due to the excellent electromechanical coupling characteristics. This paper introduces a new shunt with switchable and manipulable force (mechanical) and electrical energy, using the primary and secondary energy conversion function of the flyback transformer based on the existing switching piezoelectric shunt. Based on the positive and negative piezoelectric effects, this paper designs the branch circuits for absorbing energy to suppress vibration and injecting energy to control vibration respectively, resulting in a highly efficient and stable structural vibration control system. The paper introduces the operating principles of the proposed new piezoelectric shunt branch and derives the decay rate models of structural amplitude under different energy manipulation conditions. The relationship between the effect of different energy manipulation methods and the amplitude of the structure is discussed through experiments. Results show that the introduced energy-manipulated shunt branch can realize highly efficient structural vibration suppression depending on the damping requirements of actual scenarios.

Capable of capturing offshore wind energy, the floating wind turbine is one of the primary research interests for researchers in the wind energy community. Researchers usually adopt two-dimensional low-degree-of-freedom simplified planar models for offshore barge-type wind turbines, where the model parameters are identified by the nonlinear least square method. In this case, the accuracy of these models depends highly on parameter fitting. Given the unique structure of offshore floating wind turbines and the surrounding environment, a multi-degree-of-freedom coupled dynamical model is necessary to yield more realistic dynamic behaviors. In this paper, we present a coupled dynamic model with 16 degrees of freedom for the multi-body system of barge-type offshore floating wind turbines under the combined action of wind and waves. The model accuracy is verified through numerical simulation using OpenFAST, developed by the National Renewable Energy Laboratory (NREL). In particular, the modified Blade Element Momentum theory is used to calculate the blade aerodynamic load, the linear potential flow theory is used to determine the wave load, and the quasi-static method is used to obtain the tension of the mooring systems. Besides the generator torque control and blade pitch control, a bi-directional tuned mass damper (TMD) is placed in the nacelle to mitigate the structural vibration of the floating wind turbine of the barge-type, where a limiting device is introduced to limit the TMD stroke. Subsequently, the control parameters are optimized by the method of exhaustion and the genetic algorithm. The simulation analyses show that the model proposed in this paper accurately alculates yields the dynamic response of the barge-type offshore floating wind turbine. The bi-directional TMD with collision mechanism is efficient in mitigating the structural response.

This paper presents a dynamic analytical model of periodic corrugated sandwich structures by using the dynamic stiffness(DS) method. In the model, the coupled structure is decoupled into several open cylindrical shells and rectangular plates, and then based on Kirchoff’s thin plate theory and Flügge’s thin shell theory, the DS matrices of substructures under the condition of simply supported on the opposite side are derived. According to the continuity condition and equilibrium conditions on the coupling boundary, the coordinate transformation matrix of each substructure is derived, and the global DS matrices of the periodic structure are assembled using a similar strategy to the finite element method (FEM). Based on the assembled global DS matrices, the vibration characteristics for the three types of periodically corrugated sandwich structures are calculated, and the results are compared with those from FEM solutions. The results show that the presented model can obtain accurate calculation results with fewer degrees of freedom. In addition, the effects of different core styles and geometric parameters on the band gap characteristics of the periodic sandwich structure are also explored.

In the field of low-frequency vibration isolation, aiming at the issues of insufficient bearing capacity of linear system and stiffness hardening and instability caused by nonlinear jump of traditional quasi-zero stiffness vibration isolation system, a mechanical model of the bionic limb-like quasi-zero stiffness isolation system was established by using the bionic limb-like structure as the negative stiffness element and the positive stiffness spring in parallel. The static characteristics of the system were analyzed; A dynamic model was established based on the Lagrangian equations, and the harmonic balance method was used to analyze the dynamics equations of the system analytically; Through theoretical analysis and experimental research, the isolation characteristics of linear and traditional quasi-zero stiffness isolation system and bionic limb quasi-zero stiffness isolation system were compared and analyzed, as well as the influence of excitation amplitude on the isolation performance and stability characteristics of the system. The results show that compared with the linear system and the traditional quasi-zero stiffness isolation system, the bionic limb-like quasi-zero stiffness isolation system not only ensures the system has a higher bearing capacity, but also effectively reduces the displacement transmissibility and expands the vibration isolation through the design of structural parameters. The frequency bandwidth improves the stability and vibration isolation performance of the system in complex excitation environments.

Based on the approach that ‘replace curved by straight’, the steady combined force is introduced directly into the fluid structure interaction vibration differential equation of straight pipe to describe straight-curved one’s transverse motion. Taking clamped-elastically supported combined pipe as an example, the new transfer matrix based on Laplace transform is used to derive the system’s characteristic equation calculating its natural frequency, and then the vibration characteristics such as natural frequency and critical velocity are studied. During this process, influences of the steady-state combined tension, flow model modification factor, and system’s components etc. on the vibration characteristics are investigated. According to the above investigation, the ‘fake coupled-mode divergence’ is firstly put forward, it can be concluded that different steady-state combined combined tension may lead to different critical velocity, change of system’s components may lead to distinguishing judgement for stability. The vibration differential equation is also established based on the approach ‘replacing straight by curved’, results of the above two thoughts are verified to be the same. The above investigation can provide insights for studying vibration characteristics of other types of pipes and behaviors of other fluid structure interaction mechanics as well, and be of high guiding meanings for theory and values for practice.

A two-stage high-static-low-dynamic stiffness vibration isolation system composed of Euler buckling beam negative stiffness regulator and two-stage linear vibration isolation system in parallel is tested and studied. The mechanical principle of high-static-low-dynamic stiffness is described, and the compression test of the Euler buckling beam negative stiffness regulator prototype is carried out to verify its negative stiffness mechanism. According to the different parallel forms of the negative stiffness regulators, two vibration isolation systems, constrained and unconstrained, are proposed. The dynamic equations of the negative vibration isolation model of the system are solved, and vibration isolation performance of the two types of vibration isolation systems with the different upper and lower stiffness are analyzed in combination. Two vibration isolation test systems of high-static-low-dynamic stiffness vibration isolation systems are built, and their vibration isolation performance is verified by sweep frequency and fixed frequency tests, and the reasons for the deviation of the results are analyzed.

In modern daily life, people are often exposed to many types of vibrations generated by machine operations, traffic and other human activities. These vibrations can cause annoyance to residents, and even interfere the operations of precision instruments. Generally, these adverse effects of vibrations can be eliminated or prevented by installation of various types of wave barriers, such as multi-row of holes. In the paper, the investigation is focused on effects of using multi-row of holes for the reduction of nearby vibration response generated by dynamic machine foundation laid on saturated soil. Two semi-analytical BEM models are established to calculate the environmental vibrations due to the machine foundation and the vibration isolation efficiency by multi-row of holes, respectively. In order to increase calculating efficiency of the semi-analytical BEM, a simple SPMD parallel algorithm is developed using Matlab software. The SPMD parallel algorithm is optimized by using the corresponding relationship between holes on the spatial coordinates. By using the optimized SPMD parallel algorithm, the effects of the model parameters on effectiveness of vibration isolation are calculated and discussed in detail. The results show that the optimized SPMD parallel algorithm of semi-analytical BEM is much faster than the chained program dramatically. Multi-row of holes can isolate the ground vibrations successfully, and the holes layout has less effect on the screening efficiency. Increasing the radius and the number of holes in a row, decreasing the net spacing between two successive holes can all lead to an increase in the screening effectiveness, while the rows of holes and the net spacing between two successive rows have less effect on the screening effectiveness. Further, the distance between the rigid foundation and wave barriers can has a limited impact on vibration mitigation effectiveness. According to the results, it’s suggested in the design that two-row of holes is recommended and the hole depth, radius and the nest spacing between two successive holes should take the values of 1.0, 0.15 and 0.1, respectively.

Seismic research technologies of power systems focus on the design, analysis and disaster mitigation before earthquakes.To quickly assist the emergency work after earthquakes, this paper proposed a post-earthquake evaluation method facing porcelain cylindrical equipment that uses monitoring data to predict structural stress responses. This method establishes a stress response proxy model by integrating machine learning and swarm intelligence evolution technologies, then builds refined simulation model, and conducts response analyses to form structural response database. Based on this, the proxy model can be trained and evaluated.Once the structural responses can be monitored, the proxy model can supply the stress response rapidly after earthquakes to help the post-disaster detection. A case study was performed using 1100 kV transformer bushing, and the evaluation models were vali-dated by shaking table tests and theoretical model based on distributed parameter system. The results indicate that using acceleration monitoring data can accurately evaluate the base stress of porcelain cylindrical equipment. Particle swarm optimization can efficiently adjust the internal structures of evaluation models, further increasing the model accuracy. The accuracies of evaluation models were validated by both shaking table tests and theoretical model.

In this study, a novel semi-supervised fault diagnosis of planetary gearboxes based on manifold regularized support higher-order tensor machines (MRSHTM) is proposed. In the MRSHTM, CANDECOMP/PARAFAC (CP) decomposition is introduced to exploit the intrinsic structural information of tensor data, and tensor-based inverse multiquadric kernel function (Tensor-IMKF) is defined to construct a Laplacian operator. The constructed graph matrix can better describe the manifold structure between tensor data. Besides, the one-versus-rest (OVR) strategy is introduced into the MRSHTM model for multi-class fault diagnosis of planetary gearboxes. Hierarchical multiscale permutation entropy (HMPE) is adopted to extract the three-order tensor features “channel×hierarchical layer×scale”, and then the extracted HMPE values are fed into OVR-MRSHTM for automatic fault identification. The results suggest that the proposed method can achieve semi-supervised fault diagnosis of planetary gearboxes in tensor space.

Deep learning methods have shown great potential in the field of fault diagnosis of train wheelset bearings, but their effective implementation is based on the correct matching between various types of data and category labels. For data with a small number of label error samples, traditional deep learning methods are difficult to achieve the expected diagnostic effect. To address this issue, this paper proposes a fault diagnosis method combining box graph method and feature fusion model is proposed to address this issue. In this method, the outlier in each group of bearing signals is removed by box graph method, and the remaining data is expanded by the SMOTE method to restore to the original data size; Input the processed sample data into the improved feature fusion model for fault identification and classification. The experimental data of train wheel bearings was used for validation. The results showed that compared to directly using traditional neural network models for fault diagnosis, the diagnostic accuracy of the method proposed in this paper is higher, indicating that the method has better processing performance for bearing data with a small number of label error samples.

Aiming at the problems that the existing convolutional neural network cannot fully extract the correlation features between rolling bearing time domain signals, the large number of samples required for model training and the insufficient generalization, A new method for diagnosing multi-condition faults of rolling bearings based on an enhanced convolutional neural network model is proposed. The length of the bearing single-revolution fault characteristic signal is calculated according to the rolling bearing speed and sampling frequency, then the complete information of the single-revolution time domain signal is encoded by Gramian Angular Difference Field coding technology to generate the corresponding feature image, enabling the neural network can visually learn the time domain signal correlation features. The 7×7 deep convolutional layer of the ConvNeXt model is reconstructed by using the asymmetric convolution in the ACNet network model: that is, two 3×3, one 1×3 and one 3×1 asymmetric small convolution kernel are used to reconstruct the 7×7 convolutional layer in the form of a multi-branch structure combination, which enhances the feature extraction efficiency of the ConvNeXt model. The data augmentation module and learning rate decay strategy of the ConvNeXt model are improved to raise the generalization of the ConvNeX model under small-sample training, to build an enhanced deep convolutional neural network model IConvNeXt. Different fault diameters of Case Western Reserve University, composite rolling bearing faults of Southeast University and variable speed bearing fault data sets of Ottawa, Canada are used for experimental verification, the results show that the proposed IConvNeXt model achieves a fault diagnosis rate of 100% for different fault diameters and composite faults of rolling bearings, and a fault diagnosis rate of 99.63% for variable speed bearings. The proposed method is experimentally compared with RP+ResNet, RP+ IConvNeXt, time-frequency graph+DCNN, MLCNN-LSTM, MTF+ IConvNeXt and other methods, the results were condicted to validate that the fault diagnosis effect of the proposed model is better than that of other methods under less sample training and has strong generalization performance.

Aiming at the complex mechanism and operation characteristics of the mechanical system of diesel engine on RO-RO passenger ship, a multi-component nonlinear vibration signal decomposition method and vibration characteristic parameter extraction strategy are proposed. The signal is decomposed into intrinsic mode function (IMF) components via empirical mode decomposition and restrained the end effects in empirical mode decomposition (EMD) by symmetrical extension. The sensitive component is extracted by the correlation. The characteristic frequencies are matched according to the amplitude demodulation spectrum via 4 order high energy operator (4th-HEO). The proposed method is illustrated by the three-dimensional vibration signals under 0 load and 100 load operation conditions of the RO-RO passenger ship. The results show that the analysis performance of vertical signals are better than other axial signals. And for the 9-cylinder 4-stroke diesel engine, the amplitudes of 0.5 times and 4.5 times are very prominent, and are more sensitive to load changes.

Aiming at the problem that the existing damage identification methods are difficult to track the structural damage in real time and require a large amount of calculation, a model order reduction and online damage identification method based on the combination of recursive proper orthogonal decomposition (RPOD) and strong tracking extended Kalman filter (STEKF) is proposed.The structural damage identification under dynamic load is studied. The RPOD method is used to update online and construct the reduced-order model reflecting the structure state in real time, which solves the problem of large calculation and difficult convergence of dynamic analysis of multi-degree of freedom structures under unknown loads. Meanwhile, the evolution of damage is tracked and located. The STEKF method is used to track the state vector of the reduced-order model and identify the reduced-order model parameters degraded by damage. The feasibility of the proposed method is verified by numerical simulation of a six-story shear frame and model test of a three-story steel frame. The results show that the proposed method can accurately construct the reduced-order model and track the time-varying history of the reduced-order model parameters. Meanwhile, it can effectively identify the location and extent of the damage of the shear building structure, even when dealing with high levels of noise, it retains high accuracy.

In order to reveal the damage distribution law of self-centering braced structure under simultaneous and successive actions of earthquake and wind, the damage of beams and columns and global damage of a 50-story steel frame self-centering braced tube structure are analyzed under earthquakes with different intensities and wind with a return period of fifty years. The results indicate that under earthquake alone and under simultaneous action of earthquake and wind, beams in braced tube are damaged earlier than those in exterior frame, and the damage of columns in braced tube develops faster than those in exterior frame. The simultaneous action of earthquake and wind increases the damage degree of columns and increases the maximum damage value of columns at the 31st story by 78.6%. As earthquake intensity increases, the amplification influence of the action of wind on structural global damage increases gradually. Under successive action of earthquake with different intensities and wind with a return period of fifty years, the action of wind increases the average value of maximum residual deformation ratio of seismic damaged structure. When the peak ground acceleration is 10 m/s², the average value of maximum residual deformation ratio of seismic damaged structure is increased from 0.325% to 0.330% caused by wind load. However, wind load has less influence on the damage state of the most severely damaged member in seismic damaged structure.

The cable-net structural system of FAST is a flexible tension cable net, consisting of a main cable net, several hydraulic actuators and controllers, which is the world’s largest span, the highest precision, and the first active shape-changing cable-net system. Its characteristic is that the cable net form can be adjusted according to requirements, but it also results in the cable boundary conditions constantly changing with the cable net form, which brings huge challenges to cable force identification. In order to accurately identify cable forces of the active shape-changing cable-net system, a method for identifying cable forces of variable elastic boundary supports is proposed. An equivalent single-degree-of-freedom model of the cable is established, and the mathematical expressions of the cable frequencies between ideal hinge and elastic boundary support are derived. The first-order frequency is then corrected based on the first-order mode values at the mid-point and both ends of the cable. The cable force identification method of the active shape-changing cable-net system which is based on the string vibration theory is proposed. Numerical simulations are carried out to verify the accuracy of the proposed method, and parametric analyses are also conducted. The method is proved to be practicable and applicable through numerical simulations and field measurements to identify the cable force of the FAST cable net.The results show that the relative errors of cable force identification are within 1% in the numerical simulation and less than 5% in the field measurement. The method takes into account the complex boundary conditions of cables, avoids solving for unknown boundary constraint stiffnesses, and extends the engineering applicability of the traditional string vibration theory.

The deflection influence line and strain influence line can integrally reflect the flexural stiffness of beam bridge section. In the process of obtaining the measured time-history response of beam bridge, the response of beam bridge involves the influence line information and structural dynamic components, and is interfered by the multi-axis effect of loading vehicle under vehicle moving load. In order to identify the influence line of beam bridge structure accurately, the empirical mode decomposition was proposed to eliminate the dynamic component in the measured data of beam bridge, and the quasi-static response data of beam bridge containing the multi-axis effect was obtained. Combined with the sampling frequency and vehicle wheelbase, a mathematical model was established to identify the influence line, and the multi-axis effect of vehicle was converted into unit concentrated load. Tikhonov regularization method was used to accurately solve the stable solution of the influence line of the beam bridge. Through the establishment of numerical simulation models of 1/2 two-axle vehicle-crossing simply-supported beam bridge and three-span continuous beam bridge with variable section, the deflection and strain time-history responses of simply-supported beam bridge and three-span continuous beam bridge at different vehicle speeds were extracted, and the feasibility and effectiveness of identifying influence lines of beam bridge based on empirical mode decomposition and Tikhonov regularization method were verified. The deflection influence lines and strain influence lines of the structural examples of the beam bridge were identified accurately, and the identification effect of the influence lines was evaluated quantitatively by establishing error index. The research also found that the identification effect of the influence lines of the beam bridge decreased with the increase of the loading vehicle speed.

In the seismic design of bridge structures, the influence of local site conditions at piers on the seismic response should be considered. The multi-support response spectrum method is a common method for seismic performance analysis of bridge structures under spatial ground motion. For deep-water bridge, the existing method cannot include the water-structure interaction.Based on the radiation wave theory, this paper proposed a multi-support response spectrum considering the water-structure interaction by introducing the term of hydrodynamic pressure into the vibration equation of the bridge. The correctness of the method was verified. Taking a typical five-span continuous girder bridge as an example, the seismic response of the bridge under different site conditions is studied by changing the site type of the pier, seismic intensity, and design seismic group. The influence law of local site effect on the seismic response of the multi-span continuous girder bridge is revealed. The results show that with the softening of site of pier 3, the relative displacement at top of pier 3 decreases by up to 93.0% at most. The influence of site type on pier displacement is greater than that of the axial force of girder and the bending moment at bottom of pier. With the increase of seismic intensity, the relative displacement at top of pier, axial force of girder and bending moment at bottom of pier increase by 7 times. With the increase of epicenter distance, the relative displacement at top of pier increases by 41.0%, the axial force of girder increases approximately by 18.0%, and the bending moment at bottom of pier increases approximately by 30.0%.

In order to investigate the dynamic response law of concrete-filled steel tubular composite single pile with large diameter and variable section under different types of seismic waves, 5010 wave, 1004 wave, Kobe wave and El-Centro wave with ground motion intensity of 0.15g were selected through indoor shaking table test relying on Xiangan Bridge project of Xiamen Second East Passage. The pile acceleration, horizontal displacement, bending moment and pile foundation damage of large diameter variable section concrete filled steel tube composite pile are studied. The test results show that the dynamic response characteristics of large diameter variable section concrete filled steel tube composite pile are different due to the different spectral characteristics of different seismic waves. Pile top acceleration maximum, pile top horizontal displacement maximum and pile bending moment maximum are the maximum under 1004 wave, and the minimum under Kobe wave. The maximum bending moment of pile body did not exceed the designed flexural bearing capacity of pile foundation. In the design of flexural bearing capacity of pile foundation under the action of earthquake force, the design of flexural bearing capacity at the interface of soft and hard soil layer is emphasized.

To investigate the influences of charge structures on the blast-induced ground vibration characteristics in hydraulic blasting, several onsite experiments were conducted in the context of Xinbin tunnel at the Shenyang to Jilin Expressway. Based on the onsite experiments, the peak particle velocity (PPV) and dominant frequency (DF) were analyzed under different kinds of charge structures, which includes the normal charge structure, the water bags located in the top of blasthole, the water bags located in the blasthole collar and the water bags located in the both ends of blasthole. In addition, the distribution laws of ground vibration under different charge structures were further studied using numerical simulation. The research results indicated that, compared with the normal charge structures, less explosive energy is converted into vibration energy in hydraulic blasting, resulting in smaller PPVs and higher DFs. Within 5 m of the cross section along the tunnel excavation face, the PPVs of blasting vibration under the normal charge structure exceed the vibration safety criteria, which is adverse for the safety control of ground structures. The converted vibration energy is relatively smaller along the direction of water bags in blasthole, but on the opposite direction of the blastholes more explosive energy is converted into vibration energy. In tunnel blasting excavation, the charge structure of the water bags located in the both ends of blasthole was recommended to promote the uniform distribution of vibration energy and minimize the disturbance to the surrounding structures.

In the realm of engineering structures, the distribution of structural parameters often remains uncertain due to a lack of sufficient data, presenting a common and intricate challenge in structural reliability analysis. This paper presents a novel linear moment method for assessing the seismic reliability of random structures with unknown distributions. A random dynamic system is constructed using only two basic random variables: (1) the first four-order linear moments derived from the structural random parameters, expressed as a univariate cubic polynomial with a random function involving standard normal random variables; (2) A random function-spectral representation model is utilized to describe the non-stationary seismic ground motion. On this basis, representative point sets for the two basic random variables are determined using number-theoretical methods. Through time-domain analysis, extreme structural responses are computed to evaluate the samples of the performance function and its linear moments within the specified limit state. The seismic reliability index derived from linear moments is established by solving the univariate cubic equation roots. To demonstrate the proposed method’s applicability, a nonlinear single-degree-of-freedom system with unknown parameter distributions is analyzed, and its effectiveness is verified by comparing the results with those obtained using Monte Carlo simulation.

Railway bridges must have sufficient stiffness to ensure high-speed train safety, increasing seismic response. The Sichuan-Tibet Railway network has extended westward. This research analyzes the fourth level of high-speed railway bridges.Three 1/5 and six 1/8 scaled-down high-speed rail(HSR) round-ended rectangular-shaped cross-section solid(RERSCSS) concrete pier were tested and evaluated. The piers survived the earthquake with a peak acceleration 0.96g (prototype 0.32g, seven degrees high-level earthquake). Bridge pier specimens showed no concrete cracking or spalling. The code-designed bridge is seismically safe. When the seismic energy reached 1.71g (prototype 0.57g, eight degrees high-level earthquake), the bridge piers showed moderate to severe damage in the cis-bridge direction. At giant earthquake 1.86g, no bridge abutments collapsed. The study shows that increasing longitudinal reinforcement rate increases structural energy dissipation under the same ground shaking, but increasing seismic protection level increases it more, indicating that test piers can take larger earthquake loads. The bridge pier’s energy dissipation and hysteresis curve depend on the longitudinal reinforcement rate. High-speed rail piers are not designed for ductility. Therefore, their volume hoop rate and hysteresis performance are low. Based on the analysis, the seismic design classification may be upgraded from the third to forth levels.

There are several shortcomings in the assessment of human-induced vibration in walkways, including a focus on structural response rather than pedestrian comfort, the reliance on structural vibration response to evaluate pedestrian comfort, and the limitations of data collection methods. To address these problems, this paper proposes a more comprehensive approach, namely human-induced vibration serviceability assessment of full-path footbridge based on computer vision with source-path-receiver. The proposed method captures video sequences of both the footbridge and pedestrian movements under pedestrian excitation using computer vision techniques, and then utilizes the segmental optical flow method and the MMTracking algorithm to obtain the vibration response of both. The acceleration responses of the pedestrians obtained from the above extractions and transformations are used as an evaluation index for the vibration comfort of the pedestrian bridge in terms of the root mean square value of acceleration. To validate the feasibility and accuracy of this method, experiments were conducted on the pedestrian bridge in the laboratory. The results show that the computer vision technology can accurately and contactlessly capture the pedestrian dynamic information of the footbridge, which is more reasonable than the conventional method which only evaluates the vibration comfort of the footbridge based on the structural vibration response. By addressing the shortcomings of current assessment standards and methods, this approach provides a more comprehensive and accurate means of evaluating the vibration serviceability of footbridges, considering both the structural response and the actual experience of pedestrians.

The aerodynamic interference between tandem square cylinders is strongly influenced by their geometric shape. The change of corner shape of square cylinders will lead to the change of flow field, which will affect the aerodynamic performance of square cylinders. The influence and mechanism of wind load interference effect of tandem square cylinders need to be further studied.In this paper, the large eddy simulation method is used to investigate the impact and mechanism of corner cutting measures on the wind load of tandem square cylinders with subcritical spacing ratio and supercritical spacing ratio under two typical spacing ratios. The upstream and downstream cylinders are considered with or without corner cutting(the corner cutting rate is 10%). The wind pressure coefficient of standard tandem square cylinders is compared with the wind tunnel test results in literature to verify the effectiveness of the simulation method and parameter setting. effects of different corner cutting measures on the aerodynamic performance of tandem square cylinders under two typical spacing ratios are compared and analyzed from the perspectives of aerodynamic coefficient statistics and auto-spectrum, average and fluctuating wind pressure coefficient distribution. The mechanism analysis is carried out from the perspective of time-average and transient flow field.The results show that under the two typical spacing ratios, the corner cutting measures at different positions will affect the flow separation around the square cylinder, resulting in the change of flow pattern. The average and fluctuating wind loads of the square cylinder can be reduced more effectively by the corner cutting measures at both upstream and downstream square cylinders.Under the subcritical spacing, the shielding effect is significant, and the corner cutting measures change the separation and reattachment position of the separation vortex, and reduce the lift and drag of the downstream square cylinder significantly.