As a flexible bridge, the deflection control of the main girder is particularly important during the operation of a suspension bridge. To predict the vertical deflection of the main girder of an existing suspension bridge under the combined effects of random traffic flow and environmental temperature, this paper establishes an integrated deflection interval prediction method based on Convolutional Neural Networks (CNN), Long Short-Term Memory (LSTM) networks, probability density estimation layer, and bridge monitoring data. Using health monitoring data from the Nanxi Yangtze River Bridge, a time series training set of environmental temperature, vehicle load, and deflection monitoring data was established. The combined CNN-LSTM layers captured local features and long-term memory in the time series. A Gaussian distribution was used as the probability density function, and the parameters of the Gaussian distribution were evaluated using the maximum likelihood method, resulting in optimal deflection prediction values and probability intervals. Based on this, a method for identifying abnormal deflection and warning thresholds for the main girder of existing suspension bridges was proposed. The study shows that compared to LSTM and CNN-LSTM models, the CNN-LSTM-GD model has better predictive capabilities for small deflection fluctuations and extreme deflections, with deflection prediction values closely matching the monitoring data. Over a 24-hour time scale, compared to the traditional LSTM model, the CNN-LSTM-GD model improved the Root Mean Square Error (RMSE) and the coefficient of determination (R2) by 54.40% and 10.22%, respectively. Compared to the CNN-LSTM model, the improvements in RMSE and R2 were 38.43% and 5.31%, respectively.

Because of the large scale of the project, high efficiency, and to a certain extent can save the production cost of mining and stripping, cast blasting has been favored by the open pit mining industry in the United States, Australia and other developed countries. By combing and analyzing the development history of cast blasting technology in open-pit mines at home and abroad, the production characteristics of cast blasting technology are defined. The factors influencing the blasting quality in open-pit coal mine are analyzed from the aspects of strong controllable, weak controllable and uncontrollable, and the applicability conditions of the cast blasting technology in open-pit mining are also analyzed. Based on the theory of plane charge method and blasting seismic effect, the rock blasting mechanism of blasting technology is deeply analyzed, the four stages of rock throwing after explosive initiation and the evolution characteristics of rock strata are defined, and the seismic response characteristics of blasting technology are analyzed and summarized. Taking Heidaigou open-pit mine as an example, the application status of cast blasting technology is described in detail, the operation flow of cast blasting technology application is systematically analyzed, the internal structure and operation mechanism of cast blasting and dragline stripping technology is analyzed, and the bottleneck problems existing in the application of cast blasting technology are analyzed and summarized. Aiming at the intelligent transformation and upgrading of projectile blasting technology, the whole system process of cast blasting engineering, such as transparent geological information, intelligent blasting design, fine blasting construction, informatization of safety management, and precision blasting effect, is analyzed and refined respectively, from the aspects of disciplinary support, technical support and problems to be solved. The knowledge system and intelligent system architecture of cast blasting technology are constructed, the research trend of cast blasting technology in the future is proposed, and the applicability of cast blasting technology in other open-pit coal mines in china is analyzed. The research results can provide reference and basis for the upgrading and transformation of blasting engineering technology in other industries.

To address the issues with complex and variable vibration signals in gearboxes, which led to low diagnostic accuracy of existing gearbox fault diagnosis methods and the risk of weak fault features being overwhelmed by noise, a new fault diagnosis method was proposed. Firstly, entropy weight fusion algorithm was used to fusion vibration sensor signals at different locations, and vector weighted mean value algorithm (INFO) was used to optimize parameters in the variational mode decomposition (VMD) algorithm. A composite evaluation index was designed as the evaluation standard for parameter optimization. The Singular Kurtosis Differential Spectrum (SKD) method was employed to reconstruct the sensitive components. What’s more, the time domain and frequency domain features were extracted from the reconstructed signals and fed into the CNN model for classification. Finally, Shapley Additive Explanations (Shap) value method was used to rank the importance of input features. The impact of different feature combinations on model classification and specific fault identification was analyzed. The proposed method was validated on the Planetary Gearbox Dataset from Southeast University. It was shown that using the proposed feature combination for fault diagnosis, the CNN model achieves an accuracy of 98.24%, which is higher than other combinations. This provides an effective set of feature indicators for planetary gearbox fault diagnosis.

The crashworthiness of an aircraft is not only affected by its own structural design, but also closely related to the crash speed, the landing attitude, and the runway environment.The full-scale structure of a typical civil aircraft was taken as the study object, and a full-scale aircraft crash dynamics model, was established, which was then validated by the experimental data from the literature.Numerical simulations of crashes under different impact speeds, pitch angles, roll angles, and runway environment factors were further conducted to explore the influences of different factors on the aircraft crash response.The results show that as the impact speed increases, the initial peak of the crash load on the lower part of the fuselage and the platform load gradually increase, and the area of deformation of the fuselage gradually increases.With the increase of the pitch angle, the waveform of the crash load changes significantly, the load peak decreases significantly, the peak acceleration of the floor gradually decreases, the acceleration of the mid-fuselage structure is more sensitive to the change of the pitch angle, and the impact speed of the local fuselage structure of the aircraft is significantly affected by the aircraft pitch angle.Under the condition that the overall vertical impact speed of the aircraft remains unchanged, the greater the pitch angle, the greater the impact speed of the front fuselage section, and the overall non-linear increase trend from the nose to the rear fuselage is presented.The roll angle has little effect on the aircraft’s crash load and the acceleration peak of the wing, but has a significant effect on the acceleration peak of the fuselage floor.The deformation on the side of the fuselage bottom at the near roll direction increases, and a new plastic hinge is produced.Compared with the rigid runway, when crashing on the clay runway, the vertical impact load peak of the aircraft decreases, and the heading impact load peak increases significantly.The aircraft crashes on the clay runway and produces a gully-like deformation.The shape of the gully and the deformation expansion process under different pitch angles are significantly different.The deformation of the fuselage and the peak acceleration of the floor are smaller when crashing on the clay runway, and the risk to the safety of the passengers is smaller than that on the rigid runway.

Clunk noise caused by torque ripple under transient operating conditions is one of the main vibration and noise problems of IWM (in-wheel motor) drive systems. Large torque ripple may cause torsional vibration in the drive transmission system, seriously affecting ride comfort and safety. Therefore, conducting research on Clunk noise of IWM drive systems is of great engineering significance for improving the NVH performance of the system. The driving system of the inner rotor permanent magnet synchronous IWM is taken as the research object, and the mechanism of Clunk noise generation during vehicle testing is analyzed. Through bench testing, it was found that the impact vibration between teeth caused by the cogging torque of the motor is the main cause of Clunk noise. A multi-body dynamics analysis model of the IWM drive system was established based on Masta software, and the effectiveness of the model was verified through experimental data conclusions. The influence of various parameters on Clunk noise was analyzed using the control variable method. Through the analysis of key parameter influencing factors, it was found that motor speed and cogging torque have a significant impact on Clunk noise. A control scheme was proposed to suppress Clunk noise by reducing torque ripple caused by cogging torque. By optimizing the rotor skewed pole and injecting harmonic current, the torque fluctuation can be reduced from 3.8Nm to 0.24Nm, achieving the effect of improving the sound quality of Clunk noise. After optimizing the NVH test of the sample, the Clunk noise level was significantly reduced, and the subjective evaluation was acceptable. Solved practical engineering problems and improved the NVH performance of the wheel hub motor-driven transmission system.

The stiffened plate structures are widely used in engineering applications, and the rational layout of the stiffeners can effectively enhance the stiffness and load-bearing capacity of these structures. In order to achieve optimal stiffener layout design for thin plate structures, a new dynamic topology optimization method tailored for multi-phase material stiffened structures is proposed. Firstly, the stiffeners and thin plate are respectively considered as strong and weak materials and characterized by different bending stiffness, with use of equivalent stiffness method; Next, the Hilber-Hughes-Taylor-α (HHT-α) method is employed to solve the dynamic finite element model, and dynamic sensitivity analysis is conducted using the adjoint variable method with the discretize-then-differentiate approach; Furthermore, the effectiveness of the dynamic topology optimization method for stiffened plate structures is validated through a comparison of stiffener distribution topology optimization examples of a corner simply supported square plate with traditional methods. Finally, the stiffener topology optimization design is carried out for several typical thin plate structures using both single-phase and bi-phase materials under various loading and boundary conditions. The results show that the proposed dynamic topology optimization method for stiffened plate structures demonstrates flexible and effective optimization capabilities under dynamic conditions. By introducing bi-phase materials, the issues related to continuity distribution in single-phase materials are successfully overcome through reasonable material distribution and refined structural design. The optimized stiffener structure is continuous with complete force transmission paths, and significantly outperforms traditional methods.

Fault diagnosis models optimized through deep transfer learning have proven effective in addressing civil aircraft fault diagnosis tasks under variable working conditions, ensuring component reliability in in complex operational environments. However, the scarcity of high-confidence fault samples, particularly under varying conditions, due to the stringent safety requirements in civil aviation hinders the model's inference capabilities and increases the risk of overfitting. To overcome these challenges, we propose a Condition Diffusion-based Fault Diagnosis (CDFD) algorithm. The algorithm integrates a denoising diffusion model to conditionally generate high-confidence fault samples, thereby alleviating overfitting caused by sample scarcity. Unlike traditional diffusion methods that focus solely on sample distribution inference, the CDFD algorithm couples fault sample generation with decision-making optimization,  ensuring the quality of generated samples and significantly enhancing the diagnostic model’s generalization. Experimental validation on both simulated and real-world fault data demonstrates the efficiency of the proposed algorithm in handling real civil aircraft fault diagnosis tasks.

In structural strength design of ships, water entry slamming load receives great attention. Here, using computational fluid dynamics-finite element method (CFD-FEM) bidirectional coupling numerical method, the fluid-structure interaction problem of an elastic wedge  under gravity entering water in different flow field environments was studied. Firstly, taking wedge slamming in still water as an example, simulation results were compared with experimental ones to verify the correctness of CFD-FEM. Then, slamming loads, structural responses and flow field changes of elastic wedges with different water entry velocities and bottom oblique angles were analyzed when entering water in different flow field environments of still water, flow and waves. The results showed that water entry slamming of wedge  in still water is consistent with experimental results of model, so the numerical simulation has the reliability and feasibility;under action of uniform flow, when a wedge  enters water, due to wall reflection of structure to incoming flow, the flow velocity near wedge  is different from that far away from incoming flow to generate a pressure difference,  bottom of wedge  shifts to direction of incoming flow;when entering water at different wave positions, model equilibrium position is in direction of wave velocity, as the relative slamming velocity between wave and wedge  increases, the generated slamming load is larger than that in still water, high stress zone is mainly concentrated at wedge  bottom and weld position;the study results can provide a guidance for ship structure design and water entry slamming study.

In construction process of power grid, it is inevitable to pass through heavy icing areas. Surveys of icing in high-altitude areas showed that icing thickness on transmission lines varies with altitude to cause non-uniform icing along transmission lines. Moreover, de-icing of transmission lines under changes of external forces or environment is usually uneven. Here, non-uniform icing coefficient was defined according to non-uniform icing characteristics of high-altitude and high-altitude difference transmission lines. A finite element software was used to build a transmission line de-icing jump analysis model, dynamic characteristics of non-uniform and uniform icing conductors under different uneven de-icing modes were calculated to explore effects of icing mode, de-icing mode, conductor span and altitude difference on ice jumping height, conductor tension, tower unbalanced tension and ice jumping position of continuous transmission lines, and the simulation model was verified with real tests. The results showed that de-icing dynamic response of conductor under non-uniform icing condition is slightly elevated compared to that under uniform icing condition, effects of different de-icing modes on conductor’s maximum jump height positions are significant, which are generally located at 049-069 times conductor span; however, one entire span conductor de-icing is still the de-icing mode with the maximum ice jumping height, and the maximum ice jump height position is mainly concentrated at midpoint of de-icing span conductor; maximum tension of conductor under all operating conditions does not exceed its initial static tension; impact coefficient of tension during entire span conductor de-icing is 070, tension in chain type conductor de-icing process exhibits a monotonic decay with impact coefficient of 1.03; longitudinal unbalanced tension in deicing process is much higher than that in static state with impact coefficient of 146-175. The study results can provide important reference for designing transmission lines and formulating de-icing schemes.

Based on the research background of twin rotor actuator, a single drive twin rotor actuator active control device is proposed in this paper, which is mainly composed of mass block, space transmission gear group, motor and controller. The centrifugal force generated when the rotor is driven by the gear is used as the active control force to reduce the structural vibration. Compared with the traditional active mass damper, this design not only does not need to consider the linear travel limit of the guide rail, but also solves the problem that the motor in the dual drive twin rotor actuator is difficult to synchronize through structural optimization, and realizes more efficient and stable vibration control. In order to study the vibration damping performance of the single drive twin rotor actuator, firstly, the mechanical model of the single drive twin rotor actuator system, the single degree of freedom structure and the state equation of the single driven twin rotor actuator are established based on the mechanical analysis of Lagrange equation. Secondly, a controller combining pole assignment method and Super-Twisting Sliding mode control algorithm is designed for vibration reduction of single drive twin rotor actuator system, and the control parameters contained in the controller are optimized based on the improved Dung beetle optimization algorithm. Compared with other control algorithms, the proposed method not only enables easier acquisition of controller parameters but also eliminates tedious trial-and-error tuning, thereby streamlining practical engineering im-plementation. Finally, the stability of the system is proved by the Lyapunov function, and the feasibility and effec-tiveness of the Super-Twisting sliding mode control algorithm based on the single drive twin rotor actuator system are verified by the simulation experiments.

Damage to transformer windings caused by external short circuits is usually not only related to a single short-circuit process, but also to gradual deformation of windings caused by successive short-circuit impacts to generate irreversible cumulative deformation and reduce their anti-short-circuit ability. Here, firstly, a 110.0 kV transformer was remade to conduct multiple short-circuit impulse tests. Cumulative effect of short-circuit impacts on mechanical state damage of windings was verified by measuring changes of reactance and axial pressure of windings. Then, effects of cumulative effect on vibration characteristics of windings were revealed through time domain and frequency domain analyses of vibration signals on surface of fuel tank and axial impact force of windings. Wigner-Ville distribution method was used to process vibration signals, construct time-frequency matrix for realizing feature extraction, and calculate the membership degree of winding mechanical state based on fuzzy C-means clustering algorithm, a method for quantifying the cumulative effect of winding deformation was proposed, and the criterion for severe winding deformation was determined. According to the experimental results, it can be seen that the variation law of vibration characteristic parameters is highly consistent with the change rate of reactance and axial pressure. The study results can be applied in mechanical state assessment and early fault warning of windings, and provide important engineering reference value for safe and stable operation of transformers.

Aeroengine data exhibits complex characteristics such as multivariate, nonlinear, and dynamic variations, with significant spatiotemporal correlations. The majority of research, when analyzing data, often limits itself to a single multi-sensor scale or temporal scale, and frequently neglects the long-term dependencies among the data, thereby constraining its application in the task of predicting the remaining useful life (RUL) of aircraft engines.. To address this, a spatio-temporal fusion Transformer network model is proposed. This model retains the advantages of the multi-head attention mechanism and positional encoding in the Transformer architecture to accurately capture long-term dependency features. Firstly, an efficient fully connected network is adopted to replace the original decoding module, matching the attributes of the nonlinear regression problem in aeroengine RUL prediction while simplifying the model structure. Secondly, a spatial attention mechanism module is introduced to deeply explore the spatial features among different variables. Finally, the improved AIC criterion is applied to identify critical hyperparameters of the Transformer, addressing the challenge of selecting its hyperparameters. Multiple sets of experiments conducted on the C-MAPSS and PHM08 Prognostics Data Challenge have confirmed the effectiveness of the proposed model and its superior performance in prediction accuracy.

Explosive stress wave propagating in the rock cavity will occur scattering and dynamic stress concentration, which will affect the blasting effect. In order to investigate the dynamic response of the rock cavity surface under the effect of blast load, based on the explosion dynamics theory, the theoretical solution of the dynamic stress field on the surface of the rock cavity is obtained, and the effects of the radius of the cavity, the spacing between the blast source and the cavity, and the frequency of the incident wave on the distribution of the dynamic stress around the rock cavity are investigated. The results show that the dynamic stress factor δθθ and δϕϕ are symmetric about the XOY plane at the boundary of the cavity in the explosion stress field, and their maximum values are biased toward the explosion source. The dynamic stress factor δθθ curve is “petal-like”, and δθθ reaches the maximum value of 2.62 at θ=±72.19°, while the dynamic stress factor δϕϕ curve is “gourd-like”, and its maximum value occurs at θ=180°. The dynamic stress factor peak 2, peak 5 and peak 3 increase with the increase of the radius of the cavity, and the peak 1 and peak 4 gradually decrease. With the increase of R0, the peak 2, peak 5 and peak 3 show a gradual decrease trend, and gradually tend to be stabilized after R0>12m. The dynamic stress factor peak 1 and peak 3 show a gradual decrease trend, and gradually tend to be stabilized after R0>12m. The dynamic stress factor peak 1 and peak 4 increase first and then decrease with the increase in incident wave frequency, while the peak values 2, 3 and 5 continue to increase. The research results can provide a theoretical basis for the optimal design of engineering blasting parameters.

The dominant flutter mode of long-span suspension bridges varies with the erection stage of the main girder.This study investigates the mode transition during construction and its impact on aeroelastic stability.A 2 300 m-span suspension bridge with a closed-box girder was analyzed through free and forced vibration wind tunnel tests on segmental models at different erection stages.Critical flutter wind speeds and flutter derivatives were obtained.A double-mode coupled analytical method was employed to evaluate flutter performance throughout the erection process.The results indicate that before 58% of the main girder is erected, flutter is governed by symmetric mode combinations.During the transition stage from 58% to 66% erection, the dominant flutter modes gradually shift from symmetric to antisymmetric combinations.After 66% erection, flutter is controlled by antisymmetric mode combinations.The transition is caused by a rapid decline in aerodynamic damping of the antisymmetric mode.At the transition, the phase difference of antisymmetric motion drops sharply, vertical motion lags behind torsion, torsional energy contribution decreases, mode coupling intensifies, and aerodynamic energy dissipation increases.

Killing and detonation warhead has been widely used in many kinds of air defense and anti-missile weapon systems. This kind of warhead mainly realizes efficient destruction of incoming missile target through explosion shock wave and fragments. To investigate the coupled destruction capability of the explosive shock wave and fragments damage on the target under different explosion scenarios, cylindrical shell is selected as the effect target, a computational method that can classify the different explosion action fields is proposed based on the velocity change equations of the explosive shock wave and fragments, the LBE (LOAD_BLAST_ENHANCED) method is introduced to realize the effective simulation of the coupled damage condition on the cylindrical target under the synergistic effect of the explosive shock wave and fragments. The results show that: the material strength of the target is the main factor affecting the damage effectiveness, increase the strength of the target is a key factor in enhancing the ability of their own protection. In the premise of the initial explosion parameters are the same, the damage efficiency of explosion-related action is the highest, about 1.06~5.26 times that of shock wave alone, and the damage efficiency of combined action is about 1.06~1.44 times that of shock wave alone. 

The micro-vibration induced by the rotating components on the satellite is one of the key aspects that affect the working precision of the optical payload.The vibration isolation mechanism installed between the satellite platform and the optical payload can effectively suppress the transmission of micro-vibration to the payload.Based on the stable spherical pair-prismatic pair-revolute pair(3-SPR)parallel mechanism, along with diaphragm springs, eddy current dampers and piezoelectric actuators, an active vibration isolation platform for optical payload were explored and analysed.The dynamic modeling and analysis of the 3-SPR parallel mechanism were conducted and the kinematic features of its corresponding degrees of freedom were discussed in detail.The closed-loop control algorithm based on the acceleration and angular displacement measurements was further introduced.The rigid-flexible coupling dynamic model of this mechanism was established to provide the transmission function and to evaluate the passive and active vibration isolation performances of this parallel platform.The ground experiment verifies that the platform possesses desirable vibration isolation abilities, which achieves over 42% disturbance isolation, and paves the way for the future on-orbit applications.

In the dynamic load test of bridges, environmental noise interference leads to the distortion of bridge vibration signals, which affects the accuracy of bridge structural condition assessment. To address this issue, this paper proposes a hybrid denoising method that combines hippopotamus optimization algorithm (HOA), variational mode decomposition (VMD) and singular spectrum analysis (SSA). The HOA is used to optimize the key parameters of the VMD, and then the VMD decomposes the original signal into multiple intrinsic modal functions (IMFs). By calculating the correlation coefficient between each IMF and the original signal, the IMFs below the threshold are removed. Finally, SSA is introduced for secondary denoising, and the principal components are screened by the cumulative contribution rate of singular values after the singular value decomposition to eliminate the low-frequency oscillating noise components in the signal. The simulation results show that compared with other methods, the root mean square error (RMSE) and signal-to-noise ratio (SNR) of the signal processed by this paper's method are improved by 16.22% and 2.51%, respectively, at different noise levels. The engineering application results show that compared with other methods, the normalized Shannon entropy ratio (NSER) and noise suppression ratio (NSR) of the denoised signals of this paper's method are improved by 12.81% and 8.44%, respectively, which is of practical significance for denoising of signals of the bridge dynamic loading test.

In this study, large eddy simulation and FW-H acoustic analogy method were used to study the characteristics associated with cavitation flow field and sound field of organ pipe nozzles, focusing on evaluating the cavitation effect and the impact of cleaning noise on the cultivation of large yellow croaker.It is found that the turbulent boundary layer at the throat of the organ pipe nozzle is more obvious owing to the influence of the natural vibration effect which is conducive to the formation of cavitation groups, the average volume of cavitation produced by its work can reach 1.8 times when compared with that related to traditional convergent-divergent nozzles. In the external flow field, the narrower the jet trajectory outside the nozzle is, the more concentrated the cavitation cloud distribution will be. Its cavitation performance is better than that of the convergent-divergent nozzle in the near flow field area of 10 times the diameter of the pipe. The research results of cavitation sound field show.The self-oscillating organ pipe nozzle has no obvious peak noise in the sound sensitive band of large yellow croaker.Its working noise is mainly high frequency noise above 2000Hz.and presents a "maple leaf"-like directional distribution in the downstream plane. Considering the hearing curve of large yellow croakers, the total sound pressure level of the far-field monitoring point of the weighted organ pipe nozzle is more than 10 dB lower than that of the convergent-divergent nozzle, and its influence range on large yellow croakers remains within a radius of less than 0.7 m, suitable for the low-noise cleaning operations of cages for large yellow croakers in deep water culture.

A multibody dynamic model with compound-joint constrains was proposed to accurately simulate the vibration response of the seated human body. The human body was divided into five parts including the head and neck, upper trunk, middle trunk, lower trunk, and thighs and buttocks, and the composite hinge composted by sliding pair and rotational pair was used to connect the each parts of the body. The dynamic control equations of the seated body were derived based on the kinematic recursive relationships and the principle of virtual power. The nonlinear dynamic equations of the system were linearized to calculate the apparent mass (AM) and seat-to-head transmissibility (STHT). The square weighted sum of the normalized AM and STHT was defined as the objective function, and the spring and damping parameters in the model were identified by employing the publicly reported experimental data on the vibration of the seated human body. The vibration and modal characteristics of the seated human body was calculated based on the obtained multibody dynamics model. The numerical results show that the human body vibration response in this paper can match well with the experimental data, and the vibration modals can better reflect the actual motion characteristics of the seated human body.

Near-fault ground motions often exhibit distinct velocity pulse characteristics, which pose significant threats to arch bridges, particularly due to their pronounced spatial vibration response under seismic loading. To better understand the impact of near-fault ground motions on the seismic response of arch bridges, this study proposes a novel analytical approach called Seismic Meta-analysis (SMa). SMa is a secondary quantitative analysis method based on existing research data, offering a new pathway for seismic studies.This paper comprehensively outlines the SMa methodology, covering key aspects such as defining the analysis theme, collecting and classifying research data, constructing the analytical framework, applying quantitative theories, selecting metrics, and interpreting results. Using SMa, a comparative study is conducted to evaluate the effects of near-fault and non-near-fault ground motions on the seismic response of arch bridges. This analysis focuses on three dimensions: response differences, the extent of these differences, and the influence of specific factors. A total of 2,137 valid data sets from 98 studies were collected and analyzed to validate the feasibility of the SMa method, highlighting the distinctive effects of the two types of ground motions on the seismic response of arch bridges.The study reveals the following key findings: 1) SMa provides a fresh perspective for secondary analysis, free from the limitations of existing conclusions. It allows for the formulation of new research themes and offers supplementary insights to address gaps in current studies; 2) In the range of ground motion intensities between 0 and 0.6g, the differences in the seismic response of the main arch under near-fault and non-near-fault ground motions increase with intensity. However, these differences significantly decrease when the intensity exceeds 0.8g; 3) Near-fault ground motions have a more pronounced adverse effect on the displacement response and transverse seismic behavior of arch bridges; 4) Forward-directivity near-fault ground motions pose the greatest threat to arch bridges. Moreover, the impact of near-fault ground motions on transverse displacement shows a significant positive correlation with span length. Additionally, the study highlights the need for further investigation into the influence of factors such as bridge type, service life, and initial bridge conditions. Research on targeted seismic isolation and mitigation strategies for near-fault ground motions remains insufficient. This work represents the first application of Meta-analysis in the field of bridge seismic design and civil engineering, demonstrating broad practical value. 

Studying the dynamic mechanical characteristics and energy dissipation law of the lunar polar frozen lunar soil has important reference significance for the landing impact characteristics of the probe and the impact drilling sampling of the polar frozen lunar soil in the fourth phase of the lunar exploration project. In this paper, the frozen lunar soil prepared by basaltic simulated lunar soil is taken as the research object. The dynamic mechanical characteristics, dynamic failure morphology characteristics and energy dissipation law of simulated frozen lunar soil under different negative temperature, different water content are studied by using a Split Hopkinson Pressure Bar test device with a diameter of 50 mm under different impact loads. The results show that: (1)  When the temperature declined to -25°C, -45°C and -65°C, there is no compaction stage in the initial growth of the dynamic stress-strain curve, and the negative temperature has a significant effect on the deformation characteristics of the lunar soil simulant samples. The peak dynamic stress increases with the decrease of temperature and the increase of impact pressure, showing obvious temperature effect and strain rate effect. The decrease of temperature will weaken the transient temperature rise effect induced by impact load. There is a positive correlation between the dynamic strength growth coefficient ηd and the average strain rate, and the water content has a great influence on the simulated frozen lunar soil ηd. (2) Under the same impact load, the dynamic failure mechanism of the simulated frozen lunar soil are mainly block slip surface crushing failure,brittle fracture failure and shear boundary failure. (3)In the process of impact compression failure, the incident energy, reflection energy and absorption energy of the simulated frozen lunar soil all show a trend of rising first and then unchanged. The growth of the energy reflection coefficient is related to the negative temperature condition and the impact load. The energy absorption rate and average strain rate increase with the increase of damage degree.

To investigate the seismic performance and plastic hinge zone height of reinforced concrete (RC) double-column piers, four RC double-column piers with different pier heights were designed, and the horizontal cyclic reciprocating quasi-static loading test under constant axial force was carried out. The influence of damage state, failure mechanism, hysteresis performance and plastic hinge height of RC double-column pier was systematically analyzed. The test results show that with the increase of pier height, the failure mode of RC double-column pier changes from shear failure to bending-shear and bending failure, and the top and bottom of the pier develop obvious plastic damage areas, in particular, the plastic damage states of the top and bottom of the pier appear obvious asymmetry, and the damage states on both sides of tension and compression of each plastic damage area are also obviously different. The hysteresis curve of RC double-column piers is full, but it shows obvious stiffness and strength degradation. With the increase of pier height, the stiffness and strength of RC double-column piers decrease significantly, but there is no consistent change law in energy dissipation capacity, residual lateral displacement rate and ductility coefficient. The critical plastic hinge height of the RC double-column pier is positively correlated with the pier height, and the calculated results based on the existing inflection point assumption and the equivalent plastic hinge model (EPHM) are much lower than the measured value of the plastic hinge length of the RC double-column pier. The results of this paper can provide a reference for the further damage state and failure mechanism of RC double-column piers, as well as their seismic design.

The contact stiffness of the joint surface has a significant influence on the bolt loosening behavior. Therefore, the contact stiffness model of the joint surface is introduced, and the bolt loosening model considering the contact stiffness of the joint surface is established. The accuracy of the model is verified by comparing with the Nassar model and the bolt loosening test results. Based on the model established, the influence of parameters such as bolt size, initial preload, friction coefficient and pitch on the variation of critical transverse load and preload is analyzed in depth. The influence of bolt size, initial preload, friction coefficient and pitch on the critical transverse load and preload changes is analyzed. The results show that when the bolt size is M12, the critical transverse load increases by 23%, 66%, 75% and 8% with the increase of the initial preload, the underhead bearing friction coefficient, the thread friction coefficient and the pitch, respectively, and decreases by 20.4% with the increase of the half of the thread profile angle. The critical transverse load of M10 bolt increases first and then decreases with the increase of pitch, which is relatively increases by 3.5%. The critical transverse load of M8 bolt first remains unchanged and then decreases with the increase of pitch, which decreases by 1.1%. Under the same initial preload, the underhead bearing friction coefficient, the thread friction coefficient, the pitch and the half of the thread profile angle, the critical transverse load increases by 44%, 20%, 57%, 42% and 45.6%, respectively. The loosening rate decreases by 15%, 27.4%, 8.7% and 22.2% with the increase of the initial preload, the underhead bearing friction coefficient, the thread friction coefficient and the bolt size, respectively, and increases by 28.3%, 4.3% and 11.6% with the increase of the pitch, the half of the thread profile angle and transverse load amplitude, respectively. The study results provide an important reference for optimizing the design of bolted joints.

To investigate the nonlinear mechanical characteristics of the helical tube hydraulic inerter, a nonlinear dynamic model was established and its accuracy was verified through AMESim simulations and bench tests.The effects of helical tube structural parameters, working fluid properties, and hydraulic cylinder internal leakage on the inerter force were analyzed, and the damping force, inertial force characteristics, and failure states were discussed.The results show that the inerter force consists of inertial force, fluid parasitic damping force, and friction force, with the fluid parasitic damping force being the primary source of nonlinearity.The inerter force increases with the decrease in helical tube diameter, the increase in length, or the increase in surface roughness, while tube wall thickness has no significant effect.Compared to metal tubes, rubber hoses exhibit a damping effect on the force.High-density and high-viscosity working fluids increase the inerter force, but high viscosity also raises friction.Reducing the piston rod diameter increases the inerter force, whereas increasing internal leakage in the hydraulic cylinder decreases it.Excessive leakage leads to device failure.The findings provide a theoretical basis for the optimal design of hydraulic inerters.

Under the action of complex environmental loads, performance degradation of space grid structures is severe to cause sharp increase in risks of their safe service life.Here, mechanical response laws of grid structures under different design parameters were explored to perform probabilistic safety assessment of structures based on reliability.A 2D orthogonal flat plate space grid structure model was established using the software ABAQUS, and its stress and displacement changes under different height-span ratios, column spacings and corrosion rates were studied.Through simulation, it was shown that with increase in height-span ratio, the maximum tensile stress and displacement gradually decrease but their drop rates are gradually smaller, while the maximum compressive stress firstly decreases and then slightly increases; if height of space grid structure increases from 3.5 m to 6.3 m, the maximum displacement decreases by 53.66%; increase in column spacing causes the maximum stress and displacement increase, but their growth rates are gradually smaller; under grid space structure height of 3.5 m, column spacing increases from 4.5 m to 13.5 m, the maximum displacement increases by 22.63%; increase in corrosion rate causes slow increase in maximum stress and displacement, and effects of corrosion on structural stress is a gradual accumulation process, which does not suddenly cause a sharp drop of structural performance.Furthermore, Latin hypercube sampling method was used to evaluate the probability of structural failure under effects of multidimensional uncertain parameters, taking the allowable deflection specified in “Technical Specifications for Space Grid Structures” as the evaluation criterion.The results showed that under H1L2 working condition of 3.5 m structure height and 9.0 m column spacing, the failure probability without corrosion is 0.27%; when corrosion rate is 40.00%, the failure probability increases to 22.76%.

The wavenumber-frequency spectrum is an important statistical tool for describing the characteristics of turbulent boundary layer wall-pressure fluctuations. To further understand the common features of TBL pressure fluctuations and thereby support the construction of predictive models, research on the normalization of the TBL pressure fluctuation wavenumber-frequency spectrum is necessary. Initially, based on a compressible TBL pressure fluctuations wavenumber-frequency spectrum prediction model derived from the Lighthill equation, a normalization method for the wavenumber-frequency spectrum was established through source term optimization. Then, experiments were conducted in a low-speed wind tunnel using a flat plate. Near-wall velocity distribution characteristics were obtained using a hot-wire anemometer to support the construction of the normalization method; surface array were employed to obtain the TBL pressure fluctuation auto-spectrum and wavenumber-frequency spectrum characteristics under different wind speeds. Finally, the constructed normalization method for the wavenumber-frequency spectrum was validated using experimental data. The study demonstrates that reasonable optimization of the source terms in the predictive model can lead to the construction of a normalization method for the wavenumber-frequency spectrum. Surface arrays effectively measure the TBL pressure fluctuation auto-spectrum as well as the wavenumber-frequency spectrum, accurately reflecting the relevant characteristics of TBL pressure fluctuations. Normalizing the wavenumber-frequency spectrum verified the applicability of the normalization method, suggesting that the normalized wavenumber-frequency spectrum is independent of factors such as Mach number and Reynolds number. This study can provide theoretical support for research on flow-induced noise issues in engineering fields such as aviation, maritime, and high-speed rail.

The floating offshore wind turbine (FOWT) has strong background response due to overall sway, which presented in the frequency domain as the peak response being dominated by the excitation frequency and varying with the changing of load frequency.The frequency imbalance occurs when using traditional tuned mass damper (TMD) for vibration control, and resulting in poor performance.A magnetorheological elastomer-pounding tuned mass damper (MRE-PTMD) was designed and proposed for semi-active control of FOWT.In this device, the stiffness adjustable characteristic of MRE was utilized to achieve real-time adjustment of damper frequency through semi-active control technology, maintaining optimal control of the FOWT.At the same time, the viscoelastic limiting device was introduced to protect the MRE material and realize the collision energy dissipation.Taking the barge type FOWT as an example, a 17 degrees of freedom dynamic equation including the control device was established to study its vibration reduction performance and parameter influence under the combined action of wind and waves, and compared with traditional TMD.The results show that the proposed control device can adjust the control parameters of the damper in adaptive manner through real-time tracking of the structural response, and has better vibration reduction performance and adaptability compared to traditional TMD.Increasing the mass ratio of dampers is an effective way to improve the performance of MRE-PTMD.By designing the damper mass ratio and collision parameters reasonably, MRE protection and device miniaturization can be achieved without significantly affecting the vibration reduction effect.

To investigate the impact of underfilled grouting defects on the seismic performance of prefabricated bridge piers, produced three groups of grouting sleeve connectors specimens and carry out pull-out tests. According to the tests results, cast-in-place single-column pier, fully grouted assembled single-column pier and assembled single-column pier with grouting defect were designed as specimens and the pseudo-static tests were carried out. In addition, verified finite element pier models were established, and an extended parametric analysis was conducted regarding the length, location and quantity of the grouting defects. The results showed that: when the length of grouting defects in grouted sleeve connections exceeds 2.5 times the diameter of the reinforcement, the damage mode will change; the use of grouted sleeve connections will reduce the ultimate bearing capacity of the abutment specimens by 6.8%, and grouting defects will reduce the unloaded stiffness of the structure. In order to make the existence of grouting defects of the bridge pier still have sufficient seismic performance, should ensure that the grouting defects of the length of less than 2 times the diameter of the rebar, grouting defects in the number of sockets accounted for less than 40% of the defects do not appear in the middle of the assembly end and the end of the defects, this time, assembly of a single-column pier of cumulative hysteresis dissipation of the reduction in the amount of energy can be less than 10%.

Traditional anomaly detection methods suffer from limited accuracy due to their failures to capture both long- and short-term temporal patterns, neglect of sensor spatial correlations, and poor handling of missing data. This paper proposes T2MS-TADM (Transformer-TCN Multi-Scale Temporal Anomaly Detection Model), a novel method for multivariate time series anomaly detection tailored to vibration data with complex spatiotemporal characteristics. A dynamic spatiotemporal graph is constructed using graph neural networks, integrating temporal attention, differential attention, and spatial attention layers to capture long-term trends, short-term fluctuations, and spatial topological features of the vibration data. The local receptive fields of TCNs detect transient anomalies, while the Transformer’s global attention captures long-range dependencies. An end-feature concatenation strategy enhances multi-scale detection performance. To improve robustness under data loss scenarios caused by network instability, we propose a variable-length mask block generation method, which simulates realistic missing data patterns and optimizes masking strategies to preserve critical temporal information. Experiments on four public datasets (MSL, SMAP, etc.) achieve an average F1 score of 0.934, outperforming mainstream methods by 4.75%. On our in-house vehicle vibration dataset VAD-LSC, the model achieves an F1 score of 0.913. Results demonstrate that T2MS-TADM effectively captures complex spatiotemporal dynamics and exhibits robustness in the face of missing data, providing reliable technical support for industrial equipment anomaly detection.

Pump-turbine achieve precise grid response in pumped storage power plants by rapidly and frequently switching operating conditions.However, prolonged operation under variable conditions affects the unit’s hydraulic efficiency and structural performance.This study investigates a Francis pump-turbine under power generation mode during load-increasing conditions, employing the SST k-ω turbulence model and fluid-structure interaction method to resolve the internal flow and structural fields.The results reveal that the dominant pressure pulsation frequency in the runner passage is 20.00fn, while in the vaneless region, the primary frequencies are single blade frequency of the runner 9.00fn and double blade frequency of the runner 18.00fn (fn is runner rotating frequency).When the load is below 60%, blade inlet attack angles (ranging from 8.26°-18.08°) induce circumferential vortices, horseshoe vortices, and trailing-edge vortices within the runner domain, generating high-amplitude pressure pulsation regions (0.017-0.023).In contrast, when the load exceeds 60%, vortex core breakdown attenuates the intensity of pressure pulsations.Regarding structural response, the average deformation of the blade’s crown and band decreases along the runner passage (with differences of 7.6 μm and 5.3 μm between the inlet and outlet, respectively).Certain nodes in the crown and band are influenced by fixed constraint zones, resulting in significantly higher mean equivalent stress compared to unconstrained locations.Additionally, blade deformation increases from the crown and band toward the center, reaching a peak, while equivalent stress follows an inverse spatial distribution.The coupled analysis of the flow and structural fields reveals a linear positive correlation between average blade deformation and torque, whereas the average equivalent stress is linearly negatively correlated with flow rate.The blade deformation exhibits a linear correlation with the moment, and the equivalent stress in the middle third region of the blade shows a linear correlation with the flow rate.In contrast, the equivalent stresses in the front third and rear third regions of the blade demonstrate cubic and quadratic correlations with the flow rate, respectively.

In the construction of large underground tunnel complexes, auxiliary hole blasting faces the challenge of excessive vibration speeds. To control the vibration of auxiliary holes blasting, a long-short delay time cooperative blasting technology is proposed. This technology achieves precise initiation sequencing of boreholes within the same row based on the maximum allowable number of holes per delay, categorizing delay times into intra-row delays (intervals between adjacent delays within the same row) and inter-row delay (intervals between adjacent rows). Building on Anderson's theory, a vibration waveform superposition model was established to analyze the field-measured single-hole vibration waveforms. Optimal delay times were determined based on the safety vibration velocity threshold and the delay range determined through single-free-surface hole-by-hole blasting experiments. Application in a tunnel project demonstrated that when the intra-row delay was set to 8 ms and the inter-row delay to 40 ms, the peak velocity of auxiliary hole blasting was 2.57 cm•s-1—below the safety threshold of 3 cm•s-1—while the hole utilization rate attained 90.3%. This technology ensures blasting efficiency while realizing vibration control and provides theoretical support for the precision design of tunnel blasting parameters.

Here, to obtain a reasonable limit value for deflection-span ratio of a large-span highway suspension bridge, a certain domestic suspension bridge under construction was taken as the study object.Firstly, the sensitivity analyses for structure and gravity stiffnesses of different components were performed with the finite element method to establish the stiffness regulation method.Secondly, taking driving safety and driving comfort as evaluation indexes, stiffness sizes were adjusted for multi-working condition vehicle-bridge analysis to obtain range of stiffness values exceeding limit values of driving safety and driving comfort.Finally, the stiffness reduction amplitude was reduced until driving safety and driving comfort results could reach their limit values and the bridge deflection-span ratio limit value could be obtained based on driving performance using reverse deduction.The study results showed that vertical structural stiffness of suspension bridge is mainly controlled by main beam and main cable, while its lateral structural stiffness is mainly controlled by main beam and bridge tower; reducing structural stiffness and gravity stiffness of main beam and main cable can more obviously affect the overall stiffness, but their affecting degrees are different; limit values for vertical and lateral deflection-span ratios of main beam of a super large-span highway suspension bridge are approximately 1/150 and 1/80, respectively under conditions to satisfy driving safety and driving comfort.

In order to solve the problems faced by the existing intelligent fault diagnosis models in processing multi-channel signals, such as insufficient generalization ability, relying on artificial feature design and weak cross-channel correlation modeling, this paper proposed an end-to-end multi-channel signal adaptive diagnosis model based on TCN-Transformer. Through the cascade architecture of Time Convolutional Network (TCN) and Transformer, the model constructed a collaborative learning mechanism of local feature extraction and global dependency modeling: the TCN module used causal convolution to capture the local time-frequency mode of signals layer by layer, and its residual connection designed effectively alleviates the information attenuation of the deep network. In the feature recombination stage, the Unidirectional Patch (UDP) sequential marking method was proposed to cut the multi-channel timing signal into a high-dimensional fragment sequence with position coding, which avoided the boundary distortion problem of the traditional block strategy. In the Transformer coding layer, the channel attention mechanism and multi-head self-attention were innovatively integrated to form a hybrid attention module. This module simultaneously captures channel-wise features and positional relationships, thereby enhancing complementary representations among different sensor signals. Experiments show that the model achieves 98% recognition accuracy in the multi-sensor diagnostic task of planetary gearbox.

Tailings dam failures exhibited high suddenness and destructive power, often causing severe casualties, ecological damage, and economic losses. The failure process was difficult to intervene in, and theoretical analyses and simulations yielded uncertain results. Typical cases provided empirical references of significant value for disaster prevention, emergency response, and post-disaster recovery. This study examined three major failures—Mount Polley (Canada), Fundão (Brazil), and Feijão I (Brazil)—and analyzed 379 cases with complete information from 1915 to 2025. It discussed construction methods, causal factors, monitoring and regulation, inundation ranges, and remediation strategies. Results showed: (1) upstream dam failures frequently resulted from management deficiencies and extreme external factors rather than inherent flaws in the method; (2) monitoring and early warning systems failed in all three cases, while aerial and satellite remote sensing could serve as important supplements; (3) safety regulation should cover the entire life cycle, with strict control of design changes during construction; (4) released tailings volume correlated with dam height and storage capacity, while downstream topography determined inundation range; (5) there was no effective post-failure intervention, highlighting the need for decision-support tools to enhance emergency efficiency. The findings offer insights for scientific management, disaster prevention, and emergency preparedness of tailings storage facilities in China.

Magnetorheological dampers (MRDs) with asymmetric damping characteristics, defined by low compression and high extension, are critical for effective vibration damping and shock mitigation. However, these characteristics introduce significant modeling challenges and limit applications. So, a parameterized model was developed. The mechanism responsible for asymmetric force generation in conical flow channel magnetorheological dampers (CFC-MRD) was examined. Experimental measurements conducted under varying excitation displacements and driving currents validated the presence of asymmetric damping force output. An advanced asymmetric Bouc-Wen model, featuring tunable forward and reverse hysteresis operator parameters, was designed to accurately describe asymmetric characteristics. The proposed model achieved a 78.07% improvement in accuracy for identifying asymmetric features compared to conventional symmetric models. This work establishes a reliable framework for modeling the asymmetric mechanical behavior of MRDs.

In order to investigate the damage of aero-engine blades under high-temperature environments when subjected to foreign object impacts, based on the air gun experimental setup, this paper puts forward an experimental scheme for simulating high-temperature and high-speed impact damage on aero-engine blades, which makes up for the shortcomings of the current blade foreign object impact experimental technology. The proposed scheme was applied to conduct impact tests on titanium-aluminum alloy low-pressure turbine blades at room temperature using steel and ceramic projectiles, as well as steel projectile impacts at high temperature, and the resulting impact damage patterns of the blades were obtained. The experimental results indicate that the proposed high-temperature and high-speed impact test scheme for blades is feasible and yields good reproducibility, confirming the reliability of the experimental scheme. The blade surface develops a circular pit damage after impact, and when the impact velocity reaches a certain threshold, cracks form on the backside of the impact point. The cracks propagate from the point of impact to the edge of the blade. Owing to the inferior mass of ceramic projectiles compared to steel projectiles of equivalent diameter, coupled with the intrinsic fragility and susceptibility to shattering of ceramic materials, the impact of ceramic projectiles results in the fragmentation and consequently a partial loss of energy. As a result, the critical velocity for steel projectiles to cause blade cracking is significantly lower than that for ceramic projectiles at room temperature. Experimental results from the quasi-static tensile testing of titanium-aluminum alloy materials at both room temperature and high temperature indicate that the material exhibits enhanced plasticity at high temperature. Consequently, under high temperature impact scenarios, the critical velocity for steel projectiles to cause blade cracking is increased by approximately 30% when compared to room temperature conditions. Moreover, the damage pattern of the blade gradually shifts from mere pit damage to single crack damage, and eventually evolves into diffusive multi-crack damage as the impact energy increases.

With the implementation of the fifth edition of the Seismic ground motion parameter zonation map of China, the seismic fortification system has been upgraded from a traditional three-level to a more comprehensive four-level framework. To systematically evaluate the seismic performance of buckling-restrained braced steel frames under different seismic demand levels, a 9-story prototype structure with a seismic fortification intensity of 8-degree was designed, and a nonlinear numerical model was developed on the OpenSees platform. Nonlinear time-history analyses were conducted to investigate the peak responses, residual deformations, and brace behavior of the structure. Based on this, a fragility analysis was further conducted using incremental dynamic analysis to quantify the probability of structural damage under varying earthquake intensities. Results indicate that the structure meets the requirements of the three-level fortification objectives. Under extremely rare earthquakes, base shear increases by approximately 60% compared to rare earthquakes, the maximum inter-story drift angle reaches 1.6 times the code limit for rare earthquakes, and overall lateral deformation is 2.24 times greater, indicating a significantly elevated collapse risk. Residual drift becomes notable starting from the fortification-level earthquake, with an average of about 0.25%. Under rare and extremely rare earthquakes, residual deformations extend upward from lower stories, with most stories exceeding the 0.5% repair threshold. While peak drift becomes more concentrated with increasing seismic intensity, residual drift tends to be more uniformly distributed. The braces begin to dissipate energy from the fortification-level earthquake onward, showing no failure risk under the first three seismic levels and a low risk even under extremely rare earthquakes. Under extremely rare earthquakes, the exceedance probability of complete structural damage increases significantly compared to rare earthquakes, reaching 32.61%, indicating a high risk of collapse.

As the size of wind turbine blades continues to increase, asymmetric loads have gradually become a key factor affecting the operational stability and safety of wind turbines. These asymmetric loads exhibit periodic characteristics, and over long-term operation, they can lead to repeated fatigue of components, increasing maintenance costs and potentially causing component failure or even turbine overturning. To address this challenge, this study proposes a model-free adaptive independent pitch control method based on Bayesian optimization. By using a Gaussian process model, the relationship between the objective function and control parameters is captured, enabling the optimization of controller parameters. Simulations using the FAST software on a 15 MW offshore wind turbine indicate that this method can effectively mitigate the periodic vibrations induced by asymmetric loads, significantly reduce load fluctuations, enhance the operational stability and safety of the wind turbine, and lower maintenance costs.

To ensure the stability and safe operation of industrial robot joints, accurately assessing the performance degradation of a harmonic reducer is crucial. Addressing the limitation of existing performance degradation assessment methods, which predominantly rely on a single signal and fail to capture key information throughout the degradation process, an adaptive feature fusion method based on genetic programming is proposed. By combining acoustic emission and micro-vibration sensor data, a multi-stage health indicator is constructed, which effectively reflects the health status of the harmonic reducer. First, multi-feature extraction is performed on the acoustic emission and micro-vibration signals, analyzing the monotonicity, correlation, prognosability, and robustness of the signal features. Next, the entropy weight method is used to linearly weight the various indicators, constructing a composite evaluation index. The optimal features are then selected based on the highest index scores. Finally, genetic programming is applied to fuse the optimal features, generating the final health indicator. Experimental results demonstrate that the constructed health indicator can accurately capture the damage inflection points at each degradation stage of the harmonic reducer. Compared to single features, the constructed indicator more effectively reveals the inherent near-monotonic trend of the damage evolution process, and performs superiorly in terms of monotonicity, prognosability, and robustness. It provides strong support for the preventive maintenance of the harmonic reducer.

In the existing traditional quadrangle courtyards dwellings with timber skeletons in Beijing, Mantou mortise joints are commonly used to connect beams and columns. In the research, the quasi-static tests on two 2/3 scale Mantou mortise joint specimens are conducted and finite element solid model using ABAQUS software is established. The numerical simulation results are compared and validated against experimental data on Mantou mortise joints. On this basis, a series of parameters analysis including vertical load, friction coefficient, transverse and longitudinal elastic moduli and strengths, as well as damage situation were conducted to investigate the rotational performance of the Mantou mortise joint. The results indicate that the failure modes of the Mantou mortise joints are tenon pullout, compression deformation at the tenon base, and pressure deformation near mortise from column end surface due to rockment of the column. An increase of vertical load enhances both the rotational moment and stiffness of the Mantou mortise joint. Under a vertical load of 24 kN, the Mantou mortise joint model demonstrates a maximum rotation capacity of 1.5 kN﹒m and a rotation stiffness of 101.4 kN﹒m/rad. A vertical force of 10 kN results in a 36.09% reduction in rotation stiffness and a 31.25% decrease in maximum rotation moment, compared to that of vertical force of 24 kN. Anda vertical force of 20 kN leads to a 7.89% reduction in rotation stiffness and a 12.50% decrease in maximum bending moment. An increase in the friction coefficient contributes to enhancement of rotational capacity of the Mantou mortise joint. The transverse elastic modulus of timber has minimal impact on the rotational stiffness of the Mantou mortise joint, However, it does affect the maximum rotation moment to a certain extent. The longitudinal elastic modulus has a negligible effect on the initial rotation stiffness and rotation capacity of the joint. The increase of transverse strength result in varying degrees of improvement in the rotation capacity of the Mantou mortise joint, along with corresponding increase of the rotation angle at maximum moment. Damaged tenon leads to varying degrees of reduction in the rotation capacity of the Mantou mortise joint. The study provide valuable references and theoretical foundations for the preservation and restoration of quadrangle courtyards dwelling with timber skeletons.