Pub Date : 2025-03-03DOI: 10.1016/j.soildyn.2025.109346
Hongxu Jin , Zhen Huang , Li Shi , Jiahao Wang , Bo Chen
Calcareous sands provide the foundational support for various marine infrastructures. In the harsh marine environment, earthquake or wave loads apply multidirectional cyclic shear stresses to the foundation soil. To explore the undrained multidirectional cyclic response of sand, a series of simple shear tests were performed on reconstituted sand specimens considering the effect of phase difference (θ). By comparing the results with those of siliceous sand under similar conditions, the behavior of calcareous sand under multidirectional cyclic loading became clear. The results demonstrated that calcareous sand shows a lower degree of cyclic instability compared to siliceous sand, corresponding to the weaker strain-softening observed in calcareous sand during monotonic shear tests. The trend in normalized pore water pressure evolution in siliceous sand exceeds that in calcareous sand. Furthermore, under multidirectional cyclic shear conditions, the liquefaction resistance decreases by 30 % in extreme cases, irrespective of sand type. The liquefaction resistance of calcareous sand surpasses that of siliceous sand. However, as the cyclic stress ratio decreases, the reverse trend is observed, regardless of the impact of θ. Subsequently, the possible causes of the above experimental phenomena are explored from the perspectives of shear modulus and energy dissipation.
{"title":"Comparative study of undrained cyclic behavior of calcareous and siliceous sands under multidirectional simple shear loading","authors":"Hongxu Jin , Zhen Huang , Li Shi , Jiahao Wang , Bo Chen","doi":"10.1016/j.soildyn.2025.109346","DOIUrl":"10.1016/j.soildyn.2025.109346","url":null,"abstract":"<div><div>Calcareous sands provide the foundational support for various marine infrastructures. In the harsh marine environment, earthquake or wave loads apply multidirectional cyclic shear stresses to the foundation soil. To explore the undrained multidirectional cyclic response of sand, a series of simple shear tests were performed on reconstituted sand specimens considering the effect of phase difference (θ). By comparing the results with those of siliceous sand under similar conditions, the behavior of calcareous sand under multidirectional cyclic loading became clear. The results demonstrated that calcareous sand shows a lower degree of cyclic instability compared to siliceous sand, corresponding to the weaker strain-softening observed in calcareous sand during monotonic shear tests. The trend in normalized pore water pressure evolution in siliceous sand exceeds that in calcareous sand. Furthermore, under multidirectional cyclic shear conditions, the liquefaction resistance decreases by 30 % in extreme cases, irrespective of sand type. The liquefaction resistance of calcareous sand surpasses that of siliceous sand. However, as the cyclic stress ratio decreases, the reverse trend is observed, regardless of the impact of θ. Subsequently, the possible causes of the above experimental phenomena are explored from the perspectives of shear modulus and energy dissipation.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"194 ","pages":"Article 109346"},"PeriodicalIF":4.2,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143548211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-03DOI: 10.1016/j.soildyn.2025.109336
Yihan Chai , Qi Zhang , Bin Yan , Wenxuan Zhu , Guanlin Ye
To address the challenges of extraction difficulties and penetration risks associated with traditional spudcan jack-up platforms, a new jack-up platform featuring a pile-leg mat foundation is proposed. The horizontal bearing capacity of hybrid foundations under the influence of dynamic loads is a critical factor that requires close attention. This research numerically examined the dynamic response of a hybrid foundation to horizontal cyclic loading on a sandy seabed. A user-defined subroutine was employed to incorporate the Cyclic Mobility (CM) model within Abaqus, facilitating the analysis of sand response under different densities. The horizontal cyclic bearing capacities of the foundation were investigated considering the effects of different loading conditions, sand density, and pile-leg penetration depth. Simulation results indicate that the cyclic loading amplitude, frequency, and load mode significantly influence the generation of soil excess pore water pressure (EPWP), subsequently affecting foundation displacement and unloading stiffness. Under cyclic loading, the loose sandy seabed shows the most pronounced fluctuations in EPWP and effective stress, leading to surface soil liquefaction. While surface soil in medium-dense and dense sand conditions remains non-liquefied, their effective stress still varies significantly. Increasing the pile-leg penetration depth enhances the foundation's horizontal bearing capacity while affecting its vertical bearing capacity slightly.
{"title":"Dynamic response of hybrid foundation for jack-up platform on sandy seabed under horizontal cyclic loading","authors":"Yihan Chai , Qi Zhang , Bin Yan , Wenxuan Zhu , Guanlin Ye","doi":"10.1016/j.soildyn.2025.109336","DOIUrl":"10.1016/j.soildyn.2025.109336","url":null,"abstract":"<div><div>To address the challenges of extraction difficulties and penetration risks associated with traditional spudcan jack-up platforms, a new jack-up platform featuring a pile-leg mat foundation is proposed. The horizontal bearing capacity of hybrid foundations under the influence of dynamic loads is a critical factor that requires close attention. This research numerically examined the dynamic response of a hybrid foundation to horizontal cyclic loading on a sandy seabed. A user-defined subroutine was employed to incorporate the Cyclic Mobility (CM) model within Abaqus, facilitating the analysis of sand response under different densities. The horizontal cyclic bearing capacities of the foundation were investigated considering the effects of different loading conditions, sand density, and pile-leg penetration depth. Simulation results indicate that the cyclic loading amplitude, frequency, and load mode significantly influence the generation of soil excess pore water pressure (EPWP), subsequently affecting foundation displacement and unloading stiffness. Under cyclic loading, the loose sandy seabed shows the most pronounced fluctuations in EPWP and effective stress, leading to surface soil liquefaction. While surface soil in medium-dense and dense sand conditions remains non-liquefied, their effective stress still varies significantly. Increasing the pile-leg penetration depth enhances the foundation's horizontal bearing capacity while affecting its vertical bearing capacity slightly.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"194 ","pages":"Article 109336"},"PeriodicalIF":4.2,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-03DOI: 10.1016/j.soildyn.2025.109339
Sepehr Rassoulpour, Mahmoud R. Shiravand, Mohammad Safi
The soil structure interaction (SSI) can severely affect the behavior of a structural system. This paper examines the impact of the SSI on the seismic performance of self-centering (SC) rocking piers. Finite element (FE) models of conventional reinforced concrete (RC) piers and SC rocking piers with and without energy dissipators are built and validated. The soil-foundation-structure interaction is modeled using the beam-on-nonlinear-Winkler-foundation (BNWF) approach, capturing the nonlinear behavior of soil. This approach is also validated, comparing the settlement and moment-rotation behavior of the numerical simulation and experimental results. Various scenarios, including different foundations and soil types, are considered. Nonlinear cyclic and dynamic analyses are performed. Three sets of fragility curves are obtained, assuming maximum drift, residual drift, and foundation settlement as engineering demand parameters (EDPs). The effect of earthquake frequency content and duration are also investigated. The results show that SC rocking piers can reduce settlements, but a relatively strong foundation is needed to carry out the expected seismic performance level and effectively reduce residual drifts.
{"title":"Effect of soil-structure interaction on seismic behavior of self-centering rocking piers supported on shallow foundations","authors":"Sepehr Rassoulpour, Mahmoud R. Shiravand, Mohammad Safi","doi":"10.1016/j.soildyn.2025.109339","DOIUrl":"10.1016/j.soildyn.2025.109339","url":null,"abstract":"<div><div>The soil structure interaction (SSI) can severely affect the behavior of a structural system. This paper examines the impact of the SSI on the seismic performance of self-centering (SC) rocking piers. Finite element (FE) models of conventional reinforced concrete (RC) piers and SC rocking piers with and without energy dissipators are built and validated. The soil-foundation-structure interaction is modeled using the beam-on-nonlinear-Winkler-foundation (BNWF) approach, capturing the nonlinear behavior of soil. This approach is also validated, comparing the settlement and moment-rotation behavior of the numerical simulation and experimental results. Various scenarios, including different foundations and soil types, are considered. Nonlinear cyclic and dynamic analyses are performed. Three sets of fragility curves are obtained, assuming maximum drift, residual drift, and foundation settlement as engineering demand parameters (EDPs). The effect of earthquake frequency content and duration are also investigated. The results show that SC rocking piers can reduce settlements, but a relatively strong foundation is needed to carry out the expected seismic performance level and effectively reduce residual drifts.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"194 ","pages":"Article 109339"},"PeriodicalIF":4.2,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-03DOI: 10.1016/j.soildyn.2025.109338
Chaofan Ren , Jue Wang , Daniel TW. Looi , Ming Hong
The tuned inertial damper (TID) is an inerter-based damper that has been widely used to reduce the vibration of structures in seismic engineering. Due to the mass amplification effect of inertial capacity, it has become an effective substitute for conventional tuned mass damper (TMD). The design parameters in the TID are generally H2-optimised, based on the assumption that the rigid structural foundation is excited by a stochastic white noise. However, the effect of soil-structure interaction (SSI) and the frequency dependence of the power spectral density model for stochastic ground motion are worth to be considered in the optimisation. In this regard, this paper establishes the equations of motion control for a single-degree-of-freedom (SDOF) structure equipped with a TID considering the SSI effect, and derives the mean-square value of the response of the SSI-SDOF-TID system with seismic excitation described by filtered Kanai-Tajimi (K-T) spectrum. Numerical optimisation is carried out by using a novel Nutcracker Optimisation Algorithm (NOA). The displacement, velocity and acceleration response reduction ratios of the concentrated mass supported by different soil conditions, as well as the optimal stiffness ratios and damping ratios of the corresponding TIDs, are compared to demonstrate the necessity of considering the SSI effect. Finally, the time-history responses of displacement, velocity, and acceleration of SSI-SDOF-TID system under artificial and natural seismic waves are analysed in soft soil conditions, and compared with SSI-SDOF systems. The parameter analysis shows that the optimal parameters of TID obtained for soft soil conditions with the same objectives are smaller than those of dense and medium soils, and the vibration control effect is the worst. The parameters of TID obtained from the optimisation of the same soil condition will be overestimated if the external excitation is simplified to white noise. The time-history response analysis of seismic waves in soft soil shows that the TID obtained by considering SSI has better vibration control performance.
{"title":"Optimal design and performance evaluation of a tuned inertial damper considering soil-structure interaction effects","authors":"Chaofan Ren , Jue Wang , Daniel TW. Looi , Ming Hong","doi":"10.1016/j.soildyn.2025.109338","DOIUrl":"10.1016/j.soildyn.2025.109338","url":null,"abstract":"<div><div>The tuned inertial damper (TID) is an inerter-based damper that has been widely used to reduce the vibration of structures in seismic engineering. Due to the mass amplification effect of inertial capacity, it has become an effective substitute for conventional tuned mass damper (TMD). The design parameters in the TID are generally H<sub>2</sub>-optimised, based on the assumption that the rigid structural foundation is excited by a stochastic white noise. However, the effect of soil-structure interaction (SSI) and the frequency dependence of the power spectral density model for stochastic ground motion are worth to be considered in the optimisation. In this regard, this paper establishes the equations of motion control for a single-degree-of-freedom (SDOF) structure equipped with a TID considering the SSI effect, and derives the mean-square value of the response of the SSI-SDOF-TID system with seismic excitation described by filtered Kanai-Tajimi (K-T) spectrum. Numerical optimisation is carried out by using a novel Nutcracker Optimisation Algorithm (NOA). The displacement, velocity and acceleration response reduction ratios of the concentrated mass supported by different soil conditions, as well as the optimal stiffness ratios and damping ratios of the corresponding TIDs, are compared to demonstrate the necessity of considering the SSI effect. Finally, the time-history responses of displacement, velocity, and acceleration of SSI-SDOF-TID system under artificial and natural seismic waves are analysed in soft soil conditions, and compared with SSI-SDOF systems. The parameter analysis shows that the optimal parameters of TID obtained for soft soil conditions with the same objectives are smaller than those of dense and medium soils, and the vibration control effect is the worst. The parameters of TID obtained from the optimisation of the same soil condition will be overestimated if the external excitation is simplified to white noise. The time-history response analysis of seismic waves in soft soil shows that the TID obtained by considering SSI has better vibration control performance.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"194 ","pages":"Article 109338"},"PeriodicalIF":4.2,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-28DOI: 10.1016/j.soildyn.2025.109305
Wuji Guo , Zhiping Zeng , Fushan Liu , Peicheng Li , Weidong Wang , Cheng Chang , Qiuyi Li , Ping Li
Rail transit-induced ground vibrations can significantly impact the environment and quality of life in surrounding areas. Accurately predicting the intensity of vibration sources induced by train operations is crucial for mitigating these adverse effects. This paper presents a new method for predicting vibration source intensity using train-track coupled dynamics (TTCD) and a generalized transfer function (GTF). In this method, the TTCD is employed to calculate the rail acceleration under train operations. Expanded the definition of traditional transfer functions, and the GTF is defined by replacing the Laplace transform in the transfer function with the Short-Time Fourier Transform (STFT) and Discrete Wavelet Packet Transform (DWPT), and it is calculated using finite element simulation results. Subsequently, the 1/3 octave vibration level and Z-weighted vibration level of the tunnel are estimated by substituting the rail response into the transfer function. The accuracy of the prediction method is validated through field tests conducted on Line 3 of the Changsha Metro. The results show that the prediction accuracy based on the DWPTTF is the highest, followed by the method based on STFTTF, with both methods being more accurate than the prediction based on FTTF and train-track-tunnel coupled dynamics. These findings demonstrate that the proposed method can effectively predict vibration source intensity, offering a valuable tool for engineers and researchers in the field of rail transit vibration analysis.
{"title":"Prediction method of train induced vibration source intensity based on generalized transfer function","authors":"Wuji Guo , Zhiping Zeng , Fushan Liu , Peicheng Li , Weidong Wang , Cheng Chang , Qiuyi Li , Ping Li","doi":"10.1016/j.soildyn.2025.109305","DOIUrl":"10.1016/j.soildyn.2025.109305","url":null,"abstract":"<div><div>Rail transit-induced ground vibrations can significantly impact the environment and quality of life in surrounding areas. Accurately predicting the intensity of vibration sources induced by train operations is crucial for mitigating these adverse effects. This paper presents a new method for predicting vibration source intensity using train-track coupled dynamics (TTCD) and a generalized transfer function (GTF). In this method, the TTCD is employed to calculate the rail acceleration under train operations. Expanded the definition of traditional transfer functions, and the GTF is defined by replacing the Laplace transform in the transfer function with the Short-Time Fourier Transform (STFT) and Discrete Wavelet Packet Transform (DWPT), and it is calculated using finite element simulation results. Subsequently, the 1/3 octave vibration level and Z-weighted vibration level of the tunnel are estimated by substituting the rail response into the transfer function. The accuracy of the prediction method is validated through field tests conducted on Line 3 of the Changsha Metro. The results show that the prediction accuracy based on the DWPTTF is the highest, followed by the method based on STFTTF, with both methods being more accurate than the prediction based on FTTF and train-track-tunnel coupled dynamics. These findings demonstrate that the proposed method can effectively predict vibration source intensity, offering a valuable tool for engineers and researchers in the field of rail transit vibration analysis.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"194 ","pages":"Article 109305"},"PeriodicalIF":4.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-28DOI: 10.1016/j.soildyn.2025.109323
Zhongxing Wang , Mei Liu , Mengyu Li , Hao Wu , Mingjie Liu , Xiang Yan , Qinghua Han
Responses of structures under coupled earthquake and wave-current actions are greatly influenced by the difference between occurrence times of earthquake and wave-current action. Aiming to obtain the most dangerous scenario of the structure (i.e. the maximum structural response) from underwater shaking table (UST) tests, the most unfavorable moment of shaking occurrence in UST tests was analytically investigated in this study through three steps. Firstly, analytical solutions for natural frequencies of structures submerged in water were proposed. Underpinned by the calculated frequencies, the time corresponding to the maximum responses of structures under earthquakes in still water (ES) was solved utilizing the mode superposition method. Secondly, simplified Morison equations were proposed to solve the time corresponding to maximum wave-current forces. Then, the time corresponding to the maximum responses of structures under wave-current (WC) action was solved by considering the time lag between excitations and responses. Thirdly, the calculation method for the most unfavorable moment of shaking occurrence in UST tests was proposed through comprehensive analyses of the theoretical results of structures under ES and WC conditions. Finally, underpinned by a numerical model, which can accurately reproduce the structural responses under coupled earthquake and wave-current (EWC) actions, all the new proposals were comprehensively validated, considering different parameters of structures and excitations. The results showed that the proposed analytical method has sufficient accuracy in determining the most unfavorable moment of shaking occurrence in UST tests. The analytical methods proposed in the current paper provided a firm basis for the design and implementation of UST tests.
{"title":"Analytical solutions for determining the most unfavorable moment of shaking occurrence in underwater shaking table tests","authors":"Zhongxing Wang , Mei Liu , Mengyu Li , Hao Wu , Mingjie Liu , Xiang Yan , Qinghua Han","doi":"10.1016/j.soildyn.2025.109323","DOIUrl":"10.1016/j.soildyn.2025.109323","url":null,"abstract":"<div><div>Responses of structures under coupled earthquake and wave-current actions are greatly influenced by the difference between occurrence times of earthquake and wave-current action. Aiming to obtain the most dangerous scenario of the structure (i.e. the maximum structural response) from underwater shaking table (UST) tests, the most unfavorable moment of shaking occurrence in UST tests was analytically investigated in this study through three steps. Firstly, analytical solutions for natural frequencies of structures submerged in water were proposed. Underpinned by the calculated frequencies, the time corresponding to the maximum responses of structures under earthquakes in still water (ES) was solved utilizing the mode superposition method. Secondly, simplified Morison equations were proposed to solve the time corresponding to maximum wave-current forces. Then, the time corresponding to the maximum responses of structures under wave-current (WC) action was solved by considering the time lag between excitations and responses. Thirdly, the calculation method for the most unfavorable moment of shaking occurrence in UST tests was proposed through comprehensive analyses of the theoretical results of structures under ES and WC conditions. Finally, underpinned by a numerical model, which can accurately reproduce the structural responses under coupled earthquake and wave-current (EWC) actions, all the new proposals were comprehensively validated, considering different parameters of structures and excitations. The results showed that the proposed analytical method has sufficient accuracy in determining the most unfavorable moment of shaking occurrence in UST tests. The analytical methods proposed in the current paper provided a firm basis for the design and implementation of UST tests.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"194 ","pages":"Article 109323"},"PeriodicalIF":4.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-27DOI: 10.1016/j.soildyn.2025.109308
Ying Ma , Jiabo Li , Dongsheng Wang , Jiahao Mi , Kuangyu Dai
The reinforced concrete (RC) columns eroded by chloride ions are more likely to be damaged under seismic loading. In this paper, a prediction method of hysteretic curve of corroded RC columns based on asymmetric Bouc-Wen-Baber-Noori (BWBN) model is proposed. Firstly, the effects of 13 control parameters on the asymmetric BWBN model are analyzed. Then, the test data of the quasi-static test of corroded RC columns are collected. The differential evolution algorithm of Bayesian theory is used to identify the parameters of the asymmetric BWBN model, and the prior distribution range of the parameters is discussed. Through the correlation analysis between the parameters of the corroded RC columns and the parameters of the asymmetric BWBN model, it is found that there is a poor correlation between the both parameters, and the Bayesian neural network optimized by the Gaussian process is used to establish the relationship between the two parameters. The results show that by inputting the parameters including corrosion ratio of corroded column members, the well-trained Bayesian neural network is used to predict the parameters of asymmetric BWBN model, and then the hysteresis curve of corroded RC columns under the earthquake can be reasonably predicted by asymmetric BWBN model. And inputting the corrosion ratio directly is more accurate in predicting than inputting other design parameters that consider the impact of correction.
{"title":"Probabilistic prediction of hysteretic curves of corroded reinforced concrete columns based on Bayesian theory","authors":"Ying Ma , Jiabo Li , Dongsheng Wang , Jiahao Mi , Kuangyu Dai","doi":"10.1016/j.soildyn.2025.109308","DOIUrl":"10.1016/j.soildyn.2025.109308","url":null,"abstract":"<div><div>The reinforced concrete (RC) columns eroded by chloride ions are more likely to be damaged under seismic loading. In this paper, a prediction method of hysteretic curve of corroded RC columns based on asymmetric Bouc-Wen-Baber-Noori (BWBN) model is proposed. Firstly, the effects of 13 control parameters on the asymmetric BWBN model are analyzed. Then, the test data of the quasi-static test of corroded RC columns are collected. The differential evolution algorithm of Bayesian theory is used to identify the parameters of the asymmetric BWBN model, and the prior distribution range of the parameters is discussed. Through the correlation analysis between the parameters of the corroded RC columns and the parameters of the asymmetric BWBN model, it is found that there is a poor correlation between the both parameters, and the Bayesian neural network optimized by the Gaussian process is used to establish the relationship between the two parameters. The results show that by inputting the parameters including corrosion ratio of corroded column members, the well-trained Bayesian neural network is used to predict the parameters of asymmetric BWBN model, and then the hysteresis curve of corroded RC columns under the earthquake can be reasonably predicted by asymmetric BWBN model. And inputting the corrosion ratio directly is more accurate in predicting than inputting other design parameters that consider the impact of correction.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"193 ","pages":"Article 109308"},"PeriodicalIF":4.2,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-27DOI: 10.1016/j.soildyn.2025.109322
Lei Hu , Yingmin Li , Weihao Pan , Hongwu Yang , Shuyan Ji
This study aims to develop a damping scaling factor (DSF) model for scaling 5%-damped vertical elastic response spectra to other damping ratios for subduction earthquakes in both offshore (S-net) and onshore (K-NET and KiK-net) regions of Japan. To achieve this, more than 36,000 onshore records and 3400 offshore records from subduction earthquakes were used to develop the DSF model. The proposed DSF model is a function of moment magnitude, rupture distance, damping ratio, and station type, employing a linear function of ln(β) to differentiate between onshore, offshore buried, and offshore unburied ground motions. The coefficients of the DSF model were determined using Bayesian inference with Integrated Nested Laplace Approximation (INLA). The DSF model is applicable to subduction earthquake scenarios with moment magnitudes ranging from 5.5 to 9.1, rupture distances up to 1000 km, and damping ratios between 0.5 % and 30 %. The results show significant differences among onshore, offshore buried, and offshore unburied ground motions across most spectral periods at various damping ratios. An intersection point occurs near a spectral period of 1 s at the same damping ratios, where opposing variation trends are observed for magnitude and distance scaling before and after this point. Additionally, a standard deviation model for the proposed DSF model was developed using a cubic function of ln(β/5) for onshore, buried, and unburied ground motions. Compared to the observed standard deviation, the proposed model effectively captures the observed trends. The proposed DSF model can be effectively used to scale 5%-damped onshore and offshore GMMs to other GMMs with damping ratios ranging from 0.5 % to 30 % for subduction earthquakes. This is important for implementing probabilistic seismic hazard assessments, seismic design, and seismic zoning in both offshore and onshore regions of Japan.
{"title":"A damping scaling factor model for vertical elastic response spectra from subduction earthquakes in offshore and onshore regions of Japan","authors":"Lei Hu , Yingmin Li , Weihao Pan , Hongwu Yang , Shuyan Ji","doi":"10.1016/j.soildyn.2025.109322","DOIUrl":"10.1016/j.soildyn.2025.109322","url":null,"abstract":"<div><div>This study aims to develop a damping scaling factor (DSF) model for scaling 5%-damped vertical elastic response spectra to other damping ratios for subduction earthquakes in both offshore (S-net) and onshore (K-NET and KiK-net) regions of Japan. To achieve this, more than 36,000 onshore records and 3400 offshore records from subduction earthquakes were used to develop the DSF model. The proposed DSF model is a function of moment magnitude, rupture distance, damping ratio, and station type, employing a linear function of ln(<em>β</em>) to differentiate between onshore, offshore buried, and offshore unburied ground motions. The coefficients of the DSF model were determined using Bayesian inference with Integrated Nested Laplace Approximation (INLA). The DSF model is applicable to subduction earthquake scenarios with moment magnitudes ranging from 5.5 to 9.1, rupture distances up to 1000 km, and damping ratios between 0.5 % and 30 %. The results show significant differences among onshore, offshore buried, and offshore unburied ground motions across most spectral periods at various damping ratios. An intersection point occurs near a spectral period of 1 s at the same damping ratios, where opposing variation trends are observed for magnitude and distance scaling before and after this point. Additionally, a standard deviation model for the proposed DSF model was developed using a cubic function of ln(<em>β</em>/5) for onshore, buried, and unburied ground motions. Compared to the observed standard deviation, the proposed model effectively captures the observed trends. The proposed DSF model can be effectively used to scale 5%-damped onshore and offshore GMMs to other GMMs with damping ratios ranging from 0.5 % to 30 % for subduction earthquakes. This is important for implementing probabilistic seismic hazard assessments, seismic design, and seismic zoning in both offshore and onshore regions of Japan.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"193 ","pages":"Article 109322"},"PeriodicalIF":4.2,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143508937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-26DOI: 10.1016/j.soildyn.2025.109303
Shupei Chen , Duofa Ji , Changhai Zhai , Hao Ni , Lili Xie
Previous studies have shown that existing buildings significantly affect ground motion at the foundation level due to seismic interaction between the building and the underlying site. The modification induced by the existing building is quantified by the transfer function, defined as the Fourier spectral ratio between the foundation motion and the free-field motion. This study focuses on evaluating the building-induced modification of ground motion using a convolutional encoder-decoder neural network (CEDNN) model. To this end, a series of numerical simulations were performed, including 2565 finite element models for the structure-soil system and the free-field condition. Using the simulation results as a database, the CEDNN model was developed to rapidly predict the transfer function. The predictive performance of the proposed model was then compared with that of other neural network models. The results indicate that the CEDNN model achieves high predictive accuracy, with mean absolute errors of 0.045 and a coefficient of determination of 0.967. Overall, the CEDNN model provides an efficient tool for predicting building-induced modifications of ground motion.
{"title":"Prediction of the existing building-induced modifications of ground motion at layered sites using convolutional encoder-decoder neural networks (CEDNN)","authors":"Shupei Chen , Duofa Ji , Changhai Zhai , Hao Ni , Lili Xie","doi":"10.1016/j.soildyn.2025.109303","DOIUrl":"10.1016/j.soildyn.2025.109303","url":null,"abstract":"<div><div>Previous studies have shown that existing buildings significantly affect ground motion at the foundation level due to seismic interaction between the building and the underlying site. The modification induced by the existing building is quantified by the transfer function, defined as the Fourier spectral ratio between the foundation motion and the free-field motion. This study focuses on evaluating the building-induced modification of ground motion using a convolutional encoder-decoder neural network (CEDNN) model. To this end, a series of numerical simulations were performed, including 2565 finite element models for the structure-soil system and the free-field condition. Using the simulation results as a database, the CEDNN model was developed to rapidly predict the transfer function. The predictive performance of the proposed model was then compared with that of other neural network models. The results indicate that the CEDNN model achieves high predictive accuracy, with mean absolute errors of 0.045 and a coefficient of determination of 0.967. Overall, the CEDNN model provides an efficient tool for predicting building-induced modifications of ground motion.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"193 ","pages":"Article 109303"},"PeriodicalIF":4.2,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143487074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-25DOI: 10.1016/j.soildyn.2025.109331
Hui Shen , Yaqun Liu , Xinping Li , Haibo Li , Liangjun Wang , Wenxu Huang
Both the topography and stratigraphy of slopes significantly affect the ground motions of slopes during earthquakes, and oblique incidence of seismic waves can further aggravate amplification. This study aims to parametrically explore the combined effects of the topography and stratigraphy of layered rock slopes on seismic amplification subjected to vertical and oblique propagating waves and provide qualitative and quantitative insight into this phenomenon. The spectral element method used to obtain the seismic response of slopes is introduced and verified by two examples. The influences of the slope angle, material properties of the layers, surface layer conditions, and incident angle of the seismic waves on the seismic amplification are then investigated. The results indicate that the peak horizontal and vertical amplification factors for layered rock slopes subjected to vertical and oblique incidence of seismic waves are in the ranges of 1.3–7.6 and 0.3–5.2, respectively. Among the various factors, the thickness and shear wave velocity of the surface layer of slopes have the greatest influence on the amplification effect, especially for obliquely incident waves. At oblique incidence, the maximum horizontal and vertical normalized acceleration amplification factors for the soft-surface-layer slope are 4.4 and 7.4 times greater than those for the hard-surface cases, respectively, whereas at vertical incidence, these values are only 2.8 and 4.3, respectively. When the impedance ratio between the surface layer and the underlying layer is 0.5 (i.e., the soft surface layer), unusual vertical amplification is observed where the maximum vertical amplification factor reaches 5.2. The findings of this study may provide useful reference and guidance for the seismic design of slope engineering and building structures near slopes.
{"title":"The combined amplification effects of topography and stratigraphy of layered rock slopes under vertically and obliquely incident seismic waves","authors":"Hui Shen , Yaqun Liu , Xinping Li , Haibo Li , Liangjun Wang , Wenxu Huang","doi":"10.1016/j.soildyn.2025.109331","DOIUrl":"10.1016/j.soildyn.2025.109331","url":null,"abstract":"<div><div>Both the topography and stratigraphy of slopes significantly affect the ground motions of slopes during earthquakes, and oblique incidence of seismic waves can further aggravate amplification. This study aims to parametrically explore the combined effects of the topography and stratigraphy of layered rock slopes on seismic amplification subjected to vertical and oblique propagating waves and provide qualitative and quantitative insight into this phenomenon. The spectral element method used to obtain the seismic response of slopes is introduced and verified by two examples. The influences of the slope angle, material properties of the layers, surface layer conditions, and incident angle of the seismic waves on the seismic amplification are then investigated. The results indicate that the peak horizontal and vertical amplification factors for layered rock slopes subjected to vertical and oblique incidence of seismic waves are in the ranges of 1.3–7.6 and 0.3–5.2, respectively. Among the various factors, the thickness and shear wave velocity of the surface layer of slopes have the greatest influence on the amplification effect, especially for obliquely incident waves. At oblique incidence, the maximum horizontal and vertical normalized acceleration amplification factors for the soft-surface-layer slope are 4.4 and 7.4 times greater than those for the hard-surface cases, respectively, whereas at vertical incidence, these values are only 2.8 and 4.3, respectively. When the impedance ratio between the surface layer and the underlying layer is 0.5 (i.e., the soft surface layer), unusual vertical amplification is observed where the maximum vertical amplification factor reaches 5.2. The findings of this study may provide useful reference and guidance for the seismic design of slope engineering and building structures near slopes.</div></div>","PeriodicalId":49502,"journal":{"name":"Soil Dynamics and Earthquake Engineering","volume":"193 ","pages":"Article 109331"},"PeriodicalIF":4.2,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143478950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}