Table 1 - uploaded by Jianli Yuan
Content may be subject to copyright.
Source publication
The dynamic behavior is an important index to evaluate the seismic property and damage of ancient pagodas. Combining with the research of protection technology on Huqiu pagoda, this paper discusses the key points, schemes, and measures of improving test efficiency for applied ambient random excitation technology to determine the dynamic behavior of...
Context in source publication
Similar publications
This paper aims at investigating the behavior of masonry buildings strengthened with concrete shear walls. To this end, a masonry wall with openings extracted from an individual two-storey masonry building is modeled using ANSYS finite element software. A number of nonlinear static analyses were conducted on the model. The nonlinear behavior of the...
Citations
... The performances of these historic pagodas' were examined in accordance with the dynamic characteristic parameters after dynamic tests were conducted to ascertain their dynamic features. The Songjiang Pagoda's dynamic properties were examined, and the damage sites and intensity of the pagoda were assessed using the difference in modal information before and after damage [19][20][21]. ...
This study provides a comparison of results from dynamic centrifuge tests and a finite element analysis model to confirm the behavior of a representative Korean stone pagoda cultural heritage structure against earthquakes. The indirect stiffness or physical state of the structure was estimated by measuring the natural frequency of the masonry stone pagoda. The actual natural frequency of the stone pagoda was measured to be 4.5 Hz. It was determined to have a lower natural frequency than other stone pagodas of similar size. For the experiment, a dynamic centrifugal separator test was performed on a 1/15 model. Data from an actual earthquake record, the Ofunato earthquake, were used, with various maximum acceleration levels ranging from 0.069 g to 0.424 g. In order to confirm the accuracy of the finite element analysis model, the measured natural frequency of the masonry stone pagoda was compared with the modal analysis of the finite element model. When the data obtained from the experiment and the PGA (peak ground acceleration) of the FEM analysis with a complex masonry stone pagoda using a validated model result were compared, it was found to have a low average error rate of 13%. This shows that structural behavior can be predicted for similar masonry stone pagoda structures using finite element method analysis in the future.
... For modal identification, the frequency response function (FRF) is used, and this is defined as a ratio of the output response and input force as follows (Yuan et al., 2005): ...
... The power spectrum of the input signals is considered as a constant. Subsequently, the FRF is estimated as follows (Yuan et al., 2005): ...
Train-induced vibration exhibits a potential dynamic impact on historic buildings and especially on those with high historical and cultural value. Under the long-term reciprocating load of train vibrations, structural fatigue damage can occur, and thus, a significant problem involves effectively evaluating and mitigating vibration impact on historic buildings while developing a rail transit system. In the present study, train-induced vibration impact and dynamic behavior of Probhutaratna pagoda in the suburb of Beijing, which has a history of approximately 1000 years, was investigated. To examine the dynamic behavior of the Probhutaratna pagoda and determine the weakest position in its architectural damage under train loads, its dynamic characteristics were measured. The free vibration modes were identified based on the dynamic measurement results. Subsequently, a finite element (FE) model of the Probhutaratna pagoda was constructed and the models and train-induced structural responses were compared with measured results. Finally, the structural dynamic responses to moving train loads were analyzed in detail. The results indicate the following conclusions. (1) The dominant frequency of the ambient vibration is below 4 Hz, and the dominant frequency of the train-induced vibration is between 8 and 16 Hz. (2) The first, second, and third order natural frequencies are 1, 3.25, and 6 Hz, respectively, in the west-east direction, and are 1, 3.25, and 6.25 Hz, respectively, in the north-south direction. (3) The two weakest locations (A and B) of the Probhutaratna pagoda are observed at the spire bottom and west gate of the first floor. At location A, the maximum principal stress reached 243.6 N/m2 and the corresponding maximum tensile strain reached 3.74×10−7.
... The method of establishing dynamic analysis model of ancient building was put forward by combining experiment and theoretical analysis based on the simplified variable cross-section cantilever model with bottom fixed. Moreover, Yuan J.L. et al. [5][6][7][8] analyzed the dynamic characteristics of Suzhou Huqiu Pagoda and Zhongjiang South Pagoda by the field nondestructive environment-excited vibrating test, the classical theory analysis and computational simulation. The modeling method of dynamic characteristics was suggested. ...
To study the dynamic characteristics and seismic performance of the Shengshousi Pagoda, the present status preserved of the pagoda’s structure was investigated on site, and the numerical computation model was established based on the parameters determined by calculated value of the natural vibration frequency of the structure. The responses of acceleration, displacement, story drift and stress were analyzed under three-way seismic wave. The seismic performance of pagoda structure was evaluated according to the calculation results of displacement and stress, and the failure criterion of pagoda materials. The results indicate that the natural frequencies in the east-west are close to that in north-south. The response laws of acceleration, displacement and stress are similar under three-way seismic wave of 8-degree fortification earthquake. Under the frequent earthquakes, the structure of pagoda does not suffer from compression damage; the tensile damage area is located at the bottom floor. Under the fortification and rare earthquakes, significant compression damage area is located at lower floors of the ancient pagoda, the stress concentration occurs around the part of opening, and significant tensile damage occurs.
... Researchers have conducted many studies to analyze the vibrations of historic buildings . The dynamic characteristics of structures have been measured using field tests based on the ambient vibration exactions [1,2,5]; the identified modal parameters were then used to update the finite element (FE) model of the target structure [8,[13][14][15]21], which was in turn used to develop the prediction methods. Breccolotti et al. [10] established a methodology for predicting the vibration levels induced by railway traffic. ...
... Based on the above constraints, the traditional methods for the modal parameters identification of structure in the time domain or in the frequency domain are not applicable for this test. Yuan et al. [21] proposed a new method for identifying the modal parameters by comprehensively analyzing the autocorrelation function, frequency response function, transfer function, and cross-correlation function of the vibration signals. The frequency response function ( ) is defined as ...
... where Φ is the coefficient of the vibration mode, ( ) is the transfer function, ( ) is the auto-PSD function, and ( ) is the cross-PSD function. The sign of Φ is determined by the phase relationships of the cross-PSD between different measurement points: the sign is positive for the same phase and it is negative for different phase [21]. ...
A prediction method in the frequency domain is proposed for predicting the vibrations of historical timber building induced by traffic loads. The modal parameters of a structure are identified using a double-confirmation analysis method based on the autospectrum. Then, the vibration responses of the building are calculated using a limited number of measurement records by inputting the calculated vibration information for the foundation of the updated building model. The proposed method is used to predict the vibrations of the Buddhist sutra depositary at Yangzhou Zhunti Temple. Comparing the results shows that the vibration responses of a structure under traffic loads can be effectively predicted in the relevant frequency bands.
... This makes it difficult to identify the structural modal parameters using the time domain and traditional frequency domain methods. The literature 33 provides a new method in which the modal parameters can be identified by comprehensively analyzing the auto-correlation and frequency response functions of vibration signals of the test points, and the transfer and cross-correlation functions between different test points vibration signals. ...
A prediction model of the structural vibration responses induced by the running trains is established. The modal parameters of the structure are identified using a double-confirmation analysis method based on the auto-spectrum, and the vibration responses of the building are calculated from a limited number of measuring records by inputting the measured vibration information to the foundation of the updated building model. The proposed method is validated by an in-situ experiment of a five-floor residential building near a railway. It was found that the calculated vibration level corresponds well with the measured ones in the concerned frequency bands.
The dynamic properties and anti-earthquake behaviors of Pagoda in Songyue Temple was studied by numerical simulation method. Firstly, based on the its contexture, the equivalent model reflecting the force transfer mechanism is established. Secondly, by analyzing the dynamic characteristics of the computational model, the vibration modes, natural vibration frequency and natural period of vibration are measured. The correctness of the model verified by comparing the theoretical calculation results and the simulation results. Lastly, the seismic behaviors of the Pagoda in Songyue Temple was evaluated according to the elastic spectrum analysis and time-history analysis results and related data. The results show that: the stiffness is uniformly distributed and the seismic performance is good enough. Under the action of earthquake force, it is easy to produce tension rupture and the tacha, the pagoda body without section change, as weak link of the structure, need to focus on.
Equipment has a significant influence on the dynamic behavior of the structure in the direct air cooled condenser support platform. The dynamic properties of four direct air cooled condenser support platforms are measured in site, and identification of the structural dynamic characteristic parameters under the excitation of fans is researched. A 1/8 scale model is constructed and tested. The structural dynamic properties, the resonance vibration frequency of the structure and fans, the amplitude-frequency curve under different work states of fans, and the dynamic strain of typical members are measured in the experiment. The modal analysis and steady state analysis are also performed, and the calculation results show agreement with the test results. The results can be used to comprehensively understand the interaction between a piece of equipment and a structure as well as the structural vibration properties of the direct air cooled condenser support platform.
In order to measure dynamic characteristics of a single-layer reticulated dome model during shaking table test, firstly the acquisition of noise was performed to eliminate various environment noises with bigger interferences in shaking table test. Then, the dynamic responses of the model under the actions of white noise and the fast sine sweeping with different amplitudes were used to datermine the response amplitude to be measured for the test and the dynamic characteristics of the model. In addition, the hammering method was also used to measure the dynamic characteristics of the model, its results were analyzed using the random decrement technique combined with HHT method. It was shown from the test results that the modal frequencies of a single-layer reticulated dome are intensive and the environment noise interference must be eliminated for their large effect on the test results; the results of the dynamic characteristics of the model are almost identical using the above mentioned three methods. Finite element simulation for the dynamic characteristics of the model with ABAQUS was completed. Comparing results showed that the numerical results are in good agreement with the test results, so the dynamic characteristics of the model can be accurately simulated using ABAQUS based on an accurate FE model. All the results provided a foundation for the further shaking table test and aseismic performance study of reticulated shells.
The dynamic behavior is an important index to evaluate the seismic property and structure damage of historic pagoda. On the base of the research of protection technology on Jinaozhou pagoda, the key points and schemes for applied ambient random excitation technology to determine the dynamic behavior of ancient masonry pagodas is introduced. Test results obtained are ideal, and obtain some datas that are beneficial to Jinaozhou pagoda preservation through comparison of test results during four years. It is believed that the present research can provide a valuable reference for the eternal protection, reasonable development and utility & Long-term health monitoring of similar ancient pagodas.
