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For different structural system of cable-stayed bridge, the dynamic characteristics have obvious difference under seismic load. Dynamic time-history analysis of earthquake was applied, and the EI Centero seismic wave with modified peak acceleration was chose as the earthquake acceleration time-history input. As Jiangsu Siyang special-shaped single tower cable-stayed bridge for engineering background, considering geometric nonlinear of structure, the differences of dynamic characteristics of cable-stayed bridge structures were gained under two different situations. The single longitudinal seismic ground motion was chose under the first situation, while the longitudinal, lateral, and vertical seismic ground motion are introduced. For floating system, the displacements are the largest and the inner forces are the smallest. For rigid frame system, the displacements are the smallest and the inner forces are the largest. The others are not much difference. Comprehensively, semi-floating system has better performance under seismic load.

The spatial distribution function assigns seismicity parameters of seismic zone and belt to the potential earthquake source area seismic by the magnitude interval, determination of the spatial distribution function is one of the key technologies to comprehensive probabilistic seismic hazard analysis methods, and the results will directly influence seismic hazard analysis results of the calculated sites. However, the spatial distribution functions are hard to get by statistics due to serious lack of seismic samples, and evaluation factors used in the actual work are too complex and not independent, the spatial distribution function is lack of reliability. In this paper, Bohai seismic tectonic area is chosen as an example; geological data are obtained from the newly built offshore oil platform engineering in recent decades, while seismic activity data are obtained by checking from historical difficult seismic parameters. Five factors are adopted in this area, including potential seismic focus area, seismic tectonic, seismic activity level, long-term forecasts, and strong earthquake recurrence interval and construct empty segment. Spatial distribution function of Bohai Sea earthquake structure area is obtained by weighted comprehension; it reflects the spatial and temporal heterogeneity of seismic activities in the area, and provides the calculation parameters for the probabilistic seismic hazard analysis.

To explore the practical rail-bridge seismic design methods, dynamic response analysis model of the train-rail-bridge system under seismic loads was established, and the widely used simply supported track-bridge in rail transport was taken for the study. By inputting different intensity and frequency artificial seismic waves to the train-rail-bridge system, the whole history of the vehicles running through the bridge is simulated and the dynamic responses of the bridge and the vehicles are calculated. The influence of train type, seismic intensity and spectral characteristics of the earthquake were analyzed. Taking Japanese traffic safety evaluation indexes including derailment coefficient, wheel offload rate and lateral wheel-rail force as evaluation criteria, the allowed lateral bridge displacement limits and acceleration limits that ensuring train running safety under earthquake were obtained, and the bridge vibration limit curve was drawn. Using Lagrange interpolation method, the mathematical expression of the curve was worked out, which can provide a reference to rail-bridge aseismic design.

This paper is a seismic response study on a vertical irregular frame structure which has a cantilevered top floor. Aimed to analyze the features of seismic response for a vertical irregular frame and scaled model, dynamic time history analysis and shaking table test have been carried out by use of the earthquake waves recorded in WENHUAN earthquake. It shows that the results of dynamic time history analysis and shaking table test are in good agreement, and the earthquake influence coefficients obtained by dynamic time history analysis and shaking table test are larger than the value according to Code, which indicates that the results would be not secure if the simplified methods specified in Code only in the sight of the calculation of earthquake loads.

In this paper, the new Fengman gravity dam is numerically simulated to study the seismic response and safety evaluation by considering the different strength grade concrete partition, corridor, a discharge hole and gate pier. A complex 3D FEM of a real overflow monolith was built by taking advantage of AutoCADand ANSYS, nonlinear seismic response was studied under earthquake loads. Numerical simulations show that acceleration, displacement and stresses of dam were obtained in a complex 3D FEM under seismic precautionary intensity of 7 degree earthquake loads, results compared with the dam simple models were on the safe side. Fengman dam was still safe under seismic precautionary intensity of 8 degree earthquake loads, so the dam had enough capacity to resist earthquake action. At the same time, it is concluded that 3D dynamic FEM is very important for safety evaluation of concrete gravity dam subjected to the earthquake. The research provides finite element analysis reference works for comprehensive governance and reconstruction of Fengman Hydropower Station.

To evaluate the earthquake resistant behavior of the nuclear island buildings of new generation PWR, in this study we formed the three dimensional finite element model of nuclear island structures ,which incluse shield building, the auxiliary building, the containment vessel, and the containment internal structures. Modal analysis was performed to to reveal the structural dynamic characteristics.And with the auumption of hard bedrock support media ,the dynamic response nanalysis of the nuclear structures under earthquake was conducted,respectively with response spectrum method and time history method.It shows that the seimic response of the strucures conform with the design level.Under the input excitations of SSE(safe shutdown earthquake) level, the iner forces and deforamtions can be well controlled in linear elasticity.

Collapse and landslide induced by"5.12" Wenchuan Earthquake generated a large number of loose solid material, which still remained on the mountain. Aftershocks and heavy rain conditions will induce secondary geological disasters, a direct threat to human life and property security and reconstruction results. Based on the landslide of Hanyuan Two Pretty mountain, this paper studied the basic characteristics of landslide before and after earthquake. The finite difference method is adopted to simulate landslide process, and the stress-strain law and failure trend is explored in three conditions including the natural, rainfall and seismic condition. After this, the method of strength reduction is used to analyze slope safety factor in different rainfall conditions. The analytical results are consistent with the macrogeological phenomena before and after earthquake. Research results can provide a reliable basis for the future study of the impact of earthquakes on the landslide and disaster prevention and mitigation.

Brick-wood building is one kind of widespread rural houses in villages and town of China, which has potential hazards to people lives and properties during strong earthquake, so that it is necessary to investigate its earthquake damage behaviors. Based on a great many of earthquake damage examples from historical earthquakes, characteristics and mechanics of earthquake damage of brick-wood building were analyzed and summarized. Earthquake damage modes for brick-wood building are mostly horizontal shearing damage, which tends to occur at positions with weak strength in horizontal direction or weak connections between different structures such as walls between doors and windows, intersections between lengthwise and cross walls, bottom of gable, and connections of beam with sommer beams, et al. Brick-wood building generally has better anti-seismic behaviors in earthquake intensity of VII, while worse behaviors in earthquake intensities of VIII, IX and X. Even though, if reasonable anti-seismic techniques and reinforced measures are applied to brick-wood house, it will have better anti-seismic behaviors.

Earthquake prediction is a difficult global scientific problem. As one aspect of the earthquake prediction, seismicity prediction and subsequent earthquake is also a big difficult of science problems. Analysis of the seismic sequence and the study of the main parameters (magnitude, radiation energy, apparent stress, seismic moment) and subsequent aftershocks is an important basis for prediction of seismicity and subsequent strong earthquakes. In this study, the relations between some of main shock parameters and the maximum aftershock are obtained based on association rules.

The paper is utilizes the double difference method of to relocate the north and south earthquake belt's Ludian earthquake sequence to obtained the Ludian earthquake sequence's detailed earthquake parameters. And at the same time we have established an whole set of perfect method in data processing and result analysising. Have the ability of useing'the north and south earthquake belt earthquake to strengthen the monitor's real time data to accuratly relocate the medium intensity earthquake sequenc of the north and south belt. Thus,we could produce the more accurate earthquake parameter, and short provides a more conclusive evidence into the warning area division and earthquake forecast.

It is indicated by many earthquake damage surveys that the seismic design of underground structures is a key issue for underground caverns. However, methods regarding seismic design of underground caverns have not been covered by current national codes. The wave field stress method is a kind of method in which the additional stress induced by earthquake is calculated based on the dynamic features of structures. Based on the earthquake damage survey of the underground cavern at Yingxiuwan hydropower plant after Wenchuan earthquake, the wave field method is used to analyze the structural response under earthquake impact. After comparing calcluation results to field findings, it is discovered that they are basically in good agreement. Therefore, it is concluded that the wave filed stress method can be adopted to assist the seismic design of underground structures during the preliminary design phase of project.

A novel imminent earthquake analysis method is proposed. Firstly, BHZ data are acquired from seismic networks, then, structure parameters of part of the earth are identified based on SSI (stochastic subspace identification); finally, imminent earthquake is analyzed based on the results of system identification. It is prevented from entering earth interior or using artificial seismic explosion. Location of epicenter and process of earthquake on imminent earthquake can be analyzed based on characteristics of main vibration frequency, change trend of model shape and damping by using SSI to analyze field data on earthquake event.

The paper studied the dynamic second order effects response of the single-degree-of-freedom (SDOF) system under vertical earthquake ground motions. The following achievements have been made: (1) the motion equations under vertical earthquake loading with second-order effects were established; (2) through numerical analysis, the regular patterns of structural dynamic second-order effects subjected to vertical earthquake loading are uncertain.

In this study, we chose East China offshore areas as study region(N25°~41°，E117°~126°).According to the tectonic environments and characteristics of earthquake the seismotectonic units were established, taking Gaussian spatially smoothing only based on the input earthquake catalog, and fault-rupture-oriented elliptical smoothing to calculate the seismic activity rate in each cells. The maps for the distribution of horizontal peak ground acceleration with 10% probability of exceedance in 50 years were obtained through using the method of seismic hazard analysis based on cell source. While the total number of earthquakes unchanged, two-stage smoothing procedure deals with the error of epicenter location, contains the seismotectonic information in elliptical smoothing seismicity model. This method build up a simple and easy methodology of probabilistic seismic hazard analysis, especially for those place where not yet been clearly master the seismic tectonic information and with distributed Seismic activity.

Base on the large-shaking table model test，studies on the seismic response characters of shallow tunnel in different earthquake intensity are made by mainly using numerical simulation. The results indicate that there is a good agreement between the model test and numerical simulation. the different earthquake intensity has great effects on the seismic response characters, The distribution of the lining cross-section’s internal force is oval-shaped and the value which in conjugate 45° direction is greater than crown and bottom of arch. Moreover, the internal forces vary from earthquake intensity in the same direction. It is great to recognize the seismic response characters of shallow tunnels through the study results and it provides reference for the similar projects.

The pattern and characteristics of seismic damage for Shuangjiangkou ECRD and Houziyan CFRD models were studied through large-scale earthquake simulation shaking table tests in this work. The test results showed that the main earthquake damage pattern of rock-fill dam is permanent residual deformation and shallow slide on the downstream slope. Seismic residual deformation of rock-fill dam, which is filled and compacted well, is very small. Regardless of ECRD or CFRD, the horizontal displacement and settlement on downstream slope are significantly larger than upstream slope under empty reservoir. The analysis of residual deformation and vibration frequency before and after failure indicated that aseismic performance of CFRD is superior to ECRD. Because of the remarkable whipping effect in the high rock-fill dam, the key parts of aseismic design is downstream slope near the dam top, where appropriate aseismic measures should be taken.

Combining with performance grades of reinforced concrete structures at home and abroad, the seismic performance of masonry-infilled frame structures can be induced into five levels: basically normal, slight damage, medium damage, severe damage and collapse prevention. The limit states of all seismic performance levels and their dominating parameters of masonry-infilled frame structures are put forward, and quantified performance index of this structure are obtained on the basis of statistical test data. The seismic response of pure and masonry-infilled frame structures are compared by using capacity spectrum method and equivalent strut model, and the result indicates that the structure could meet predetermined performance objective under the minor and major earthquake levels by comparing the practical story drift and proposed performance index.

So the consistent seismic wave model and multi-point seismic wave model are established based on the solid-fluid interaction theory in this paper. According to the analysis of the seismic response, the results show that: the effect on the dynamic response of the aqueduct in the soft site is greater when the seismic wave velocity is small. Therefore, in the seismic study of long-span structures, when the wave velocity is smaller, it is critical to consider the effect of the earthquake's multi-point input, so that the results can be coincident with the actual situation.

A networked structural laboratories system for evaluating the seismic performance of large-scale structure systems by seamlessly integrating geographically distributed experimental and computational substructures into a single test is described in this paper. It consists of an independent network based communication platform and various applications. The effectiveness of the proposed system is demonstrated by remote hybrid tests of a six-span bridge system at the Hunan University, Harbin Institute of Technology, Tsinghua University, China and the University of Southern California, USA. Successful application shows the system enables the shared use of testing resources by integrating single structural laboratories into a powerful and networked laboratory with advanced capability.

Augmenting the flexural strength of columns in the seismic design of reinforced concrete (RC) moment resisting frames is a key measure among all the detailing procedures of seismic capacity design, which induces the desirable beam side-sway mechanism for the structure to dissipate energy during a strong earthquake. The objective of this paper is to assess the influence of various strong column factors which is employed to perform seismic vulnerability analysis to the seismic performance of a six-story deterministic RC frame structure. Seismic vulnerability analyses indicate that augmenting the flexural strength of columns is an effective measure to improve seismic performance of RC frame structures. Increasing strong column factor improves the displacement capacity of structure and induces the biggish grads between the different damage limit states, which provide caution to prevent the abrupt collapse of structure during a strong earthquake. Seismic vulnerability curves provide the quantitative criterion for evaluating the seismic performance of structure and choosing appropriate target strong column factor.

In this paper, the elasto-plastic dynamic analysis on dynamic failure behaviors of steel double-layer grids supported by tridimensional truss columns used in a gymnasium with the function of earthquake victims shelter under disaster earthquake is carried out under EL-centro wave with SAP2000, and the appraisal results on their anti-failure performances are presented under strong earthquake action based on the plastic-hinge theory. In the analyses, the geometric and material nonlinear effects are considered simultaneously based on the plastic-hinge theory. The plastic development level of the rod, the deformed shape and the failure type and the ductility are estimated by plastic hinge principle. The results show that the failure model of the structure under the earthquake wave action is the complicated combination of strength failure and elasto-plastic dynamic local buckling in deferent areas of the structure; When the structure reached its failure critical limit, the development of the plastic hinges is not sufficient and only 9.99% of the rods enter into their plastic stage; The ratio of its maximal failure node vertical displacement and its short span is 1/331, which can meet the need for flexible non-structural attachment; The ratio of its maximal failure node horizontal displacement and its columns is 1/166; Its critical failure peak acceleration of EL earthquake wave when applied in the combination of three directions is 602gal, which is 1.5 times more than the official seismic fortification level of 8 degree (major earthquake, 0.2g) and can be served as earthquake victims shelter in the area of 8 degree seismic fortification; Its displacement ductility coefficient is 5.65,which shows the structure owns good energy dissipation capacity.

Occurrence of frequency of earthquakes around the world has been increased including Sendai earthquake in Japan and magnitude of earthquake has also increased. Recently, many tall buildings using local seismic codes can be exposed to the risk of an earthquake and wind. Also, some buildings, which was planned to be built, were foundered as a result of lack of finance. Therefore, for tall buildings, structural safety such as earthquake and wind resistant performance, and financing issue are very important to progress the huge project. So we need to find another optimum alternative other than damping devices and base isolation system. In this study, four types of test specimens are used, which are fifty-story base tall building, tall building that was reinforced with diagonal brace, x-brace, and Chevron brace. And all of these cases, are subjected to the seismic load and wind load, finally analyzed and compared for seismic and wind performances.

The paper rests on the basic principle of the double difference method, through using Kennett and Engdahl(1991)’s IASPEI Earth model which can be used in computation theoretical travel time in the condition of regional and telseismic earthquake .We have developed a double difference program which can be used in the regional and teleseismic earthquake. And utilizes this program to relocate the Jiashi Ms 6.8 earthquake sequence in Xinjiang province on 24/2/2,003, obtained a quite good result.

Analyzed the importance of selecting reasonably ground motion input in seismic fragility analysis of the bridge. Based on the common methods of synthesis artificial seismic wave which used trigonometric series and according to the characters of Fourier series, extracted phase spectrum from practical seismic waves ,through modulating the Fourier amplitude spectrum, obtained the artificial seismic wave which fitted compatible with the design response spectrum. Similar to nature small earthquake records, it has the character of non-stationary on time-domain and frequency-domain. Synthesize a series of artificial seismic waves in this method, can improve the accuracy and pertinence of the bridge seismic fragility.

In order to establish the systematic design method of performance-based earthquake engineering for steel-concrete hybrid structure tall buildings, a 1/15 scale model shaking table test is conducted in State Key Laboratory for Disaster Reduction in Civil Engineering of Tongji University. The dynamic property, acceleration and displacement response of the model structure under different earthquake levels are investigated from the test. The failure mode of structure is analyzed and the seismic response of the prototype structure is interpreted according to the similitude relation. The conclusions drawn from this investigation show that the prototype structure can basically satisfy the requirements of no damage under frequent earthquakes and no collapse under rare earthquakes; steel frame- concrete core structural system has good seismic performance under rare earthquake; and the damage of the connection between the steel frame beam and the core wall is the main failure pattern of the structure.

Considering back and forth and the complexity of earthquake loading, according to theoretical analysis, this paper is verified theoretically that the natural frequency changes of structure contain the information such as location and degree of the damage in earthquake, based on this theory, applying the large common software – ANSYS, and an experiment to simulate the damage of a six-storey-high frame structure is used, extracting the natural frequency changes and forming the input vectors of the neural network, the structural damage is detected by the neural network trained, the result showed the effectiveness of this method in the engineering.

A large number of earthquake disasters indicate that the underground structure, such as metro tunnel, is not safe and reliable as people think, and can also be destroyed and collapsed under dynamic load, e.g. earthquake. Therefore, it is necessary to study the seismic response analysis of underground structure in great detail for underground structure under dynamic loading, especially under the earthquake load. Hence, in view of the soft soil of Hangzhou, the 3D non-linear finite element software ADINA is used to study the seismic response of section tunnel of Hangzhou metro line 1, to summarize the earthquake response characteristics of the subway underground structure, and to provide the calculation results of metro tunnel’s seismic response and the change rule of lining deformation and stress. The conclusions obtained can provide some reference values in the seismic design of metro tunnel in soft soil regions.

Considering the uncertainties in structural capacities and seismic motions, a probabilistic-based seismic risk analysis approach for bridges is proposed in this paper. In this approach, the Total Probability Theory (TPT) is used to divide seismic risk analysis into three main steps: seismic hazard analysis; structure damage analysis; and failure probability analysis. The parameters of seismic risk analysis are assumed to be an independent and discrete Markov process, resulting in rigorous and consistent seismic risk functions for calculating the annual average probability of exceeding a designated limit state of structure under a specific level of seismic intensity. A case study of seismic risk analysis was performed on a three-span continuous rigid-frame bridge. The results show that the approach presented in the paper is applicable for the seismic risk analysis of bridge structures, and is an effective tool to assess the performance of bridge structures under earthquake actions.

This paper is concerned with investigation of the dynamic behaviors of cranes under seismic effects. For this purpose, firstly we have performed experiment on a 1/20 scale crane model on the shake table with real earthquake data, then a multi degree-of-freedom non-linear mathematical model is developed including behavior of the container cranes under earthquakes and simulated. The simulation system has a five degrees-of-freedom and modeled system was simulated for the ground motion of the El Centro earthquake in USA, 1940. Finally, the time history of the crane bridge displacement and acceleration responses of the both theoretical and experimental cases are presented. Theoretical and experimental results exhibit that the mathematical model is accurate. This study also shows the destructive effects of high accelerations which occur during the earthquake. These effects cannot be omitted in the design of cranes. The result of this study which is an accurate mathematical model can be inspiring for the engineers in terms of design parameters.

This paper carried out the seismic performance evaluation of a super-tall hybrid structure. The hybrid structure consists of steel reinforced concrete (SRC) frame and reinforced concrete (RC) core wall. Based on the characteristics of the structure, the structural system, seismic performance objectives and seismic measures are presented. Moreover, the elastic response spectrum analysis, elastic and elasto-plastic dynamic analysis are performed to evaluate the seismic behavior of the structure at different seismic hazard levels. The conclusion can be drawn that through the seismic measures taken in the paper, the super-tall structure could generally achieve the seismic performance objectives.

There are a large number of acceleration records obtained in the near fault strong motion of Wenchuan earthquake in 2008, which greatly enriched the database of strong motion. This article compares seismic records of Wenchuan earthquake with other domestic and international earthquakes, such as response spectrum, multi-peaks average and R. It also discussed a damage reason of fault zones in Wenchuan earthquake.

The acceleration record of an earthquake ground motion is a nonstationary process with both amplitude and frequency content varying in time. The paper presents a general procedure for the analysis and simulation of strong earthquake ground motions based on parametric ARMA models. Structural design spectra are based on smoothed linear response spectra obtained from different events scaled by their peak values. Such an approach does not incorporate other characteristics of the excitation represented by measured data. This study investigate the use of non-stationary models which can be considered characteristic and representative of specific historical earthquakes. An earthquake record is regarded as a sample realization from a population of such samples, which could have been generated by the stochastic process characterized by an Autoregressive Moving Average (ARMA) model. This model is capable of reproducing the nonstationary amplitude as well as the frequency content of the earthquake ground accelerations. The moving time-window technique is applied to synthesize the near field earthquakes, Boumerdes-1, Boumerdes -2, and Boumerdes -3 2003 recorded on dense soils in Algeria. This model, is based on a low-order, time-invariant ARMA process excited by Gaussian white noise and amplitude modulated using a simple envelope function to account for the non-stationary characteristics. This simple model gives a reasonable fit to the observed ground motion. It is shown that the selected ARMA (2,1) model and the algorithm used for generating the accelerograms are able to preserve the features of the real earthquake records with different frequency content. In this evaluation, the linear and non linear responses of a given soil layer have been adopted. This study suggests the ability to characterize the earthquake by a minimum number of parameters.

Performance objectives and contents of resistance verification for high speed railway bridge are embodied and quantified based on the theory of performance-based seismic design. The resistance verification is proposed, which can control the damage under design earthquake and ensure safety of the pier under low-level earthquake. The simplified capacity spectra method for calculating displacement ductility factor is proposed by using strength reduction factor. The method for evaluating damage of RC bridge pier in high-level earthquake is presented by using maximum displacement and hysteretic energy. The proposed approach and procedures for performance-based seismic design are easily to implement. The performance-based seismic design procedure is demonstrated by using an example.

Seismic performances of high-rise buildings are urgent to be studied given the background of the 2011 off the Pacific coast of Tohoku earthquake and probable long-period ground motions happened in subduction zone near east-coast of Japan. One 20 story frame of CFT and steel high-rise buildings were modeling, and seismic responses of models were simulated in FEM program with fiber model subjected to extreme ground motions recorded in the 2011 off the Pacific coast of Tohoku earthquake and the relevant artificial ground motions. Analysis results indicate that, the frame models could not satisfy the seismic demand under extreme ground motions. The CFT model has superior ultimate stability behavior than steel model as result of confinement effect of confined concrete to steel tubular. The phenomenon of deformation concentration along with vertical direction becomes more intense when the inputting acceleration level arrives extremely higher.

Take the roof of the palace timber structure as the study objection, according to the requirements of the Ying-tsao fa-shih, it establishes the model. Through the analysis of the dynamic properties with ANSYS finite element software and shaking table test, it gets the structural dynamic properties and its maximal response under different conditions, and abstains the seismic amplification coefficient of the beams layer and the whole structure, compares the results reached by shaking table test with the numerical simulation. Research shows that the nature frequency of the model is 1.486 Hz; the roof’s nature frequency is much bigger than that of the whole structure; with the increase of earthquake and the height of model, the maximal displacement value of beam layer gradually increases; the shock absorption effect of semi-rigid Sun-Mao connection in major earthquake (400gal) is better than that in moderate earthquake (220gal)and minor earthquake (110gal); the seismic amplification coefficient value between layers lies in 1, that between roof and arch shop lies in 0.9 or so.

Based on the damage field survey of the industrial building in Wenchuan earthquake, the typical building seismic damage characteristics of industrial structures were summarized and analyzed. According to the damage phenomenon, the following conclusions are derived: usually, the main structures of industrial buildings received serious damage, which roof system were distorted and collapse, bent-frame column were pressed and yielded, bracing system were tension broken or pressed and yielded; when the main structures of industrial building received minor damage, the non-structural member regular suffered relatively damage, include the end bays in the longitudinal direction, high gables, the cantilevered walls between two span with different height and the foundation. Then damage rules and reasons are summed up and damage characteristics and the corresponding design and retrofitting suggestion are proposed. At the end of the paper, it was indicated that seismic design of major structure and non-structural members of factory building must be fully complied with the Seismic Design Code, seismic assessment and seismic strengthening should be carried out at regular intervals for the existed industrial building, which served a long time and whose fortification level is unsatisfied with requirement.

Seismic response of a high-rise building under rare earthquake is numerically investigated in the paper. The Height of the building is 266m, which goes beyond the limit of 150m in Chinese standard, so nonlinear analysis should be performed to investigate its elasto-plastic behaviors under severe earthquake excitations. In the finite-element model for analysis, beam-column members of the structure are simulated by beam elements, while the core tube is simulated by shell elements. The concrete damage plasticity model is used for concrete members, while the kinematic hardening rule is defined for steel beam-column members. Four sets of earthquake wave, including 3 sets of strong earthquake records and 1 set of artificial wave, are adopted in the analysis. The analysis results show that, under severe earthquakes, steel frame members and steel truss members in the strengthened floors keep elastic. Severe damages are detected in almost all coupling beams in the core tube, as well as shear-walls near strengthened stories, where lateral stiffness would decrease seriously. Through the investigation, it is also found that the largest story drift is less than the maximum allowable value in the Chinese code for seismic design of buildings. So it is concluded that the high-rise building will not collapse when the place is subjected to severe earthquakes. Besides, some design suggestions are proposed according to nonlinear dynamic analysis in the paper.

With the thin-wall dynamic analytical model of aqueduct for fluid-structure coupling, the seismic reliability of aqueduct is studied. In this model the influence of the bend-torsion coupling, water-structure coupling and nonlinear rubber bearing isolation are all taken into consideration. Based on the type of site soil, the artificial seismic waves are created. In accordance with the maximum entropy principle and the measured data of structural internal force under earthquake, the reliability distribution function and the aqueduct reliability are calculated.

In the paper, the seismic damage information of six kinds of buildings, including Brick and concrete structure, the bottom frame brick and concrete structure, frame construction, Big span structure, special structure, farmhouse, were collected. Based on the architecture type, damage degree, height of house, the seismic damage information were statistic analysis in the damage characteristic of the structure. And on the basis of the damage characteristic, the dynamic response and earthquake resistance mechanism were studied. The correlation among site feature, structure type, strength of materials, construction technology and the seismic damage of structure were discussed.

Traveltime calculation has been applied in many project extensively such as earthquake simulation, prestack migration, tomographic imaging, velocity analysis. finite-difference solution of the eikonal equation along expanding wavefronts had two prominent characteristics:one was wavefront points update very frequent, Usually insert some new wavefronts points after extacting one minimum point every time;the other was that the new calculated wavefronts’s traveltime was usually large.Therefore,the paper introduced binomial heap sorts method, optimizated the method of inserting new wavefronts and removing the minimum point in wavefronts, ensured the search efficiency, and had good time complexity.

In order to discuss the effect of earthquake and dynamic ice loads to a bridge pier, this paper considered the effect of added mass of dynamic water, and it deduced the dynamic equilibrium equations for a bridge pier subject to earthquake and dynamic ice loads on the basis of nonlinear Morision equation. Using numerical analysis method, it discussed the dynamic response of a bridge pier subject to different types of earthquake loads, forced ice loads, and both earthquake and forced ice loads. Through comparing the pier responses in different work conditions, it discovered that the dynamic responses of the bridge pier subject to forced dynamic ice loads rise and fall severely at the time of ice buckling broken periodic change. The coupling effects of forced dynamic ice loads and earthquake especially near-fault earthquake enhance the dynamic response of bridge pier significantly.

Earthquake ground motions were reasonally selected for the nonlinear dynamic time-history analysis conducted for a two-tower long-span cable-stayed bridge. The correlation between frequency content of earthquake ground motions and probabilistic seismic demands reveals that the geometric mean and dispersion of response spectra from earthquake ground motions have significant effects on probabilistic seismic demand assessment of long-span bridge stuctures and these effects are related to the difference of the shape of geometric mean spectra in the important period ranges where cumulative modal mass participation is significant. Response spectra of selected earthquake ground motions should match well with target spectra in the important period ranges. If input ground motions are reasonally selected, analytic results can be obtained more precisely and effectively and more amplitude parameters can be selected as intensity measures.

The solution method for earthquake responses of non-proportion damping system based on Clough-Penzien three-step non-stationary seismic random model is investigated in this paper. Firstly, the unified motion equation of non-proportion damping system is set up and then decoupled by complex mode method. Secondly, the earthquake responses in time-frequency domain are calculated by taking Clough-Penzien three-step non-stationary seismic random model as excitation, which ground motion parameters consistent with that of design response spectrum in china seismic code, and then the non-stationary time-varying variance of earthquake responses can be obtained, subsequently, the variances of equivalent stationary responses are integraled in ground motion duration. At last, an example of base seismic-isolation system is given to show the application of the proposed method.

The objective of the paper is to present a method for structural damage presence detection from the time-varying modal parameters identified from the seismic response records in great earthquake. The time-domain system identification method RARX (Recursive Auto-Regression with exogenous variables) model is adopted to identify the time-varying parameters including modal frequencies and damping ratios from the seismic response data. Then the damage presence is detected from the change of parameters during earthquake. A 7-story reinforced concrete building, which had suffered moderate damage and recorded seismic response in Chi-Chi Earthquake, is used for the analysis. It is found that the damage presence can be determined from the decrease of the modal frequencies or the increase of damping ratios, and the time at which the building is damaged can also be detected from the time-varying modal frequencies. The results can be considered as the supplement materials for structural safety evaluation, structural damage investigation and related works.

Earthquake is one of the main geological disasters that cause slope instability. The stability analysis of soil-rock mixture slope under earthquake is made with FLAC3D in this paper. According to finding the shear strain concentrated deformation zone and the size of the displacement, they can help us to find the possible instability of the scope and location. The study result shows that the slope is stable in the natural state and certain displacement would occur in the potential slide mass of the slope under earthquake, and this must be taken into serious consideration in practical engineering.

Selected the typical loess landslide to analyze and calculate, adoption of elastic-plastic dynamic FEM and Drucker-Prager yield criterion, using Earthquake motion time-histories as the seismic input will be based on the fitting of , class standard response spectrum curve in the current seismic resistance design code. From the analysis of loess slope deformation and breach at different peak acceleration, spectral and duration, it shows the dynamic response and change rule of soil under earthquake effect.

It is well-known that seismic disaster will cause serious damage, so the prediction and evaluation of seismic loss before earthquake event happened can provide foundation of disaster reduction program. And after seismic event happened, it is very important to fast evaluate the seismic disaster loss. Traditional seismic loss prediction method is vulnerability list method which need detailed information about all kinds of structures and facilities of the evaluated areas, and for most areas, it is very difficult to get such detailed information. This paper brings forward a new simple fast prediction method for seismic economic loss. Firstly, a macroscopic vulnerability model was discussed. secondly, a three-layer BP network model for seismic economic loss prediction is built up, BP network model is one of the most widely used artificial neural network (ANN) model, but due to its deficiencies such as easy to get into local extreme minimum value, genetic algorithm (GA) is introduced to overcome the deficiencies. In this model, seismic intensity, average GDP per capita and per area, population density are selected to be the input layer index, and GDP loss ratio as the output layer, 80 earthquake events which happened recent years are regarded as training and check up samples. Finally, the economic loss caused by Wenchuan earthquake is evaluated by the proposed model, and the feasibility and practicability are validated by the numerical example.

Cold-formed steel structure is suitable for post-earthquake reconstruction since its good seismic performance and construction speed. Analyzing the dynamic characteristic of a two story office building by using the finite element software ANSYS. And the results show that: (1) in the time history analysis based on three types of seismic waves the lateral displacement of the structure and rotation between layers to meet the relevant specifications when confront the rare earthquake (2) Under the seismic loads, earthquake response acceleration amplification factor is smaller which indicating better seismic performance and it can be used in areas with high seismic intensity.

This paper presents the performance of base-isolated steel structures under the seismic load. The main goals of this study are to evaluate the effectiveness of base isolation systems for steel structures against earthquake loads; to verify the modal analysis of steel frame compared with the hand calculation results; and development of a simulating method for base-isolated structure’s responses. Two models were considered in this study, one a steel structure with base-isolated and the other without base-isolated system. The nonlinear time-history analysis of both structures under El Centro 1940 seismic ground motion was used based on finite element method through SAP2000. The mentioned frames were analyzed by Eigenvalue method for linear analysis and Ritz-vector method for nonlinear analysis. Simulation results were presented as time-acceleration graphs for each story, period and frequency of both structures for the first three modes.

Evaluation on dynamic energy characteristics of building under earthquake excitation with passive friction damper-protected devices based on finite element method (FEM) is actively carried out in this study. The mechanical model of the dampers is first introduced and the dynamic model of building-damper system is proposed. The evaluation criteria of energy responses are developed and applied to the earthquake response mitigation of a real multi-story building incorporated with friction dampers. The results indicate that the earthquake-induced vibration of the building can be substantially suppressed and the proposed energy evaluation criteria can be effectively utilized in the examination on seismic mitigation performance.