Advanced Materials Research Vols. 594-597

Abstract: The author did numerical experient on the seismic behavior of fram-surpported shear wall structure,then proposed a method of fuzzy neural network forrecast besed on second-time comprehensive evaluation for training and forecast with all these experiment mertiarials.The result shows that this method can forecast the seismic behavior of fram-surpported shear wall structure fairly well, which is avilable to this kind of sructure selection.

Abstract: The ridge topography can substantially influence seismic ground motion and, in general, causes the amplification of seismic ground motion amplitude at ridges. Fortunately, sets of three-component accelerogram, obtained by the observation arrays for topographic effect at Zigong Xishan, Jiangyou Doutuan and Qingchuan Sanguo from the great Wenchuan earthquake and its aftershocks, provided basic data for analyzing the effect of ridge topography on seismic ground motion. On the base of these acceleration records, peak ground acceleration and response spectrum ratios are calculated, and examined and compared in order to grasp the effect of ridge topography on ground motion. The findings showed that ridge topography has the remarkable effect on seismic ground motion, in which the amplification characteristics varies depending on the shape of ridge topography, and the amplification effect of the horizontal directions are not similar to the vertical direction, and in some periods are even less than 1.0.

Abstract: Comparing with direct storey-adding structure, storey-adding isolated structure has different effect to the seismic performance of original structure. By establishing a multi-mass dynamic analysis model of storey-adding isolated structure in which isolation devices were set up, the damping mechanism of storey-adding isolated structure with different amounts of added floors and various frequency of isolation layer was studied. The results show that, with the increasing of added floors, the inter-storey shearing force and inter-storey drift increased more obviously, and the isolation effect is more desirable when the frequency of isolation layer is lower than 50% of the site characteristic frequency.

Abstract: Aiming at the scientific goals of seismic resistance of bridge of pile foundation in liquefiable site, several scientific key problems were presented. Then, the following were analyzed in detail: Mechanism of large-scale table test on dynamic pile-soil-bridge interaction in liquefiable site; the Pyke’s modified dynamic constitutive model of soil; Kagawa’s p-y relation for analysis of piles lateral resistance behavior, and evaluation of degradation and velocity effect on piles vertical resistance. The results show that quasi-static and dynamic analysis need to be advanced for prediction of dynamic pile-soil-bridge interaction; the continuum media model based on Biot's dynamic coupled theory for two-phase porous media should be further developed; Kagawa’s p-y relation is the better choice for analysis of lateral resistance behavior of piles and should be improved, and liquefaction should be considered when analyzing the influences of degradation effect and velocity effect on the vertical resistance behavior of piles.

Abstract: In recent years,cold storage which is the central pivot of low temperature circulation of food developes faster overseas.It shows single-story and assembly and fast speed of low –temperature storage.In china it is being developed from multi-storey to single-storey of high goods shelves.Earthquake action of cold storage with reinforced concrete frame building is quantitatively analyzed by using three methods for bottom shearing and mode-superposition response spectrum and linear elastic time history analysis.Applicable condition of method for bottom shearing is verified.The paper aims to do the comparison and analysis of seismic precautionary of six or seven degrees,so as to provide some valuable references to the same type of buildings.

Abstract: Use of Seed’s simplified liquefaction evaluation method, combined with the dynamic triaxial test results, and the wave velocity of site liquefaction, to evaluate liquefaction potential of the three typical loess sites under the action of different seismic magnitudes, and calculate the boundary depth of the liquefaction site. Moreover, give the corresponding relationship between the typical loess site liquefaction boundary depth and shear wave velocity, and get the critical shear wave velocity of typical loess liquefaction site. The results of the study show that, (1) saturated loess site could be liquefied under the action of a certain intensity earthquake. (2) saturated soil layers which do not produce liquefied under the action of 6.5 degree earthquake，its critical shear wave velocity is about 200 m/s, and under the action of 7 degree earthquake its critical shear wave velocity is about 303 m/s, under the action of 8 degree earthquake its critical shear wave velocity is about 368 m/s. This conclusion enriches and develops the basis of liquefaction potential evaluation in the loess region.

Abstract: The Baisha river basin was extremely destroyed by the Wenchuan earthquake. This paper extracted the seismic-induced geological disasters data about 26km2 within an area of 368.25km2 by remote sensing interpretation and field investigation. This paper used arcgis to analysis these data, and divided the basin into several belts or zones base on slope, aspect, elevation and stratum lithology. The geo-hazard distribution analysis model was built to find some correlation between disaster distribution and geological factors such as terrain, stratum lithology and geomorphology by comparing among the parameters Ps, Ph, and Pc. The results show that most hazards occur where the slope between 30° and 50°, or aspect range is112.5° to 202.5°, and or the elevation between1140m and 3140m, the stratum lithology are the Huangshuihe group and The Middle Proterozoic common granite. At last the research zone is classified into four levels base on ground destroyed grade, and results show that the belts of most hazards located are not always the one destroyed most heavily.

Abstract: This paper introduces the concept and design method of the base isolation structure, through the SAP2000 software to analyze 6-story reinforced concrete frame for nonlinear time-history analysis, comparison of isolated and non-isolated structure's maximum displacement, acceleration under frequent earthquake and the maximum displacement, acceleration of isolation structure under rare earthquake. The results show that the isolated structure have a much better seismic responding than the traditional structures.

Abstract: "six two building" in ocean university of china has been used over 90 years, which can not meet the requirements for earthquake resistance protection. In order to ensure its safe use, at the same time keeping the original building style, this paper proposes the seismic appraisal method after field detection, structure calculation and appraisal regulation check. Then this paper presents corresponding strengthening suggestion. It can be used for reference in other similar old building.

Abstract: A theoretical analyzing approach about a novel tuned mass damper system, on high-rise building, was derived according to Lagrange Equation. The solution was programmed with MTALAB software based on the Longe-Kuta method. Computation results show that the displacement, the velocity, and the moment of the highest point were significantly decreased with this system. The system will exhibit the best efficiency with he slip friction factor being 0.01, the spring coefficient 10000KN/m,the damping coefficient 100000 KN/m s and the tuned mass 1.0 times of the mass of per length of the structure.