Papers by Keyword: Wenchuan Earthquake

Abstract: Slope dynamic factor of safety (FOS) under earthquake was calculated based on time history analysis method and compared with acceleration time history to analyze correspondence between them. In view of the fact that earthquake is a dynamic process, this paper proposed that three respects can be considered to analyze the slope stability rather than adopting a single FOS value. Firstly, the variation trend of the FOS time history can be combined with the forces on key points to analyze slope stability. Secondly, the displacement and stress vector fields can be adopted to evaluate the final slope stability. Thirdly, the variation trend of the displacement and velocity time history can be used as well. The above methods are applied to Beihoushan landslide in Hanyuan in Wenchuan earthquake to evaluate slope stability under earthquake and the analysis shows that the slope is stable as a whole.

Abstract: Saturated soil liquefaction of macroscopic signs are surface sand boil, ground pavement cracks, landslides, farmland covered by sand, foundation is not uniform settlement led to the building sink and even cause damage to buildings and other instability. The phenomenon of soil liquefaction damage occurred many times at home and abroad in the earthquake history. By the research of the future, this paper combs the domestic and foreign typical seismic liquefaction phenomenon and refining mechanism of soil liquefaction.

Abstract: The strong effect on ground damage and the serious earthquake-induced geological disasters are notable features of MS8.0 Wenchuan earthquake. This study obtained 993 earthquake geological disasters in Wudu District and Wenxian County of Gansu Province, by combining field investigation and interpretation of remote-sensing images. Then the characteristics of these geological disasters were investigated statistically using GIS techniques to determine how the occurrence of geological disasters correlated with intensity, distance from the rivers, slopes and elevations. The main results can be summarized as follows: (1) the geological disasters density increased with the increase of earthquake intensity; (2) the geological disasters triggered by earthquake show the feature of zonal distribution along the rivers; (3) the slope steepness is the main factor which controls the development of earthquake-induced geological disasters and most of the geological disasters are distributed with the slopes of 10 to 40 degree; (4) the earthquake-induced geological disasters have corresponding relationships with elevations, and most disasters occur with the elevation of 1000 to 2000 m.

Abstract: The curved bridges suffered severe damages or even collapsed during 2008 Wenchuan Earthquake. A field survey of seismic performance of RC curved bridges was examined. Damage patterns and the probable causes of RC curved bridges including Baihua bridge and ramp bridge of Huilan interchange are presented and analyzed in this paper. The main failure was pure shear failure or shear-flexural failure of the pier columns. Bearings and expansion joints damage were another common failure pattern. Lesson learned from the damage of RC curved bridges in this earthquake, the recommendations on the seismic design of RC curved bridges are presented involving ductility of bridge columns, design of curved bridges, design of bearings and devices preventing girders falling down. Suggestions for the future seismic design and retrofitting of RC curved bridges are also presented in moderate to severe earthquake area.

Abstract: The Wenchuan earthquake occurred on May 12, 2008 (Beijing Time) caused great casualty and economic losses, a large number of masonry buildings were damaged in various degrees in this earthquake. The masonry residential buildings are widely used in China, and the study on them is significant. Although the masonry residential building discussed in this paper which was located in the highly intensity region was damaged severely, it hasnt collapsed and has very typical earthquake damage. The story comprehensive seismic capacity indexes are developed to anti-collapse capacity index which are used to calculate anti-collapse capacity of the building, and the results are also used for comparative analysis with the results calculated by means of structure vulnerability analysis. The earthquake resistant capacity of masonry residential buildings are discussed and analyzed. Finally, some reasonable suggestions on the seismic strengthening and reconstruction of this kind of building after disaster have been given.

Abstract: The health diagnosis of seismic-damaged tunnel seismically damaged is important in recovering traffic lines for seismic relief and recovery. Taking a tunnel damaged tunnel in the Wenchuan earthquake as an example, the methods of safety check is exposed. The non-destructive test showed that the seismic damage to this tunnel included concrete cracks, hidden cavities, and strength deterioration of lining. Several causes induced in seismic diseases were discussed. The rehabilitation technique, which needs not break off transportation through the tunnel, was also put forward. It is hoped that this earthquake mechanics study can enhance the stability assessment and tunnel reinforcement in a highly seismic region.

Abstract: 5·12" Wenchuan earthquake resulted in a large number of secondary mountain disasters, serious damage to ecological environment and cultural landscapes. By building evaluation index system of residential environment, the paper compares to residential environment before and after Wenchuan earthquake in Weizhou town.

Abstract: After the Wenchuan earthquake, a number of minority villages face many difficulties in relocation due to their poor geographical location, backward economic development and poor inhabited environment. In this paper, successful pattern for relocation of minority villages are researched and explored through analysis, generalization and summation with the post-disaster relocation of Yangliu Village in Taiping Township of Mao County as an example, in order to provide reference for the reconstruction of other minority villages stricken by the great disaster.

Abstract: This work is based on a typical RC frame that was closed to the epicenter and collapsed during the Wenchuan Earthquake. The seismic collapse resistance of the frame was strengthened by attached substructures, including conventional brace, buckling restrained brace (BRB) and viscous damper. Collapse fragility analysis based on incremental dynamic analysis is implemented for each strengthening scheme to compare their effects and to analyze the influence of critical parameters. The results show that the viscous damper performs better than the BRB, and the BRB performs better than the conventional brace. With the same strengthening parameters, the A-shaped bracing scheme is better than the X-shaped scheme.

Abstract: In order to study the characteristics of ground motions at the two dam sites damaged during the great Wenchuan earthquake in 2008, the motions at two observation stations nearby are synthesized in this paper. 30 finite fault based hybrid source models of the great Wenchuan earthquake with magnitude 8.0 is built. The global and local parameters are both generated from the truncated Normal distribution with mean and standard deviation values estimated by a set of semi-experiential calibration laws and from the regional seismo-tectonics, structure of the crust, and seismicity. A representative source model is then chosen from the corresponding response spectrum mostly close to the average one. The result motions are presented, and the characteristics of the time histories, response spectra and the peak accelerations are quite close to the recordings.