Applied Mechanics and Materials Vols. 580-583

Abstract: Self-Centering structure is a kind of new structure, which aims for reducing the residual deformation of structure after the earthquake. In order to research the Seismic Behavior of Self-centering Prefabricated concrete frame, a new joint applied with prestressed tendons and a traditional joint are designed in this paper with the finite element software ABAQUS. The seismic performances of them are contrastively analyzed. The new joint is found to have better self-centering capacity. Then two plane frame models are analyzed. The result shows that the frame applied with prestressed tendons has some capacity of self-centering and enough energy dissipation effects.

Abstract: This paper mainly discusses that the tunnel seismic advance detection is applied in mine geo-hazard detection. Separating the field seismic data of mine by radon transformation and migrating the data through advance way and side way, we accomplished advance and side detection simultaneously by one-time shot seismic data. Case study was carried on at Qinshui basin Yangmei No.5 mine field, and detection results mainly coincide with out-crops, demonstrating that our method can be one reference in mine geo-hazard detection.

Abstract: Swing structure is added to the current frame structure for forming the new swing structure system. In this paper, by taking the existing structure as an example, the anti-seismic performance of the new swing system is analyzed with pushover method and the current earthquake resistant design code, and influence of swing rigid frame with different stiffness ratios on the anti-seismic performance of the new structural system is discussed. According to the results, by setting swing rigid frame with different stiffness ratios, it can enhance the bearing capacity and ductility of the structural system remarkably, coordinate the deformation model of the structural system, give full play to the energy-dissipating capacity of the structure, and improve the anti-seismic performance of the structure.

Abstract: Qinghai is a multi-ethnic region, mainly living in the eastern agricultural areas Han, Hui and Tu, mainly living in the southwest area of animal husbandry Tibetan and Mongol. In order to adapt to the cold, arid, windy and long sunshine time climate of Qinghai, people created a unique style of traditional vernacular dwelling, Zhuangke. This unique architectural form is mainly with wooden frame bearing, matching with brick walls or rammed earth walls. Such buildings are mostly villagers themselves built according to past experience; do not involve seismic design, resulting in a great security risk. Through the field investigation of ten natural villages, this article has a deep understanding of the seismic performance of Zhuangke. Based on survey data, this paper presents its structural safety and seismic performance problem.

Abstract: The uncertainty of ground motion attenuation and its correction in PSHA is deal with in this paper. Mean values and standard deviations of random errors of three attenuation relationships of NGA-west1 are analyzed statistically from the data base released by the project. The dependences of the mean and deviation on magnitude, distance and peak ground acceleration are checked by the data base. The fact of mean values varying with acceleration is revealed obviously. Ground motion parameter Y is adopted into the probability density function of random error in a form of subsection. Finally, a suggestion to improve the correction is presented as subsection correction in the paper. The result of a case study by suggested procedure shows that the corrected acceleration is slightly higher than that of the traditional correction at the start of hazard curve, and is significantly lower than that of the traditional correction at the end of the curve, if the mean of random error decreases with acceleration.

Abstract: Non-engineered buildings are most of self-built house, which locate in rural area in China. The structural defect of non-engineered buildings could reduce seismic capacity. The damage of these buildings are the main cause of earthquakes casualties and economic losses. The main types of the building structures include the wooden house, soil and wood house, brick and wood house and masonry house. It is the seismogenic provincial regions for Xinjiang, Qinghai, Gansu and Yunnan in China. Based on the four type houses in the four regions, 104 earthquake disaster loss reports were selected from 1990 and 2013. This article focused on the analysis of house damage data. This article proposes "the average damage ratio" concept, which takes one provincial region as an area and studies the whole area data. Due to a combination of multiple and differenteffects of earthquakes within one provincial region, the average damage ratio can be on behalf of the damage ratio, and reflects the non-engineered building characteristics in the provincial region. And then the article demonstrates that the earthquake damage matrix of different house types in these four provinces area. The earthquake damage matrix provides a more reliable basis for the earthquake disaster evaluation in rural area.

Abstract: The bottom frame structure, with serious earthquake damage, occupies a large proportion in the houses collapsed in earthquakes. However, because it is economic and practical, it is still widely used. Based on the understanding of the seismic performance of bottom frame structure, this paper determines to study seismic measures of the bottom frame structure. The current seismic measures can be divided into two major categories: strengthening key components and avoiding key components, therefore this paper adopts the method of strengthening parts which are easy to collapse for reinforcement, under the premise of meeting the stiffness ratio between reasonable layers, adds wing wall to improve the capacity of resisting collapse of the structure and pinpoints the efficiency of adding wing wall in the capacity of resisting collapse through quantitative analysis. Although there are differences in the improvement of the capacity of resisting collapse under different seismic waves, adding wing walls reasonably can greatly improver the anti-collapse capacity of the structure..

Abstract: ANSYS was used to focus on comparative analysis of several artificial boundary conditions that are widely used in engineering applications. The accuracy and stability of dynamic analysis results were then analyzed in details of a semi-infinite foundation with different artificial boundaries and different frequency input loads. Lastly, the seismic response of a gravity dam-foundation rock system was explored numerically. Experimental results revealed the simulation accuracy of artificial boundaries was closely related to the dynamic characteristics of input load and the elastic wave velocity. When the input load frequency was high, only the material with comparably higher elastic wave velocity could maintain the stability of the artificial boundary. Viscoelastic artificial boundary is practically simple and can better simulate the semi-infinite material elastic recovery ability and energy radiation outside the boundary.

Abstract: The seismic response of the Wusong bridge was analyzed though the response spectrum method and the time-history method by adopting the MIDAS/CIVIL. The analysis results show that the longitudinal displacement of the main girder is much larger under longitudinal seismic input, so some inhibiting device or dampers should be used to avoid impacting. There is not coupling between longitudinal and lateral seismic excitations, while the seismic response of moment and shear force at the bottom of the main tower is much larger. On the contrary the seismic response of main beam and the main cable should be calculated under the longitudinal and vertical seismic excitations because of the coupling between the both of them. Furthermore, the artificial seismic wave fitting standard response spectrum was generated to conduct the time-history analysis and the results are much larger than the results from the response spectrum method.

Abstract: In order to study the effect of hydrodynamic pressure acted on pile-pier structure in deep water, an investigation on the inertial coefficient is developed. Based on the Morison equation, the usual suggested value is analyzed, especially the noncircular slender cylinder is considered. Besides, the effect of scale of structure is studied, including accurate algorithm and approximation algorithm. Study results indicate that the Morison equation is also applied to noncircular slender cylinder, and the value of inertial coefficient is influenced by the scale of structure. Moreover, the calculated results of accurate algorithm and approximation algorithm are consistent within a certain range, so the choice of calculation method should be governed by the required precision.