考虑液固耦合的三维水池地震动力性能研究

市政贮液构筑物中的液体在地震作用下会发生波动晃漾,产生的液动压力和冲击作用对结构动力特性和地震响应有明显的影响。本文以实际工程中的二沉池结构为例,建立包含流体和考虑与结构相互作用的三维数值模型,与现有规范对比验证了计算模拟方法的正确性和精确性,研究了结构径高比、储液量对结构地震动力性能的影响,讨论了三种地震波作用下水池不同高度处的动力响应,数值分析结果显示径高比、储液量对结构动力性能有明显的影响,地震激励作用下的水池底部和中部液动压力和弯矩相对较大,设计时应综合考虑合理选取结构参数和配筋。

小山口水电站混合坝插入式接头有限元分析

小山口水电站为面板坝和重力坝组合而成的混合坝,鉴于混合坝连接处易产生集中渗流和不均匀沉降问题,为了验证接头安全性,文章通过建立面板堆石坝、重力坝接头部分的整体模型,采用三维有限元进行静、动力计算,并对坝料参数进行敏感性分析。结果表明,满蓄期、地震期接头部位坝体和坝基应力、位移均满足规范要求,变形规律合理,证明接头方案可靠。在此基础上,给出了混合坝接头部位填筑和抗震措施的优化建议,为工程的设计提供重要依据。

Experimental and numerical analysis of submerged floating tunnel

As a new type of structure which has never been built, submerged floating tunnel was studied mainly by numerical simulations. To further study the seismic response of a submerged floating tunnel, the first model experiment of submerged floating tunnel （SFT） under the earthquake was carried out on the unique underwater shaking table in China. The experimental results show that vertical excitation induces larger response than horizontal and different inclination degrees of the tether also cause different seismic responses. Subsequently, based on the fluid-structure interaction theory, the corresponding numerical model is established. And comparing the numerical results with the experimental results, those of shaking table test. Numerical model adopted is effective for it is shown that the numerical results are basically identical with dynamic response of SFT.

Preliminary Analysis of the Relationship between the Magnitude Deviation of the Station and Site Response in the Fujian Digital Seismic Network

Using the records of 3,069 regional earthquake events from the Fujian Digital Seismic Network from October 2008 to December 2015,in which the magnitude of each of the events was measured by at least six stations,statistics are taken on the deviation between the magnitude of a single station and the average magnitude of the network. It is found that the magnitudes average deviation of each station is-0. 31-0. 68. Statistics are also taken for the period corresponding to the maximum amplitude of the record measured in each station for calculating the magnitude,and the dominant period gained is 0. 06s-0. 38s; site response of each seismic station is inverted using the Moya method,and it is found that the site response of 98 stations is in the bands of 1-20 Hz,suggesting that the site has an amplifying or suppressing effect on the signals in certain frequency bands;Considering the site response corresponding to the inherent 0. 8s period of the WoodAnderson pendulum seismograph,and comparing the magnitude deviation caused by the site response corresponding to the dominant period time of each station with the average magnitude deviation, we obtain that there is a good linear relationship between the magnitude deviation from the dominant period site response and the average deviation of the magnitude of each station,indicating that the magnitude deviation of a single station has a close relationship with the site response of the period corresponding to the maximum amplitude measured for calculating the magnitude.

Seismic performance of isolation system of rolling friction with springs

In order to study an isolation system of rolling friction with springs, computer programs were compiled to evaluate the seismic performance based on its movement characteristics. Through the programs, the influences of various seismic performance factors, e.g., rolling friction coefficient, spring constant, were systematically investigated. Results show that by increasing the rolling friction coefficient, the structural relative displacement due to seismic load effectively decreases, while the structural response magnitude varies mainly depending on the correlations between the following factors: the spring constant, the earthquake intensity, and the rolling friction coefficient. Furthermore, increasing the spring constant can decrease the structural relative displacement, as well as residual displacement, however, it increases the structural response magnitude. Finally, based on the analyses of various seismic performance factors subjected to the scenario earthquakes, optimized theoretical seismic performance can be achieved by reasonably combining the spring constant and the rolling friction coefficient.

Earthquake Response Characteristics of Contained Masonry Infilled Frames

The strength and stiffness contribution of infill masonry is generally ignored in the design, due to the uncertainty in the strength properties of masonry, separation of infill from frame, low tensile strength, brittle characteristics of masonry walls, less out of plane strength and stiffness, etc.. They are considered as nonstructural elements which is reasonable for the frames under gravity loads but it is not true for the frames under seismic loads. Contained masonry as infill in RC （reinforced concrete） frames provides better contact at the interface and a higher out of plane strength and stiffness. Considering the seismic action on the frames which are likely to be subjected to in-plane as well as out of plane shaking, a research work has been carried out by the authors to investigate the seismic performance of RC frames with and without contained masonry infill panels using FE （finite element） computer program （ANSYS-Ver. l 1） and experimentally using the tri-axial shake table to evaluate the methods proposed in IS-1893-2002 to calculate the fundamental natural frequency. The RC frames were designed and detailed as per IS （Indian Standard） specifications such as IS 456-2000, IS 1893-2002 and IS 13920-1993. Based on the experimental and analytical investigations, the contained masonry infill panels significantly affect the seismic load resisting characteristics of the RC frames. The IS 1893-2002 formulation does not predict the values and hence the recommendation needs to be validated with experimental results.

金沙江大桥抗震设计研究

金沙江大桥主桥为 156.50 m+ 3 2 4.0 0 m+ 156.50 m的三跨连续预应力混凝土斜拉桥 ,采用双塔双索面全飘浮体系。由于桥位处抗震设防烈度较高 ,又是跨越金沙江的特大型桥梁 ,其抗震性能尤为重要。本文结合金沙江大桥的抗震设计 ,从地震输入、地震响应计算。

高温气冷堆核岛厂房抗震设计研究

高温气冷堆(HTR-PM)核岛厂房采用钢筋混凝土板壳结构,抗震分类为Ⅰ类(C-I)。以核岛厂房在遭遇极限安全地震动(SL-2)(万年一遇)结构处在基本弹性状态、遭遇运行安全地震动(SL-1)(500年一遇)及其以下时结构处在安全弹性状态作为抗震性能目标。通过对剪力墙进行拟静力试验获得层间位移角限值,并以此做为结构性能控制指标;同时提出核岛厂房地震响应计算方法、钢筋混凝土板壳结构平面内承载力计算式。采用以上抗震性能目标及设计方法对核岛厂房进行了抗震设计。最后,通过振动台试验,证明采用所提的设计方法进行抗震设计的核岛厂房,其结构抗震性能良好,能够满足核安全功能要求。所提的钢筋混凝土板壳结构平面内承载力计算式已被相关标准采纳。