884aa四虎影成人精品,99久久国产综合精品女图图等你,97在线观看永久免费视频,久久精品国产精品亚洲38,ⅵdeodesetv性欧美

（湖南大學(xué)土木工程學(xué)院，長(zhǎng)沙 410082）

［摘要］通過(guò)脈動(dòng)試驗(yàn)獲得土-箱型基礎(chǔ)-框架結(jié)構(gòu)(比例1∶2)的自振頻率。利用有限元程序Patran建立了四種模型，包括：剛性地基桿系模型、剛性地基實(shí)體單元模型、地基A實(shí)體單元模型、地基B實(shí)體單元模型。利用Nastran程序分五種工況計(jì)算了以上四種模型的自振頻率，五種工況涵蓋了單元類型、網(wǎng)格密度、地基范圍、地基剛度、上部結(jié)構(gòu)剛度、結(jié)構(gòu)配筋率等多種因素的影響。結(jié)果表明：考慮土-結(jié)構(gòu)動(dòng)力相互作用時(shí)，建模中地基大小取值范圍與地基剛度有關(guān)，試驗(yàn)?zāi)Ｐ椭辛号浣盥蕦?duì)自振頻率的影響高于柱配筋率的影響。給出了不同種類場(chǎng)地土條件下剛性地基桿系模型的一階自振頻率調(diào)整系數(shù)。

［關(guān)鍵詞］脈動(dòng)試驗(yàn)；有限元建模；結(jié)構(gòu)自振頻率；上下部結(jié)構(gòu)相互作用；配筋率

Study on factors of FEM analysis in natural frequency for frame structure

Zhou Fen, Shang Shouping, Du Yunxing

（Civil Engineering College, Hunan University, Changsha 410082, China）

Abstract:The natural frequency of soil-box foundation-frame structure (1:2) was obtained by pulsateon test. Four models were created through FEM program Patran which included framed model with rigid subsoil, solid element model with rigid subsoil, solid element model with subsoil A and solid element model with subsoil B. Program Nastran was adopted to calculate natural frequency of four models in five subcases. The five subcases covered effects of factors such as element type, meshing density, subsoil size, subsoil stiffness, upper-structure stiffness and reinforcement ratio. Results show that when soil-structure dynamic interaction is considered, the range of soil size in FEM modeling is related to the distribution of subsoil stiffness. For different kinds of site soil, the adjusting factors of the first-order frequency in framed model with rigid subsoil are given. In this test model, the effects of beam reinforcement-ratio on natural frequency are larger than that of column reinforcement-ratio.

Keywords:pulsateon test; FEM modeling; natural frequency; upper-lower structure interaction; reinforcement ratio

*國(guó)家自然科學(xué)基金資助項(xiàng)目（50578062）；湖南省2007年度安全生產(chǎn)科技發(fā)展計(jì)劃項(xiàng)目（07-02）；湖南省科技計(jì)劃(2007RS4009)；湖南省科技計(jì)劃重點(diǎn)項(xiàng)目(06SK4057)。

作者簡(jiǎn)介：周芬，在讀博士，講師，Email:zhoufendu@163.com。