基于离心模型试验的海域软土场地设计反应谱特征分析  

Characteristic Analysis of Design Response Spectrum of Sea Soft Soil Site Based on Centrifugal Model Tests

作　　者：王婷 兰景岩[1,2] 宋锡俊 吴连斌[1,2] 蔡金豆 史庆旗 Wang Ting;Lan Jingyan;Song Xijun;Wu Lianbin;Cai Jindou;Shi Qingqi(College of Civil and Architectural Engineering,Guilin University of Technology,Guilin 514004,Guangxi,China;Guangxi Key Laboratory of Geotechnical Geomechanics and Engineering,Guilin University of Technology,Guilin 541004,Guangxi,China)

机构地区：[1]桂林理工大学土木与建筑工程学院,广西桂林541004 [2]桂林理工大学广西岩土力学与工程重点实验室,广西桂林541004

出　　处：《吉林大学学报（地球科学版）》2021年第5期1391-1399,共9页Journal of Jilin University：Earth Science Edition

基　　金：广西自然科学基金项目(2018GXNSFAA281183);广西高等学校千名中青年骨干教师培育计划项目(2020);广西岩土力学与工程重点实验室开放基金(桂科能19-Y-21-4);国家自然科学基金项目(52168067)。

摘　　要：为了揭示和掌握海域软土场地的地震动特征,给海域工程抗震设计提供科学可靠的设计反应谱,更好地服务于工程抗震设计,先设计并构建了上覆有水的海域饱和软土场地的离心模型,在100g的离心环境下开展了5组振动台试验,获取了不同强度地震输入条件下海底地表处的加速度结果;再以当前国内外普遍采用的3种设计谱拟合标定方法对加速度反应谱进行拟合回归,并对不同方法得到的拟合参数进行了对比分析。结果表明:我国现行建筑抗震规范设计谱与试验反应谱差异较大,标定的设计谱特征周期值明显偏小,对长周期工程抗震存在设计风险;而基于美国抗震规范的设计谱与试验反应谱具有良好的一致性,标定的设计谱特征周期较为合理,但设计谱平台值明显偏小,工程上也偏于不安全;中美两国规范设计谱均有各自的局限性。相比之下,薄景山团队提出的设计谱标定的工程方法和标定结果较为合理,设计谱特征周期与试验反应谱吻合度较高。In order to reveal and master the ground motion characteristics of marine soft soil site, to provide scientific and reliable design response spectrum as the basis for seismic design of marine engineering, better serve the engineering anti-seismic design, in this study, a centrifugal model of marine saturated soft soil site covered with water was designed and constructed. Five sets of shaking table tests were carried out under a 100g centrifugal environment, and the acceleration results at the seabed surface under different seismic input conditions were obtained;Three commonly used design spectrum fitting calibration methods were used to fit and regress the acceleration response spectrum, and the fitting parameters obtained by different methods were compared and analyzed. The results show that: There is a big difference between the design spectrum and the test response spectrum of the current building seismic code in my country, the characteristic period value of the calibrated design spectrum is obviously small, so there is a design risk for the seismic resistance of long-period projects;While the design spectrum and test response spectrum based on the U.S. seismic code have good consistency, the characteristic period of the calibrated design spectrum is relatively reasonable, but the design spectrum platform value is obviously too small, therefore the engineering is unsafe either. In contrast, the calibration results of design spectrum calibration proposed by Bo Jingshan research team are more reasonable, and the characteristic period of design spectrum is in good agreement with the test response spectrum.

关 键 词：海域饱和软土场地 动力离心模型试验 加速度反应谱 设计反应谱标定 

分 类 号：TU47[建筑科学—结构工程]