高桩码头Pushover分析影响因素研究

非线性静力分析方法或Pushover分析方法是近年提出并在高桩码头抗震设计中得到应用的位移计算方法,该方法将Pushover曲线与反应谱相结合对结构位移进行估计。探讨了影响高桩码头Pushover分析结果的因素,对Pushover分析的能力谱法和N2法及能力谱法中采用的不同等效线性化方法、等效阻尼比公式和不同反应谱进行了定性和定量分析,同时通过一个实际工程案例,比较了上述不同情况的目标位移计算结果。研究表明,能力谱法与N2法的计算结果之间存在差异,差异的大小与能力谱法采用的等效阻尼比计算公式有关;能力谱法中,不同等效阻尼比公式和反应谱曲线下降段的形状对高桩码头目标位移的计算结果有较大影响;Pushover曲线双折线化方法对位移计算结果的影响不是很大。

Influencing factors of Pushover analysis for open type wharf with standing piles

The nonlinear static analysis method or Pushover analysis method, coinciding with the response spectrum, is of the methods developed in recent years for quantifying the displacements and has been widely applied to seismic design for the open type wharf with standing piles. The factors influencing the estimation outcome by this method is clarified, and the qualitative and quantitative analyses are made between the capacity spectrum method and N2 method as well as the linearization procedures, equivalent damping ratio equations and response spectra used in the capacity method. A case study of the open type wharf with standing piles is conducted for the target displacement estimation to investigate the influences of the above mentioned factors. The analysis results show that there exist differences between the outcomes of the capacity method and N2 method and that the extension depends on the equivalent damping ratio equations used in the capacity method. For the capacity spectrum method, a great discrepancy arises from the equivalent damping ratio equations and the shape of descent branch of the response spectra, and the linearization method of Pushover curve has played a minor role, that has no great influence upon the calculated results for the displacements.