渤海导管架平台桩柱冰压力随机过程模型及其参数确定

首先分析了冰压力随机过程的特征及其产生机理,从而按冰的破坏形式将冰压力随机过程分为挤压破坏过程、屈曲破坏过程和弯曲破坏过程.从渤海海冰对平合桩柱作用大量实测冰压力曲线中选取37条典型的冰挤压破坏时程曲线,经谱分析确定了相应冰压力随机过程的谱密度及其谱参数;进一步经统计分析,建立了谱参数与冰厚的关系;在此基础上,建立了绕圆桩柱的冰压力随机场模型,并利用大量实测数据,经统计回归分析,确定了场函数的具体表达形式,由此用冰压力随机场可以容易地确定圆桩柱的总冰压力随机过程及其谱密度.

Stochastic process model of ice acting on upright column of marine platform and determination of model parameters

The characteristic and mechanism of ice force stochastic process (IFSP) are discussed first.IFSP is classified into crushing failure process,bulking failure process and bending failure process according to the failure mode of ice.After spectrum analysis of 37 pieces of ice force vs.time sampling lines in crushing mode,which are selected from the field data of ice force surveyed at the Bohai Sea area,the corresponding spectrum density and its parameters are determined.Through further statistical analysis the relationship between spectrum parameters and ice thickness is established.Based on this results,the stochastic field model of ice force encircling upright column is obtained.The function of statistical field is given through statistical regressive analysis to large amount of field data.The stochastic process of total ice force on upright column and its spectrum density can be conveniently determined from the stochastic field model.