抓斗卸船机钢结构应力谱统计方法

Statistical methods for steel structure stress spectrum of grab ship unloader

以某码头1 800 t/h牵引式抓斗卸船机为研究对象,首先通过有限元分析软件Ansys对卸船机进行建模计算,确定结构的静载应力以及动载应力测点;然后模拟其真实卸船作业的典型工况,采用应变电测法对相关测点的动载应力进行实时数据采集;最后根据抓斗船型及抓取量对应力谱的影响,对卸船机钢结构应力数据进行统计分析,得到钢结构测点对于各种船型整个工作循环的应力谱,结合各船型到港次数,进而可以推算出卸船机钢结构测点全年的应力谱,为疲劳寿命评估打下了基础。

Taking the 1 800 t/h traction type grab ship unloader used at a terminal as the study object,the paper,at first,applies modeling calculations to ship unloader with the finite element analysis software Ansys,to determine the measuring points for static load stress and dynamic load stress of the structure;then,simulates the typical conditions of real unloading operation,to conduct real-time data acquisition of dynamic load stress at relevant measuring points with strain electrical measurement method;finally,based on the impact imposed by the grab ship type and the grab capacity on the stress spectrum,carries out statistical analysis of the ship unloader steel structure stress data,obtaining the steel structure measuring point stress spectrum during the entire working cycle of various ship type,combined with the number of arrival ships,thus the annual stress spectrum at measuring points of ship unloader steel structure can be worked out,providing a foundation for fatigue life assessment.