摘要
在船体极限强度的研究中,对船体到达极限强度后的剩余承载能力的研究非常重要,其关系到船体结构的生命力设计,用于判断船舶破损情况下是否还能保持一定的自存能力,制定救援方案以及作为船舶在极端情况下安全性的判断依据。目前此类研究多是针对单次加载,而在实际海洋环境中,船舶会受到交变载荷的作用,如果超过弹性范围,会留下塑性应变,这些残留应变会影响船舶最终承载能力的大小。本文以逐步崩溃法为基础,用Fortran语言开发了计算程序,该程序可以得到船体梁在极限强度后的承载能力,同时通过递增塑性法来模拟循环加载带来的影响,并采用非线性有限元法进行对比验证。
After imposing the longitudinal ultimate strength, the capacity of ship will be changed due to obviously nonlinear deformation. At present, the residual capacity of ship is very concerned in the study of hull girder strength. And the residual strength will be changed strongly under cyclic loading. In this paper, the nonlinear FEM calculations under cyclic loading of box beams and some real ships have been carried out by Abaqus respectively, to obtain moment-curvature curves, and based on the analysis of the incremental plastic method and the progressive collapse method, a calculation program have been developed, it can analysis the residual carrying capacity of hull girder under cyclic bending loads, then compare it to the FEM calculations' results.
引文
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