Recommended Finite Element Formulations for the Analysis of Offshore Blast Walls in an Explosion

Abstract This study suggests relevant finite element (FE) formulations for the structural analysis of offshore blast walls subjected to blast loadings due to hydrocarbon explosions. The present blast wall model adopted from HSE (2003) consists of a corrugated panel and supporting members, and was modelled with shell, thick-shell, and solid element combinations in LS-DYNA, an explicit finite element analysis (FEA) solver. Stainless and mild steels were employed as materials for the blast wall model, with consideration of strain rate effect throughout ten (10) pulse pressure load regimes. The obtained FEA results were validated by experimental data from HSE (2003) with decent agreement. In the present study, recommended FE formulations with additional hourglass control functions were widely discussed from the perspectives of solution accuracy and computational cost based on a statistical approach. The obtained outcomes could be used for the structural analysis and design of offshore blast walls in the estimations of maximum and permanent deformations under blast loadings.

摘要 本研究针对烃类爆炸引发的爆破载荷作用下的近海防爆墙结构分析，提出了适用的有限元（Finite Element, FE）建模方法。本次研究采用的防爆墙模型源自HSE（2003），由波纹板与支撑构件组成，借助显式有限元分析（Finite Element Analysis, FEA）求解器LS-DYNA，采用壳单元、厚壳单元与实体单元的组合形式完成建模。研究选取不锈钢与低碳钢作为防爆墙的材料，并在10种脉冲压力载荷工况中考虑了应变率效应的影响。所得有限元分析结果通过HSE（2003）的实验数据进行验证，二者吻合度良好。本研究中，基于统计方法从求解精度与计算成本两个维度，对引入额外沙漏控制功能的推荐有限元建模方法展开了充分讨论。本研究所得结果可用于近海防爆墙的结构分析与设计，以预估爆破载荷作用下的最大变形与永久变形。