﻿ 爆炸和高温联合作用下海洋平台结构动态响应研究
 舰船科学技术  2020, Vol. 42 Issue (10): 98-103    DOI: 10.3404/j.issn.1672-7649.2020.10.020 PDF

1. 江苏科技大学 船舶与海洋工程学院，江苏 镇江 212003;
2. 江苏科技大学 土木工程与建筑学院，江苏 镇江 212003

Research on the dynamic response of offshore platform structures under the combined explosion and high temperature
WANG Ke1, LI Jian-chao1, YIN Qun1, SHEN Zhong-xiang1, CAI Ai-ming1, CAO Hui-qing1
1. School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 China;
2. School of Civil Engineering and Architecture, Jiangsu University of Science and Technology, Zhenjiang 212003 China
Abstract: The Explosion and fire accidents are often caused by oil and gas leakage on offshore platforms, which pose a serious threat to the safety of platform structures and staff. In this paper, the closed compartment of a certain offshore platform is used as the research object, and the dynamic response of the offshore platform under the effects of explosion and high temperature loads is numerically simulated using MSC. Dytran. The damage mechanism and dynamic response law under the action of explosion and high temperature load provide a reference basis for the design and construction of offshore platforms.
Key words: offshore platform     fire explosion     dynamic response     numerical calculation
0 引　言

1 空中爆炸理论

 图 1 空中爆炸冲击波传播原理图 Fig. 1 Schematic diagram of air explosion shock wave propagation

Henrych在《爆炸动力学及其应用》[5]介绍了空中爆炸现象、空中爆炸载荷传播规律及其应用，提出空中爆炸冲击波载荷的Henrych经验公式。以TNT球形药包为例，冲击波瞬时压力与时间的关系为：

 $\Delta p(t) = \Delta {p_m}\left(1 - \frac{t}{\tau }\right){e^{ - \alpha t/\tau }},$ (1)
 $\begin{split}\frac{\tau }{{\sqrt[3]{W}}} =& {10^{ - 3}}(0.107 + 0.444\overline R + 0.264{\overline R ^2} - 0.129{\overline R ^3} +\\ &0.0335{\overline R ^4}),\;\;\;0.05 \leqslant \overline R \leqslant 3,\end{split}$ (2)
 ${{\Delta }{p_m} \!=\! \frac{{14.0717}}{{\bar R}} \!+\! \frac{{5.5397}}{{{{\bar R}^2}}} \!-\! \frac{{0.3572}}{{{{\bar R}^3}}} \!+\! \frac{{0.00625}}{{{{\bar R}^4}}},\;0.05 \!\leqslant\! \bar R \!\leqslant\! 0.3},$ (3)
 ${{\Delta }{p_m} = \frac{{6.1938}}{{\bar R}} - \frac{{0.3262}}{{{{\bar R}^2}}} + \frac{{2.1324}}{{{{\bar R}^3}}},\;\;\;\;\;\;\;\;\;0.3 \leqslant \bar R \leqslant 1},$ (4)
 ${\Delta }{p_m} = \frac{{0.662}}{{\bar R}} + \frac{{4.05}}{{{{\bar R}^2}}} + \frac{{3.288}}{{{{\bar R}^3}}},\;\;\;\;\;\;\;\;\;1 \leqslant \bar R \leqslant 10{\text {。}}$ (5)

 ${M_{ET}} = 6.4 \times {10^{ - 6}}M \cdot {H_c}{\text{。}}$ (6)

2 计算模型 2.1 有限元模型

 图 2 炸药位置示意图 Fig. 2 Sketch map of explosive location

 图 3 厚度分布示意图（半剖） Fig. 3 Distribution of thickness of platform（semi-section）

 图 4 有限元模型的约束条件示意图 Fig. 4 Boundary conditions of finite element model
2.2 流固耦合

 图 5 多欧拉域的有限元模型 Fig. 5 Finite element model of multi-euler domain
2.3 材料模型

 $\sigma {}_y = \left[ {\left. {1 + {{\left( {\frac{{\dot \varepsilon }}{D}} \right)}^{1/q}}} \right]} \right.\left( {{\sigma _0} + \beta {E_p}\varepsilon _p^{eff}} \right){\text{。}}$ (7)

 $P = \left( {\gamma - 1} \right)\rho e{\text{。}}$ (8)

2.4 计算工况

3 计算结果与分析

3.1 毁伤变形分析

 图 6 不同温度舱室结构毁伤应力图 Fig. 6 Structural damage stress diagram of bursting cabin at different temperatures

 图 7 不同温度舱室结构最大变形图 Fig. 7 Maximum structure deformation of explosion chamber at different temperatures
3.2 冲击环境分析

 图 8 不同温度上甲板中心点时间历程曲线 Fig. 8 Time history curve of upper deck center at different temperature

3.3 吸能分析

 图 9 不同温度结构吸能时间历程曲线 Fig. 9 Time-history curve of structure energy absorption at different temperatures

4 结　语

1）温度载荷对结构应变率强化效应影响不大， $\sigma_T /\sigma$ 随着温度的升高而略有增加。

2）温度对结构冲击环境影响较大，速度和加速度的振荡周期随着温度载荷的增加而增大；当结构温度超过400 ℃后，高温软化效果使得结构塑性变形能力增加，结构速度分布整体呈上升趋势，加速度波动范围减小。

3）当结构温度在低温阶段时，温度载荷增加对平台结构抗毁伤能力和冲击环境没有太大影响，主要考虑爆炸冲击波对其造成的毁伤破坏。

4）结构在“蓝脆”阶段整体表现较为稳定；但当温度载荷继续增加，平台结构抗爆、抗毁伤能力出现大幅削减，此阶段结构强度受高温载荷影响较大。

 [1] 于文静. 导管架海洋平台钢结构在爆炸和火灾作用下的力学性能研究[D]. 上海: 上海交通大学. 2012. [2] ZOHRA S. HALIM, JANARDANAN S., FLECHAS T., et al. In search of causes behind offshore incidents: Fire in offshore oil and gas facilities[J]. Journal of Loss Prevention in the Process Industries. 2018.54: 254-265. [3] YIN Qun; CAO Guangbo; XIE Renjie. et al. Research on a ship bulkhead structure under the combined load. Hydraulic Engineering V - Proceedings of the 5th International Technical Conference on Hydraulic Engineering[C], CHE 2017. [4] Y. L. LIU, A. M. ZHANG, Z. L. TIAN, et al.. Numerical investigation on global responses of surface ship subjected to underwater explosion in waves[J]. Ocean Engineering, 2018, 161: 277-290. DOI:10.1016/j.oceaneng.2018.05.013 [5] HENRYCH J, ABRAHAMSON G R. The dynamics of explosionand its use[M]. Amsterdam Elsevier Scientifi Pub. 1979. [6] EMI Yohiko. Research on the Safety of Liquid Gases [A]. Proceedings of the Japan Shipbuilding Association[C], No. 156, Showa 59. [7] NEN-EN1993-1-2. Eurocode3: Design of Steel Structures Part1-2: General Rules Structural Fire Design. Brussels: European Committee for Standardization, 2005. [8] 王培涛. FPSO油气爆炸性能评估及抗爆结构设计研究[D]. 镇江: 江苏科技大学. 2016. [9] 胡云昌, 黄海燕, 余建星. 基于概率影响图的海洋平台安全风险评估方法[J]. 中国造船, 1998, 1429(3): 38-46.