直角梯形ETFE气枕塑性成形试验与数值分析研究

Plastic-forming experiment and numerical analysis of right angled trapezoid ETFE cushions

摘要:

ETFE薄膜材料具有良好的塑性性能,利用这一性能,ETFE气枕可以进行基于平面裁剪的塑性成形。本文制作了两个直角梯形ETFE气枕模型,设计了气枕充气泄气压力控制系统,对两个气枕分别进行充气成形试验和循环充气加载试验,利用激光位移计对膜面位置进行测量。试验结果表明,经过2kPa内压的塑性成形,得到的两个气枕的矢跨比分别为1/9.4和1/10.3,成形过程使ETFE薄膜材料发生强化。本文采用多折线各向同性强化的弹塑性材料模型模拟ETFE薄膜,采用ANSYS软件进行了气枕成形以及循环加载的数值分析,并对数值分析结果与试验结果进行了对比分析。

关键词:ETFE气枕,塑性成形,平面裁剪,充气试验,数值分析

Abstract:

Plastic-forming based on plat-patterning is applicable to ETFE cushions owing to good plasticity property of ETFE foils. Two right angled trapezoidal ETFE cushion models are designed and manufactured. Cushion forming and cyclic inflating-deflating tests of the two ETFE cushion models are carried out by employing a pressure control system. Vertical displacements on the lower surface are measured by laser displacement transducer. The results indicate that rise-to-span ratios of the two cushions are respectively 1/9.4 and 1/10.3 under the condition that the maximum internal pressure of plastic-forming is 2kPa. In addition, the ETFE foils are strengthen during the forming process the. A multi-linear elastic-plastic model with isotropic hardening in ANSYS is employed in numerical analyses of the forming and cyclic inflating-deflating processes, and the results are compared with the experimental data.

Key words:ETFE cushion; plastic-forming; plat-patterning; inflating and deflating test; numerical analysis