拉压不同模量的缝合三明治夹芯结构梁弯曲性能
Flexural properties of stitched sandwich structure beam with different modulus in tension and compression

为了建立具有不同拉伸和压缩弹性模量的缝合三明治夹芯结构梁的中性层位置和弯曲刚度的理论预测方法,并进行相关试验验证。首先,将缝合三明治夹芯结构梁看成准层状结构,考虑其拉压不同模量及材料上下面板几何尺寸不同的特点,基于修正的Reissner层板理论,建立了弯曲刚度和中性层位置的理论预测方法;其次,开展了缝合三明治夹芯结构梁的三点弯曲试验,并采用数字图像相关(DIC)法测试了中性层位置;最后,对弯曲刚度和中性层位置进行了理论预测。结果表明:理论预测值与试验结果吻合较好,证明了该理论预测方法的有效性。 In order to establish a theoretical prediction method of position of neutral plane and flexural stiffness for stitched sandwich structure beam with characteristics of different elastic modulus in tension and compression, and verify the effectiveness of the method through related experiment. Firstly, the stitched sandwich structure beam was looked as a quasi-layered structure, taking the characteristics of different modulus in tension and compression as well as different geometry on the top and bottom panel of materials into consideration, a modified Reissner plate theory was developed to evaluate the flexural stiffness and neutral plane position. Secondly, three-point flexural test of stitched sandwich structure beam was carried out, and digital image correlated (DIC) method was also adopted to measure the position of neutral plane. Finally, theoretical predictions were performed for flexural stiffness and position of neutral plane. The results show that theoretical prediction values are in good agreement with experimental data, which demonstrate the validity of the theoretical prediction method. 国家自然科学基金(51275023)