风沙侵蚀下GFRP布剩余力学性能数值模拟分析

NUMERICAL SIMULATION OF RESIDUAL MECHANICAL PROPERTIES OF GFRP STRIPS UNDER BLOWN-SAND EROSION

  • 摘要: 为了探究玻璃纤维增强复合材料(GFRP)布的抗风沙侵蚀性能,以侵蚀速度和时间为变量,完成了经风沙侵蚀后GFRP布的剩余力学性能试验以及相应的有限元数值模拟分析。扫描电镜测试结果表明,随着侵蚀速度和时间的累积,GFRP布的损伤破坏加剧,环氧胶层易发生剥落,内部纤维则发生断裂。通过风沙侵蚀后的剩余力学性能测试发现,GFRP布的破坏均表现为脆性受拉断裂。随着侵蚀速度的增加,试验试件峰值荷载的最大降幅约为25%;而随着侵蚀时间的累积,试验试件极限荷载的降幅可达到36.4%,侵蚀速度和时间均会不同程度地削弱GFRP布的整体受力性能,进而显著影响其剩余力学性能。采用狄拉克函数对风沙侵蚀荷载进行等效化处理,建立了关于GFRP布经风沙侵蚀后的有限元数值分析模型,通过试验结果验证了模型的可靠性。基于有限元模型,进一步针对侵蚀速度和时间进行参数分析,可知随着侵蚀速度和时间的增加,GFRP布的劣化速率大大加快。

     

    Abstract: In order to investigate the blown-sand erosion resistance of glass fiber reinforced polymer (GFRP) strips, the experimental research and finite element numerical simulation analysis on the residual mechanical properties of GFRP strips had been completed by taking the erosion velocity and time as the variables. The scanning electron microscope test results indicated that with the increase of the erosion velocity and time, the damage and destruction of the GFRP strips enhanced. Moreover, the epoxy adhesive was prone to peeling off, and the internal fibers might undergo fracture. Through the residual mechanical property test on the GFRP strips after blown-sand erosion, it could be found that the failure of GFRP strips was characterized by brittle tensile fracture. As the erosion velocity went up, the maximum degrease in the peak load of the test specimens was about 25.0%, while with the accumulation of the erosion time, the ultimate load of the GFRP strips could decrease by 36.4%. And the erosion velocity and time would deteriorate the overall mechanical properties of GFRP strips to different degrees. Therefore, the residual mechanical properties of GFRP strips could be affected obviously. A finite element model of GFRP strips after blown-sand erosion was established by the equivalent treatment of blown-sand erosion loading using the Dirac function. And the reliability of the model had been verified through the experimental data. Based on the newly proposed numerical model, parameter analysis had been conducted on the erosion velocity and time, and it could be acquired that as the erosion velocity and time increased, the degradation rate of GFRP strips accelerated considerably.

     

/

返回文章
返回