There are situations where geotextiles are subjected to uniaxial tensile strain, which may result in noticeable variations in their filtration performance. This study accordingly investigated the behaviors of needle-punched nonwoven geotextiles during tensile testing using in-situ X-ray computed tomography. Furthermore, a numerical analysis of the variation in pore size characteristics was performed by establishing a geotextile model based on the web formation and bonding manufacturing process. The pore size and fiber orientation distributions were subsequently investigated and a model for the changes in the pore characteristics was established and validated. With increasing tension strain in the machine direction, the pore throat size distribution curve exhibited an overall shift towards larger sizes, and the characteristic pore sizes ranging from 10% to 98% either initially decreased, then increased or consistently increased. Furthermore, the fiber distribution was predominantly within the geotextile plane along the machine direction, and as the strain increased, the fibers stretched and aligned along the direction of the tensile load along the machine direction. Finally, the experimental findings of this study and relevant test results from the literature were thoroughly interpreted. The numerical model align well with the actual changes in pore size characteristics observed under tensile strain.

中文翻译：

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基于原位X射线计算机断层扫描和数值模拟的针刺非织造土工布拉伸行为


在某些情况下，土工织物会受到单轴拉伸应变，这可能会导致其过滤性能发生明显变化。因此，本研究利用原位 X 射线计算机断层扫描研究了针刺非织造土工织物在拉伸测试过程中的行为。此外，通过建立基于成网和粘合制造工艺的土工织物模型，对孔径特性的变化进行了数值分析。随后研究了孔径和纤维取向分布，并建立并验证了孔隙特性变化的模型。随着纵向拉伸应变的增加，孔喉尺寸分布曲线呈现出整体向较大尺寸移动的趋势，并且特征孔径范围从10%到98%要么先减小，然后增大或持续增大。此外，纤维分布主要在沿机器方向的土工织物平面内，并且随着应变的增加，纤维沿着机器方向的拉伸载荷的方向拉伸和排列。最后，对本研究的实验结果和文献中的相关测试结果进行了深入解读。该数值模型与拉伸应变下观察到的孔径特征的实际变化非常吻合。