土工织物的孔径是反映其渗滤性能的重要参数，然而该参数的测定方法目前尚未标准化，各种测定方法所测得的结果不尽相同。为此比较和分析了现有的几种测定方法，并将图像分析法和数学模型法相结合，提出了反滤材料选择的新思路。

The opening size of geotextile is an important filtration parameter, but its measuring methods aren't standardization so far. Different approaches give different results. Several kinds of existing testing methods are compared and analyzed. Then by integrating image analysis method with mathematical model method, a new idea for choosing filter material is brought out.