基于DIP的天然砂与机制砂粒形评价方法

A Particle Shape Evaluation Method for Natural Sand and Manufactured Sand Based on DIP

摘要:

针对北京地区天然砂与机制砂，应用数字图像处理（DIP）技术评估这2种细骨料的粒形特征，并据此建立了综合评价指数。结果表明：天然砂在5项粒形参数上均优于机制砂，其中内切圆度差异最为显著；以质量比4∶6复配天然砂与机制砂所制备的砂浆，在工作性能和力学性能方面均表现出最佳效果，砂浆保水性佳，分层度仅为8 mm，28 d 抗压强度和抗折强度分别达到25.1、6.6 MPa；合理的复配比例有效利用了机制砂的“次骨架”效应，以及天然砂的粒形、填充优势，显著优化了砂浆的整体性能。

Abstract:

The particle shape characteristics of natural sand and manufactured sand in the Beijing area were evaluated using digital image processing （DIP） technology， and a comprehensive evaluation index was established accordingly. The results indicate that natural sand outperforms manufactured sand in all five particle shape parameters， with the most significant difference observed in circularity. Mortar prepared with a 4∶6 mass ratio of natural sand to manufactured sand exhibits optimal performance in both workability and mechanical properties. The mortar demonstrates good water retention， a segregation degree of only 8 mm， a 28 d compressive strength of 25.1 MPa， and a flexural strength of 6.6 MPa. The reasonable blending ratio is effectively utilized with the secondary skeleton effect of manufactured sand and the shape and packing advantages of natural sand， thus the overall performance of the mortar is significantly enhanced.