摘  要：针对贵州地区公路工程桥梁用高性能混凝土机制砂石粉含量高、粉煤灰质量差等问题，对不同石粉含量、不同矿物掺合料的机制砂混凝土性能进行了试验研究。研究结果表明，石粉虽作为惰性材料，但在一定掺量范围内，对混凝土性能具有一定程度的改善。在实际工程中，建议石粉含量控制在10%左右；Ⅱ级粉煤灰因其烧失量大、活性小对混凝土性能有着不利的影响；磨细复合掺合料可显著提升机制砂混凝土工作性能、力学性能以及耐久性能。因此，针对贵州地区优质粉煤灰匮乏的现状，建议将低等级粉煤灰与磨细矿渣进行二次加工磨细后再掺入混凝土使用。此外，根据研究成果在工程中的应用情况，提出了贵州地区桥梁用机制砂混凝土原材料的选型标准。

Abstract: According to the problems of manufactured sand high performance concrete in highway bridge project in Guizhou area, such as high content of sand powder and poor quality of fly ash, the study of manufactured sand concrete with different mineral admixtures and sand powder is carried out. The results show that although the powder is the inert material, but concrete properties can be improved in a certain dosage range. Recommended powder content is controlled at about 10%. Because of large burning loss and low activity, Ⅱ grade fly ash has a negative effect on the performance of concrete. Ground composite admixture can significantly improve the performance of manufactured sand concrete. Therefore, in view of the present situation of lack of high quality fly ash in Guizhou area, it is suggested that using low grade fly ash and slag to fine grind again. Based on the application of research results in engineering, selection criteria of raw materials for the construction of bridges in Guizhou area is put forward.