不同粉煤灰掺量的水泥浆体的特性研究

Study on the Properties of Cement Paste with Different Fly Ash Contents

道路的设计与建造材料中含有可循环材料是可持续发展的潜在需求。在本研究中,依托过境改线工程,通过添加不同比例(0,20%,40%,60和80%)的粉煤灰(Fly ash, FA)制备粉煤灰水泥浆,用以替代普通水泥。检测不同粉煤灰掺入比例的水泥的干密度、抗压强度、吸水性、干缩率以及氯离子渗透等参数性能。根据检测结果,粉煤灰占比20%的粉煤灰水泥浆体可以在所有养护年龄(固化年龄)下获得与参考配比相当的承载能力。含有20%粉煤灰的试样在120天时展现出了70.9MPa的最大抗压强度,而含80%粉煤灰的水泥样品的承载能力最弱,抗压强度为39.3MPa。干密度与吸水性的相关测试结果与抗压强度的测试结果一致,因此,通过将粉煤灰的掺入比控制在20%以下可以获得最优的工程特性。通过将高比例粉煤灰替代普通水泥有助于提高粉煤灰水泥浆体的干缩。在粉煤灰水泥浆体中优化粉煤灰含量低于20%,有利于促进生态增长目标的同时,保持可接受的性能,凸显了合理利用粉煤灰在实现生态考虑和期望的工程特性之间达成平衡的积极影响。

The inclusion of recyclable materials in motorways design and construction materials is a potential requirement for sustainable development.In this study,relying on the bypass realignment project,fly ash cement paste was prepared by adding different proportions(0,20%,40%,60%,and 80%)of fly ash(FA)to replace ordinary cement.The dry density,compressive strength,water absorption,drying shrinkage,and chloride ion penetration of cement with different fly ash incorporation ratios were tested.According to the test results,fly ash cement paste with 20%fly ash can achieve comparable load-bearing capacity to the reference mixture at all curing ages.The sample containing 20%fly ash showed the maximum compressive strength of 70.9MPa at 120 days,while the load-bearing capacity of the cement sample with 80%fly ash was the weakest,with a compressive strength of 39.3MPa.The results of dry density and water absorption tests were consistent with the compressive strength test results.Therefore,the best engineering properties can be obtained by controlling the fly ash incorporation ratio below 20%.Replacing ordinary cement with a high proportion of fly ash helps to improve the drying shrinkage of fly ash cement paste.Overall,optimizing the fly ash content below 20%in fly ash cement paste is beneficial for promoting ecological growth goals while maintaining acceptable performance,highlighting the positive impact of reasonable fly ash utilization in balancing ecological considerations and desired engineering properties.