粉煤灰-硅灰对大体积混凝土力学性能的影响  

The influence of fly ash and silica fume on the mechanical properties of mass concrete

作　　者：江厚亮 周天应 尹长权 JIANG Houliang;ZHOU Tianying;YIN Changquan(China Harbour Engineering Company Ltd.,Beijing 100010,China)

机构地区：[1]中国港湾工程有限责任公司,北京100010

出　　处：《四川建筑科学研究》2025年第2期80-85,共6页Sichuan Building Science

摘　　要：为改善大体积混凝土的抗裂性能和抗变形能力,以不同掺量的粉煤灰及粉煤灰-3.5%硅灰作为矿物掺合料提高其抗压强度和劈裂抗拉强度。结果表明:适当的粉煤灰掺量可以有效提高大体积混凝土的抗压强度和劈裂抗拉强度,然而过高的粉煤灰掺量会对强度增长带来负面影响;硅灰的加入可有效提高相同粉煤灰掺量大体积混凝土的强度;在相同粉煤灰掺量下,大体积混凝土的抗压强度约为抗拉强度的8.63~13.49倍;20%粉煤灰掺量的大体积混凝土在控制收缩变形方面表现最佳;建立了大体积混凝土的抗压强度和劈裂抗拉强度关系模型,该模型可有效预测大体积混凝土的劈裂抗拉强度并指导大体积混凝土的施工。基于微观分析揭示了粉煤灰和硅灰对大体积混凝土强度的影响机理。To improve the crack resistance and deformation resistance of mass concrete,different amounts of fly ash and fly ash-35%silica fume were used as mineral admixtures to improve its compressive strength and splitting tensile strength.The results show that an appropriate fly ash content can effectively improve the compressive strength and splitting tensile strength of mass concrete,but excessive fly ash content will have a negative impact on strength growth.The addition of silica fume can effectively improve the strength of mass concrete with the same amount of fly ash.Furthermore,the compressive strength of mass concrete under the same fly ash content is approximately 863 to 1349 times of the tensile strength.The mass concrete with a 20%fly ash content performs the best in controlling shrinkage deformation.A relationship model between the compressive strength and splitting tensile strength of mass concrete was established,which can effectively predict the splitting tensile strength of mass concrete and guide the construction of mass concrete.Based on microscopic analysis,the mechanism of strength formation of mass concrete which affected by fly ash and silica fume was revealed.

关 键 词：粉煤灰 硅灰 大体积混凝土 力学性能 关系模型 

分 类 号：TU528.041[建筑科学—建筑技术科学]