聚丙烯纤维在杭州湾大桥海工混凝土中的应用

摘要

海工混凝土内部结构密实,具有强度高、抗氯离子渗透能力强和耐久性好等特点.但早期抗拉强度不高,甚至比同龄期普通混凝土强度低.在斜拉桥主塔结构应力易集中的变异截面或结构突变处容易产生裂缝,影响工程结构的耐久性.结合杭州湾大桥施工实践,对施工配合比设计进行大胆尝试,在海工混凝土配比中掺加了聚丙烯纤维,既实现了海工混凝土裂缝控制的目标,又达到了海工混凝土耐久性要求.%Marine concrete internal structure is dense, so it had high strength and resistance to chloride ion penetration ability, and good durability. Rut the early tensile strength is not high, even lower than normal concrete strength. Structural stress is easy to focus on the variation of cross section or structural mutations in the Cable-stayed bridge. The structure is prone to crack, thus affecting the durability of the project. This paper in combination with the construction practice of the Hangzhou Bay Bridge, the concrete construction mix with the design of a bold attempt,the marine concrete mixed with the polypropylene fiber was first time in the domestic,not only to achieve the goal of marine concrete crack control,but also to achieve the durability of marine concrete requirements.