大型地下高速铁路车站轨顶风道自密实混凝土施工技术

Construction Technology of Self-compacting Concrete of Wind Duct on Track Top of Large-scale Underground Station on High-speed Railway

通过广深港客运专线福田车站轨顶风道采用自密实混凝土的施工实例,详细介绍采用自密实混凝土的必要性、优越性及性能指标选择、施工控制措施等自密实混凝土施工的全过程。重点阐述自密性混凝土在密集钢筋、狭小结构内的使用技术,包括原材料、配合比设计及优化、支架设计及检算和混凝土生产、运输、浇筑和养护过程控制等方面,介绍自密实混凝土施工的技术要领,解决了轨顶风道采用传统混凝土施工中漏振、过振及钢筋密集难以振捣的问题,为同类工程提供借鉴。

By the case study of self-compacting concrete which was used for track-top wind duct of the Futian Station on the Guangzhou-Shenzhen-Hongkong Passenger Dedicated Line, this paper introduced in detail the necessity, the advantage, the whole performance index selection process and the construction control measures about self-compacting concrete. Moreover, the application technology of self-compacting concrete under the condition of dense steel-bar and narrow structure were described emphatically, including raw materials, mix proportion design and optimization, bracket design and check calculation, also including self-compacting concrete production, transportation, pouring, curing process and other key technical issues. As a result, these technologies have solved the problems in the construction process of track-top wind duct by traditional concrete method, in relation to the missed vibration, the excessive vibration and the difficult vibration because of the dense steel-bar, providing reference for similar project as well.