“鸟巢”预制清水混凝土看台关键技术

Key technology of prefabrication as-castfinish concrete bleachers platforms for the "Nest"

针对"鸟巢"清水混凝土看台预制工程数量和型号变化多、非预应力和薄臂及预埋件位置精确、表观和结构质量要求高且工期紧等特点,分析了预制工程难点,归纳了要重点解决的关键技术,并从人、机、料、法和环5个方面提出了系统的解决方案。其中的关键技术为:①量化和细化了看台板结构和表观的各项质量指标,制定了完整的质量验收标准,并作为工程最终质量验收依据。②通过分析常规预制构件偏离清水效果的现象和原因,策划出了完整的解决方案,并对看台构件的生产实施预控。③在模板设计时,通过选用钢模板并采取反打成型为主和单活梆设计辅以精细化处理,保证了成品尺寸精度、细部线条质量和成型面效果。④在混凝土配合比研究中,通过优选原材、正交试验和样板检验,研制出适用于看台板的19 mm聚丙烯纤维+I级FA+新型聚羧酸盐高效减水剂的防裂混凝土,满足了新拌混凝土施工性能好、硬化混凝土早后期强度高及看台板成品色泽亮白、气泡少、碱含量低和体积稳定性高等各项性能要求。以上措施的实施,确保看台工程达到了既定的清水质量标准。"鸟巢"看台板的高质量被国内外专家和领导誉为"世界预制构件精品的精品"。

The as-castfinish concrete bleachers platforms of the＂nest＂ are large number and specifications,with thin thickness and tight schedule and high qualitative quality,and non-prestress.So,standard for acceptance of construction quality of as-castfinish concrete precast tier is laid down firstly.Assembly line method is realized by selecting appropriate and improving technological design.Concrete bleachers platforms with high quality and as-castfinish surface are made with high precision form design,and pre-control of production,combined with scientific crack-proof concrete mix design.All the concrete bleachers platforms for the ＂nest＂ are installed now,and all the visitors and experts highly appraise of them.