Research And Application Of Formwork For Bidirectional Inclined In National Stadium

The bidirectional inclined columns in National Stadium apply a compositive function of pressure and torque on frameworks and the support system. The strength is rather complicated and the support mounting is also very difficult. In addition, the bidirectional inclined columns in this project are various in specs and large in amount. The quality should meet the fair-faced-concrete standard. It also requires advanced construction technology and arrangement as well as high construction safety rate and technical economy index. Since such form as bidirectional inclined columns is special and seldom applied in previous engineering construction, we need not only to integrate the proven engineering experience but to innovate in technology with accordance to the new engineering conditions during the research, design and application of the framework and support.I divided the topic of Framework & Support for Bidirectional Inclined Columns in National Stadium Project into ten key technologies: 1) fair-faced-concrete column framework; 2) special framework for bidirectional inclined columns; 3) special framework for Y-shape columns; 4) 3-D design technology; 5) construction flow arrangement technology for framework; 6) super-high columns & multi-span columns support technology; 7) standard-floor inclined columns support technology;8) edged-columns support technology;9) intersected-columns construction technology; 10) finite element technology application. I led all the research work for this topic and mainly completed the research on 1~4 & 6~9 technologies.What I have accomplished in this topic research is focused on: construction plan design and testing research on bidirectional inclined framework and support, engineering design and research on flatted steel-wood fair-faced-concrete column framework, design for bidirectional inclined special-framework, technical research on 3D support used for bidirectional inclined framework, design for 3D fastener-style steel pipe support system used for engineering construction, and construction engineering research on bidirectional inclined framework. These accomplishments can be summarized into three unique features: innovative in the design of standard framework structure & node of fair-faced concrete column framework system; breakthrough in concept– 3D support model plan skillfully addressed a solution to the compositive function of pressure and torque on bidirectional inclined columns, which can not be successfully resolved by traditional single-side support plan using simplified plane model; advanced in technology– inclined-column special framework and 3D support design overcame the difficulty in dimensional positioning and precision controlling of dimensional special component construction.What I have achieved in the research of framework for bidirectional inclined fair-faced-concrete columns is successfully applied in the National Stadium Project. In practice, I successfully resolved the technical issues regarding bidirectional inclined column framework construction and achieved the target of'Ten New Technologies of Ministry of Construction and Beijing Deployment & Application Project'and'Five Unification of Safety, Quality, Schedule, Function & Benefit'set for this project. Moreover, the research results provide technical instruction and valuable experience for the construction of fair-faced concrete project and dimensional special component project. Finally, the innovative model I created in the research of engineering technical problems also provides a guide for the development of domestic construction technology.