钢壳沉管自密实混凝土质量控制研究

Quality control for steel-shell submerged tunnel used self-compacting concrete

针对钢壳沉管自密实混凝土质量控制问题,调研了国外类似工程指标情况,结合自密实混凝土综合分析相关标准规范和实际可操作性,初步提出了钢壳沉管自密实混凝土质量控制指标。开展了室内试验和现场模型试验,验证并优化了混凝土质量控制指标,明确了排气设计、浇筑工艺等关键质量控制参数。采用所提出的质量控制方法,可有效保证C50等级自密实混凝土的流动性、填充性和抗离析性,实现混凝土在管节舱室内的自动填充并形成密实结构。

For the quality control problems of steel-shell submerged tunnel used self-compacting concrete（SCC）, we carried out index surveys of similar projects in foreign countries, put forward the initial quality control indexes of the SCC followed by a systematic analysis concerning the operability and requirements in relative specifications. We carried out indoor and model experiments to verify and optimize the concrete quality control indexes, and defined the key quality control parameters such as exhaust design and placing technology. The summarized quality control method can effectively guarantee the fluidity, filling ability and segregation resistance of the SCC with strength of C50, and realize the automatic filling and forming of dense structure of concrete in the tube cabin.