钢壳沉管自密实混凝土浇筑顶面缺陷表征研究

Characterization of top surface defects of steel shell immersed tube self-compacting concrete

以深中通道钢壳沉管自密实混凝土浇筑为研究背景,通过单仓缩尺模型试验验证了自密实混凝土配合比的工作性,掌握了混凝土浇筑时缺陷产生的位置和原因,并采用图像二灰度处理法和石粉填充法测试了混凝土浇筑顶面的缺陷面积占比、体积占比、最大/平均缺陷深度、主要缺陷分布等参数,较大缺陷往往集中出现在下料口附近、顶面加劲肋背面,为钢壳沉管自密实混凝土的后续施工提供了数据支撑。

Taking the self-compacting concrete pouring of steel shell immersed tubes in Shenzhen-Zhongshan Channel as the research background,the workability of the self-compacting concrete mix ratio was verified by the single-bin scale model test,and the location and cause of the defects during the concrete pouring were grasped.The ratio of defect area and volume,the maximum/average defect depth,the main defect distribution and other parameters of the top surface of the concrete pouring were tested by using two-level grayscale processing method and the stone powder filling method,the larger defects are often concentrated near the blanking opening and the back of the top stiffener,which provides data support for the subsequent construction of the steel shell immersed tube self-compacting concrete.