针对钢筋笼上浮影响桩身质量，分析上浮原因，应用上浮数学模型，结合工程先试灌首批几根桩，确定阻力系数，找出导管埋深与混凝土上返速度关系并绘出曲线，确定正常与危险区域。（１）影响钢筋笼上浮的主要因素①混凝土灌注速度。混凝土的灌注速度愈快，产生的浮力愈大；灌注 In view of the effect of reinforcement cage floating on the pile body quality, analysis of floating causes, application of floating mathematical model, combined with the project first trial irrigation of the first batch of piles, determine the drag coefficient, find out the relationship between the depth of the buried pipe and the return speed on the concrete and draw a curve, determine Normal and dangerous areas. (1) The main factors affecting the float of the cage are: 1 Concrete infusion speed. The faster the pouring speed of concrete, the greater the buoyancy produced;