什么叫做混凝土的二次振捣?这就是在混凝土的坍落度已经消失,但接近初凝时,再次重新振捣混凝土,这就叫做二次振捣。只要振捣棒能够插入到混凝土中去,而混凝土仍然可变为塑性,不致于在混凝土中留下振捣棒的孔穴时,就可以进行二次振捣。二次振捣的时间可掌握在混凝土浇灌后1～4个小时为宜,确切时间要根据 What is called the second vibration of concrete? This is when the slump of the concrete has disappeared, but near the initial setting, the concrete is re-vibrated again, which is called the second vibration. As long as the vibrator rod can be inserted into the concrete and the concrete can still become plastic, and the vibrator rod hole is not left in the concrete, the second vibrating can be performed. The time for the second vibrator can be controlled by 1~4 hours after the concrete is poured. The exact time should be based on