Development of a New Type of Alkali-Free Liquid Accelerator for Wet Shotcrete in Coal Mine and Its Engineering Application

Table 4

Effect of vibration frequency on setting time under the same test conditions.

Accelerator mass content/%	Vibration frequency	Initial setting time/min	Final setting time/min	Test error/s
6	0	4.8	7.0	>10
	3	3.4	7.3	<10
	5	3.3	7.7	<5
	10	3.5	8.3	<5
	20	4.0	10.0	<5
	30	4.4	12.5	<5