Study on Variation of Surface Runoff and Soil Moisture Content in the Subgrade of Permeable Pavement Structure

Table 4

Surface runoff coefficients at different rainfall intensities.

Thickness of base layer (cm)	Rainfall intensity (5.5 mm/min)			Rainfall intensity (4.6 mm/min)			Rainfall intensity (3.4 mm/min)			Rainfall intensity (2.5 mm/min)
	Total rainfall (mm)	Surface runoff (mm)	Surface runoff coefficient (%)	Total rainfall (mm)	Surface runoff (mm)	Surface runoff coefficient (%)	Total rainfall (mm)	Surface runoff (mm)	Surface runoff coefficient (%)	Total rainfall (mm)	Surface runoff (mm)	Surface runoff coefficient (%)
30	660	33	5	552	5	1	408	0	0	300	0	0
25	660	85	13	552	44	8	408	0	0	300	0	0
20	660	132	20	552	77	14	408	16	4	300	0	0
15	660	171	26	552	104	19	408	29	7	300	0	0