Calculation of Subgrade Moisture Index in Seasonally Frozen Regions considering Evapotranspiration at Subzero Temperatures and the Pavement Coverage Effect

Table 4

Moisture balance calculation data.

Month	Pi (cm)	PEi (cm)	∆mi (cm)	Si (cm)/di (cm)	Ri (cm)	DFi (cm)
1	0.37	1.37	−1.00	20.60	0	0
2	0.52	2.21	−1.69	18.91	0	0
3	0.83	4.97	−4.14	14.77	0	0
4	2.52	8.55	−6.03	8.74	0	0
5	5.40	11.76	−6.36	2.38	0	0
6	8.88	10.91	−2.03	0.36	0	0
7	11.53	11.44	0.09	0.44	0	0
8	12.19	10.25	1.94	2.38	0	0
9	6.41	7.03	−0.62	1.76	0	0
10	2.46	6.36	−3.90	−2.14	0	2.14
11	1.08	2.44	−1.36	−3.50	0	3.50
12	0.64	1.40	−0.76	−4.26	0	4.26
Total	—	78.69	—	—	0	9.90
	−7.55
S0 = θ0h = 0.18 × 120 = 21.6 cm; Smax = 0.24 × 120 = 28.8 cm