Research on Wetting-Drying Cycles’ Effect on the Physical and Mechanical Properties of Expansive Soil Improved by OTAC-KCl

Table 4

The results of shear strength parameters during cyclic wetting-drying process.

Types of soil	Shear strength under different vertical pressures (kPa)				Internal friction angle	Cohesion	Note
	50	100	150	200	/°	c/kPa
Natural soil
0th cycle	19.1	29.6	37.6	40.7	8.3	13.5	Saturated samples
2nd cycle	15.8	24.3	32.1	36.1	7.8	9.9
4th cycle	11.6	16.5	25.7	30.7	7.6	4.5
Improved soil
0th cycle	41.9	50.3	58.6	74.4	12.0	29.8
2nd cycle	36.9	43.6	49.8	65.3	10.4	26.0
4th cycle	30.4	36.4	43.2	56.1	9.5	20.6