Experimental Study on Main Physical Parameters Controlling Shear Strength of Unsaturated Loess

Table 5

Quartz sand and quartz flour direct shear test results.

Water content (%)	Internal friction angle (°)	Dry density (g/cm^3)	Internal friction angle (°)
40–70 mesh quartz sand
0	37.45	1.4	35.87
5	34.98	1.5	37.45
10	33.38	1.6	40.58
15	31.2	—	—
20	30.1	—	—
400 mesh quartz flour
0	39.83	1.4	38.11
5	38.73	1.5	39.83
10	37.56	1.6	42.09
15	36.72	—	—
20	35.98	—	—