Experiments on Reducing Negative Skin Friction of Piles

Table 2

Model 1.

Moisture content (%)	Vertical force (kN)	Compressive stress (kPa)	Horizontal force (kN)	Friction strength (kPa)	Friction coefficient	Average friction coefficient
21	10	47.26	3.09	14.60	0.310	0.31
	20	94.52	6.22	29.40	0.311
	30	141.78	9.34	44.14	0.311
19	10	47.26	3.32	15.69	0.332	0.35
	20	94.52	7.53	35.59	0.376
	30	141.78	9.93	46.93	0.331
17	10	47.26	4.88	23.06	0.488	0.45
	20	94.52	8.39	39.65	0.420
	30	141.78	13.49	63.75	0.450
15	10	47.26	6.75	31.90	0.675	0.64
	20	94.52	13.12	62.00	0.656
	30	141.78	17.98	84.97	0.599
13	10	47.26	6.81	32.18	0.681	0.70
	20	94.52	15.52	73.35	0.776
	30	141.78	18.91	89.37	0.630