Research on Shear Strength Parameters of the Silty Fine Sand and the Rounded Gravel Layers in Nanning City

Table 4

Strength parameters of the silty fine sand reported in the current regulations.

Source	Soil type	Relevant indexes		Shear stress index
				c (kPa)	φ (°)
Code for foundation pit support in Hubei Province	Silty and fine sand	Standard penetration test blow count	10	0	27
			14	0	30
			21	0	33
			30	0	35
			40	0	36
Code for foundation pit support in Guangdong Province	Fine sand	Compactness	Loose	–	25–28.5
			Slightly dense	–	29–32
Rock and soil engineering	Fine sand	Compactness	Loose	–	28
			Slightly dense	–	30
			Moderately dense	–	34
			Dense	–	36
	Silty sand	Compactness	Loose	–	26
			Slightly dense	–	28
			Moderately dense	–	32
			Dense	–	34
	Ultrafine sandy soil	Compactness	Moderately dense	–	28–32
			Dense	–	30–34
Geological manual for water conservancy and hydropower engineering	Fine sand, ultrafine sand	Standard penetration test blow count	4	–	20
			5	–	22
			6	–	24
			7	–	26
			8	–	28
	Fine sand, ultrafine sand	Void ratio	0.8	–	26
			0.7	–	28
			0.6	–	32
			0.5	–	34