Experimental Study for the Embedded Depth of Support Structure Foundation Pit in Granite Residual Soil Area

Table 1

The information of soil used.

Stratum		Average thickness (m)	Lithology characteristics
Period	Epoch
Quaternary period	Holocene (Q4^ml)	6.3	It comprises the tawny clay and brown maroon sand with the coarse side and hardpan strata. And, it is slightly wet, mostly slightly dense state, locally loose state, or moderately dense.
	Holocene (Q4^mc)	3.0	It mainly comprises the cinereous clay with a small amount of organic matter. The cut surface is smooth with a slight gloss. And, it contains the gravel with lens shape once in a while.
	Pleistocene (Q3^al + pl)	1.7	The primary color is tawny, and the brown maroon color, greyish color, etc., are partly distributed on it. And, it mainly comprises sandy clay, clayey sand gravel, and clayey sand.
	Pleistocene (Q3^el)	11.2	The color is greyish and brown. The weathered host rock is mainly medium-coarse-grained granite, the structure of the host rock is clearly visible, gravel sand accounts for about 25%, and the composition is quartz.
Cretaceous	Yanshanian ()	5.1	The primary color is yellowish-brown and reddish-brown. The rock is weathered violently, and the organizational structure has been basically destroyed, but it is still recognizable. The core is in the shape of a hard soil column, which is easy to disintegrate when exposed to water.
	Yanshanian ()	14.4	The primary color is brown-yellow, gray-brown, the rock is weathered strongly, the organizational structure has been partially destroyed, and it disintegrates in water