Effects of Using Pozzolan and Portland Cement in the Treatment of Dispersive Clay

Table 1

Properties of clay from Azerbaijan which has been altered to become fully dispersive.

	Standard	Value
Geotechnical properties
Sand (%)	ASTM D 422-63 [24]	2
Silt fraction (%)	ASTM D 422-63 [24]	36
Clay fraction (%)	ASTM D 422-63 [24]	62
Liquid limit (%)	ASTM D 4318-98 [25]	34
Plastic limit (%)	ASTM D 4318-98 [25]	17
Plasticity index (%)	ASTM D 4318-98 [25]	17
Soil classification	ASTM D 2487-98 [26]	CL
Specific gravity (Gs)	ASTM D 854-98 [27]	2.79
Optimum moisture content (%)	ASTM D 698-91 [28]	16.5
Maximum dry density (g/cm^3)	ASTM D 698-91 [28]	1.82
Unconfined compressive strength (kPa)	ASTM D 2166-98a [29]	320
Chemical properties
PH	ASTM D 2967-71 [30]	8.5
Na^+, (meq/lit)	ASTM D 4542-95 [15]	179.16
K^+, (meq/lit)	ASTM D 4542-95 [15]	16.89
Ca^2+, (meq/lit)	ASTM D 4542-95 [15]	21.25
Mg^2+, (meq/lit)	ASTM D 4542-95 [15]	13.15
EC (Electrical conductivity), (ms/cm)	—	20.9
TDS (Total dissolved salts: Na^+ + Ca^2+ + Mg^2+ + K^+), (meq/lit)	—	230.45
SAR (Sodium absorption ratio), (meq/lit)	—	43.2
PS (Percent sodium over total dissolved salts)	—	78
Dispersivity properties
Percent dispersion by double hydrometer test	ASTM D 4221-99 [13]	100
Call name		Fully dispersive clay
Classification by double hydrometer test	ASTM D 4221-99 [13]	Dispersive
Classification by pinhole test	ASTM D 4647-93 [14]	Dispersive (D1)
Classification by chemical test	Sherard et al., 1976 [16]	Dispersive