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Fields for table: SUBGRADE_LAYER_PROP

Field NameCodesData TypeUnitsTest ProtocolDescription
STATE_CODE
STATE_PROVINCENUMBER(2)


Numerical code for state or province. U.S. codes are consistent with Federal Information Processing Standards.
LIQUID_LIMIT

NUMBER(2)
%

Average of the liquid limits measured.
MAXIMUM_LAB_DRY_DENSITY

NUMBER(3)
psf

Maximum laboratory dry density.
OPTIMUM_LAB_MOISTURE_CONTENT

NUMBER(3,1)
%

Optimum moisture content of subgrade.
MAX_LAB_DRY_DENSITY_TEST
MAX_LAB_DRY_DENSITY_TESTVARCHAR2(1)


Code indicating the AASHTO test method used to determine the maximum dry density.
MAX_LAB_DRY_DENSITY_TEST_OTHER

VARCHAR2(40)


The AASHTO test method used to determine the maximum dry density if other than those specified
COMPACTIVE_ENERGY_OTHER

NUMBER(3,1)
ft-lbs/cu in

Compactive energy applied if test method was not standard AASHTO or modified AASHTO.
IN_SITU_DRY_DEN_MEAN

NUMBER(3)
%

Average in situ dry density as a percent of the maximum.
IN_SITU_DRY_DEN_MAX

NUMBER(3)
%

Maximum in situ dry density as a percent of the maximum.
IN_SITU_DRY_DEN_MIN

NUMBER(3)
%

Minimum in situ dry density as a percent of the maximum.
NO_SAMP_IN_SITU_DRY_DEN

NUMBER(3)


Number of measurements taken for in situ dry density as a percent of the maximum.
SHRP_ID

VARCHAR2(4)


Test section identification number assigned by LTPP program. Must be combined with STATE_CODE to be unique.
IN_SITU_DRY_DEN_STD_DEV

NUMBER(3)
%

Standard deviation of the in situ dry density as a percent of the maximum.
IN_SITU_MOISTURE_OPT_MEAN

NUMBER(4,1)
%

Average in situ moisture content as a percent of the optimum.
IN_SITU_MOISTURE_OPT_MIN

NUMBER(4,1)
%

Minimum in situ moisture content as a percent of the optimum.
IN_SITU_MOISTURE_OPT_MAX

NUMBER(4,1)
%

Maximum in situ moisture content as a percent of the optimum.
NO_SAMP_IN_SITU_MOISTURE_OPT

NUMBER(3)


Number of measurements taken for in situ moisture content as a percent of the optimum.
IN_SITU_MOISTURE_OPT_STD_DEV

NUMBER(5,2)
%

Standard deviation of the in situ moisture content as a percent of the optimum.
IN_SITU_DRY_DEN_PCF_MEAN

NUMBER(3)
pcf

Average in situ dry density.
IN_SITU_DRY_DEN_PCF_MIN

NUMBER(3)
pcf

Minimum in situ dry density.
IN_SITU_DRY_DEN_PCF_MAX

NUMBER(3)
pcf

Maximum in situ dry density.
NO_SAMP_IN_SITU_DRY_DEN_PCF

NUMBER(3)


Number of measurements taken for in situ dry density.
LAYER_NO

NUMBER(2)


Unique sequential number assigned to pavement layers, starting with layer 1 as the deepest layer (subgrade).
IN_SITU_DRY_DEN_PCF_STD_DEV

NUMBER(3)
pcf

Standard deviation of measured in situ dry density.
IN_SITU_MOISTURE_DW_MEAN

NUMBER(3,1)
%

Average in situ moisture content as a percent of dry weight.
IN_SITU_MOISTURE_DW_MIN

NUMBER(3,1)
%

Minimum in situ moisture content as a percent of dry weight.
IN_SITU_MOISTURE_DW_MAX

NUMBER(3,1)
%

Maximum in situ moisture content as a percent of dry weight.
NO_SAMP_IN_SITU_MOISTURE_DW

NUMBER(3)


Number of measurements taken for in situ moisture content as a percent of dry weight.
IN_SITU_MOISTURE_DW_STD_DEV

NUMBER(4,2)
%

Standard deviation of in situ moisture content as a percent of dry weight.
LAB_DENSITY_MIN

NUMBER(4,1)
pcf

Minimum density as determined by test method ASTM D2049.
LAB_DENSITY_MAX

NUMBER(4,1)
pcf

Maximum density as determined by test method ASTM D2049.
RELATIVE_DENSITY_MEAN

NUMBER(4,1)
%

Mean relative density.
RELATIVE_DENSITY_MIN

NUMBER(4,1)
%

Minimum relative density.
AASHTO_SOIL_CLASS
AASHTO_SOIL_CLASSVARCHAR2(2)


Code for AASHTO soil classification for subgrade material.
NO_RELATIVE_DENSITY_TESTS

NUMBER(3)


Number of relative density tests performed.
RELATIVE_DENSITY_MAX

NUMBER(4,1)
%

Maximum relative density.
RELATIVE_DENSITY_STD_DEV

NUMBER(3,1)
%

Standard deviation relative density.
SOIL_SUCTION

NUMBER(4,1)
tons/sq ft

Value for soil suction.
EXPANSION_INDEX

NUMBER(3)


Expansion index as determined by ASTM "test method for expansion index of soils".
SWELL_PRESSURE_VALUE

NUMBER(3)
psi

Swell pressure.
SWELL_PRESSURE_CODE

VARCHAR2(1)


Code indicating what swell pressure test was used.
SWELL_PRESSURE_CODE_OTHER
SWELL_PRESSURE_TESTVARCHAR2(40)


Swell pressure test used if other than those specified.
PERCENT_FINER_02

NUMBER(3,1)
%

Percent material finer than .02 mm.
AVG_RATE_HEAVE

NUMBER(3,1)
mm/day

Average rate of heave during freezing test.
CALIFORNIA_BEARING_RATIO

NUMBER(3)
%

Mean California bearing ratio.
FROST_SUSCEPTIBILITY_CODE
FROST_SUSCEPTIBILITY_CODEVARCHAR2(1)


Code indicating frost susceptibility classification.
RECORD_STATUS

VARCHAR2(1)


A code indicating the general quality of the data.
RESISTANCE

NUMBER(3)
%

Mean resistance (r-value).
SUBGRADE_REACTION_MODULUS

NUMBER(3)
pci

Modulus of subgrade reaction (k-value).
TEST_TYPE
TEST_TYPEVARCHAR2(1)


Code indicating what type of k-value test was used.
PLASTICITY_INDEX

NUMBER(2)
%

Plasticity index.