Geotechnical Function – EQUIS.GEOTECH_UNCONF_COMP

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Geotechnical Function – EQUIS.GEOTECH_UNCONF_COMP



The EQUIS.GEOTECH_UNCONF_COMP function queries Unconfined Compression (UC) test details from the DT_GEO_RESULT and DT_GEO_TEST_PARAMETER tables where DT_GEO_TEST.TEST_TYPE = ‘Unconf_Compression’. Based on the parameters present, the function calculates other result values. The data produced by the EQUIS.GEOTECH_UNCONF_COMP function is used in the Geotechnical Unconfined Compression report.


Function Details


The function dynamically grabs data based on the data present in the database. If a user has entered the strength, failure strain, or strain rate results of a UC test into DT_GEO_RESULT.GEO_RESULT_CODE = ‘strength’, ‘failure_strain_val’, or ‘strain_rate’ (where DT_GEO_TEST.TEST_TYPE = 'Unconf_Compression’), then the function will report these results directly from the database. If these values are not directly entered into the database, then the function will use the available data to calculate these results.


The function also queries multiple parameters from the DT_GEO_RESULT table with GEO_RESULT_CODE = ‘water_content’, ‘dry_density’, ‘wet_density’, ‘strain rate’, ‘specific_gravity’, etc. Based on the presence of these parameters, the function will calculate and report the saturation, void ratio, height diameter ratio, and undrained shear strength.


The function reports the Strength result in the unit specified in DT_TASK_PARAMETER.PARAM_CODE = ‘comp_strength_units’. The function supports the following units:

pounds per square foot (PSF),

pounds per square inch (PSI),

tons per square foot (TSF), and

megapascals (MPa).


If there are multiple tasks in a facility, the function will check the DT_TASK_PARAMETER.PARAM_CODE = ‘comp_strength_units’ associated with the source sample’s task.



Function Outputs – UC Test Parameters


The following table lists the UC test parameters that the EQUIS.GEOTECH_UNCONF_COMP function outputs, including function field name, associated unit, and equation used (when applicable).



Field Name


Equation (if applicable)

Strain at Failure



Strain value associated with the maximum stress value

Unconfined Compressive Strength, qu



Maximum Stress from test readings

Saturation, S



wc = Water Content

e = Void Ratio

Void Ratio, e



Undrained Shear Strength, Su



Height-Diameter Ratio





This function also returns the appropriate image file to display in the Geotechnical Unconfined Compression report. The function will search for an associated image in the following order:

1.If a failure image was uploaded with a specific sample, then the function searches for this image in the DT_FILE table where:


b.DT_FILE.PLACE_CODE = sys_sample_code

c.DT_FILE.FACILITY_ID = task_code

2.If a sample image was not included, the function will query a generic image from the DT_FILE table based on the DT_GEO_RESULT.GEO_RESULT_CODE = ‘failure_mode’ defined for the sample. The function searches for the appropriate image where:


b.DT_FILE.PLACE_CODE = failure mode


The supported types of failure mode are “BULGE” and “SHEAR”. If the RESULT_VALUE_TEXT associated with  DT_GEO_RESULT.GEO_RESULT_CODE = ‘failure_mode’ does not equal “BULGE” or “SHEAR”, then the function returns the image from the DT_FILE table associated with DT_FILE.PLACE_CODE = ‘NULL’.