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AGS4 Reference

AGS4 is a standardized text file format specifically designed for exchanging geotechnical information between different software systems used in geotechnical engineering. It organizes borehole logs, laboratory test results, and field measurements into structured data tables with validation rules to ensure consistent data quality across the geotechnical industry.

In the AGS4 format, Groups are organizational containers that structure geotechnical data. Each Group represents a specific aspect of geotechnical investigation, for example, project information (PROJ), location details (LOCA), sample information (SAMP), or specific test types like Standard Penetration Tests (ISPT).

AGS4 Groups are organised in a hierarchical manner. Each sample (SAMP) belongs to a location (LOCA). Each location belongs to a project (PROJ).

Here’s a visual of the hierarchy of groups commonly found in an AGS4 file.

PROJ Project information LOCA Location details ABBR Abbreviation Definitions TRAN Data File Transmission Information / Data Status TYPE Definition of Data Types UNIT Definition of Units SAMP Sample information IPRG In Situ permeability GEOL Geological descriptions BKFL Backfill details ISPT Standard Penetration Test GRAG Particle size distribution analysis LNMC Water content IPRT In Situ permeability data GRAT Particle size distribution analysis data

All Groups Hierarchy Tree

While AGS defines a load of groups, not all of them are used in every project. For reference, here is the full hierarchy tree of all groups.

AGS4 file PROJ Project Information ABBR Abbreviation Definitions DICT User Defined Groups and Headings FILE Associated Files TRAN Data File Transmission Information / Data Status TYPE Definition of Data Types UNIT Definition of Units LOCA Location Details SAMP Sample Information BKFL Exploratory Hole Backfill Details CDIA Casing Diameter by Depth CHIS Chiselling Details CORE Coring Information DCPG Dynamic Cone Penetrometer Tests - General DETL Stratum Detail Descriptions DISC Discontinuity Data DLOG Driller Geological Description DOBS Drilling/Advancement Observations & Parameters DPRG Dynamic Probe Tests - General DREM Depth Related Remarks FGHG Field Geohydraulic Testing - General FLSH Drilling Flush Details FRAC Fracture Spacing GEOL Field Geological Descriptions HDIA Hole Diameter by Depth HDPH Depth Related Exploratory Hole Information HORN Exploratory Hole Orientation and Inclination ICBR In Situ California Bearing Ratio Tests IDEN In Situ Density Tests IFID On Site Volatile Headspace Testing Using Flame Ionisation Detector IPEN In Situ Hand Penetrometer Tests IPID On Site Volatile Headspace Testing by Photo Ionisation Detector IPRG In Situ Permeability Tests - General IRDX In Situ Redox Tests IRES In Situ Resistivity Tests ISAG Soakaway Tests - General ISPT Standard Penetration Test Results IVAN In Situ Vane Tests AAVT Aggregate Abrasion Tests ACVT Aggregate Crushing Value Tests AELO Aggregate Elongation Index Tests AFLK Aggregate Flakiness Tests AIVT Aggregate Impact Value Tests ALOS Los Angeles Abrasion Tests APSV Aggregate Polished Stone Tests ARTW Aggregate Determination of the Resistance to Wear (micro-Deval) ASDI Slake Durability Index Tests ASNS Aggregate Soundness Tests AWAD Aggregate Water Absorption Tests CBRG California Bearing Ratio Tests - General CHOC Chain of Custody Information CMPG Compaction Tests - General CONG Consolidation Tests - General CTRG Cyclic Triaxial Test - General ECTN Sample Container Details ELRG Environmental Laboratory Reporting ERES Environmental Contaminant Testing ESCG Effective Stress Consolidation Tests - General FRST Frost Susceptibility Tests GCHM Geotechnical Chemistry Testing GRAG Particle Size Distribution Analysis - General DCPT Dynamic Cone Penetrometer Tests - Data DPRB Dynamic Probe Tests - Data FGHI Field Geohydraulic Testing - Instrumentation Details FGHS Field Geohydraulic Testing - Test Results (per stage) IPRT In Situ Permeability Tests - Data ISAT Soakaway Tests - Data CBRT California Bearing Ratio Tests - Data CMPT Compaction Tests - Data CONS Consolidation Tests - Data CTRC Cyclic Triaxial Tests - Consolidation CTRS Cyclic Triaxial Test - Saturation ESCT Effective Stress Consolidation Tests - Data GRAT Particle Size Distribution Analysis - Data FGHT Field Geohydraulic Testing - Data CTRP Cyclic Triaxial Test - Derived Parameters CTRD Cyclic Triaxial Tests - Data

Headings are the specific data fields (i.e. the columns) within each group that define individual data items. Each heading represents a specific piece of information that can be recorded during geotechnical investigations, such as sample depth, moisture content, or test result values

Headings follow a standardized naming pattern, typically beginning with the group name as a prefix (e.g., “PROJ_ID” for project identifier in the PROJ group). Some headings are marked as required (*R or R), indicating that they must be populated in a valid AGS file to maintain data integrity. Headings include additional information like units of measurement, descriptions, and example values to help users understand their purpose.

Heading details
Data Definition
Each heading represents a specific piece of information that can be recorded during geotechnical investigations, such as sample depth, moisture content, or test result values.
Naming Convention
Headings follow a standardized naming pattern, typically beginning with the group name as a prefix (e.g., "PROJ_ID" for project identifier in the PROJ group).
Data Typing
Each heading has a defined data type (e.g., "ID" for identifiers, "X" for text, "N" for numeric values) that specifies what kind of information it contains.
Required Status
Some headings are marked as required (*R or R), indicating that they must be populated in a valid AGS file to maintain data integrity.
Metadata Structure
Headings include additional information like units of measurement, descriptions, and example values to help users understand their purpose.