Integrating field and laboratory data into geotechnical models: A cornerstone for reliable analysis

In geotechnical projects, building reliable models requires more than theoretical knowledge and sophisticated software; it essentially depends on the quality of the data used. Consistent integration between field and laboratory data ensures that models faithfully represent the actual behavior of the soils and rocks under study.

Importance of Field Trials

Therefore, field tests, such as SPT, CPTu, DMT, PMT, and Vane Test, are essential for capturing the in-situ conditions of materials. They provide important parameters such as undrained strength, load capacity, and stiffness, in addition to identifying the presence of critical layers, such as collapsible, expansive, or liquefaction-prone soils.

Role of Laboratory Tests

Laboratory tests, such as compaction, permeability, direct shear, triaxial shear, consolidation, and Atterberg limits, allow for more accurate assessment of the physical and mechanical properties of materials. These data are obtained under controlled conditions, enabling refined model calibration.

Representativeness and Reliability of Models

Therefore, models based on inconsistent data or excessive generalizations tend to mask critical problems, compromising design decisions and structural safety. Therefore, the reliability of a geotechnical model is directly linked to the representativeness of the data. To achieve this, it is essential to:

• Properly characterize the materials, considering lateral and vertical variations.
  
• Correlate field and laboratory data, ensuring consistency between results.
  
• Use parameters compatible with the type of analysis (static, dynamic, undrained, drained, etc.).
  
• Adopt statistical and geotechnical criteria in the selection of characteristic parameters (e.g., representative values such as averages, conservative minimums or percentiles).
  

Best Practices for Reliable Models

To ensure this reliability, the following best practices are typically adopted when building models:

1. Multidisciplinary Integration: Geologists, field engineers and designers must work together from the investigation phase onwards.
   
2. Investigation Planning: The survey mesh and the number of tests must be sized according to the type of structure and the level of reliability required.
   
3. Cross-Validation: Comparisons between different methods (e.g., SPT vs. CPTu or triaxial testing vs. direct shear) are critical to identify discrepancies and validate trends.
   
4. Continuous Update: The geotechnical model must be reviewed and adjusted as excavations, instrumentation and performance feedback are progressed.
   

Therefore, building robust geotechnical models requires a balance of field practice, laboratory rigor, and engineering judgment. The real difference lies in the ability to transform raw data into reliable information for decision-making.

In the VinQ, we believe that the success of any enterprise depends, above all, on a solid technical base of knowledge.