Soil and Geology Classification

Soil and Rock Drilling - Soil and Rock Logging - Soil and Rock Strength Testing

Soil Classification

Soil is classified into one of three major groups:

  • Coarse-grained soils (e.g. sands and gravels)
  • Fine-grained soils (e.g. silts and clays);
  • Highly organic soils (referred to as "peat")

Different classes of soil have different engineering properties. For example, sandy soils will absorb water rapidly compared to a clay soil. Almost all soils are a mixture of these three classes. Soils vary considerably based on the rock they have weathered from, their age, chemical makeup, the topography and even the surrounding vegetation.

Comprehensive soil classification systems are designed to allow a transition from field observations to basic predictions of soil engineering properties and behaviors. Broadcrest provide soil drilling and logging to classify soil properties, including:

  • Particle size, color and description
  • Moisture content
  • Dry density
  • Shear and bearing strength
  • Compaction potential

To learn more about the tests Broadcrest offers click here.

Geology Classification

Geology is classified based on the type (e.g. sandstone) and strength. It is important to investigate and classify rock when large scale excavation and/or structures are planned. The classification of geology involves taking rock core samples to determine the:

  • Rock type
  • Colour and mottles
  • Fractures and bedding
  • Bearing capacity and hardness (through I50 point index strength testing)

Borehole samples are sent to a NATA accredited soils laboratory to be classified and tested in accordance with Australian and international standards. Broadcrest provides detailed reports explaining the soil and rock classification results with comments and recommendations for your project.

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