Bearing Capacity

Definition

Bearing capacity is the ability of soil to support the loads applied to it without experiencing failure or excessive settlement. This concept is crucial in determining the suitability of different foundation types, ensuring that structures can be built safely and sustainably, taking into account various factors like soil conditions and load distributions.

5 Must Know Facts For Your Next Test

1. The bearing capacity of soil varies significantly depending on factors like soil type, moisture content, and compaction levels.
2. Compaction methods improve bearing capacity by increasing soil density, reducing void spaces, and enhancing friction between soil particles.
3. Calculating stresses in soils due to external loads is essential for determining how much load a foundation can safely apply without risking failure.
4. Different types of shallow foundations are designed based on the specific bearing capacity of the underlying soil to distribute loads effectively.
5. Deep foundations, such as piles or drilled shafts, are used when surface soils do not have adequate bearing capacity to support structural loads.

Review Questions

• How do compaction methods influence the bearing capacity of soil?
  • Compaction methods increase the density of soil, which in turn enhances its bearing capacity. By reducing void spaces and increasing friction among particles, well-compacted soil can better resist applied loads. Different compaction equipment, like rollers or vibratory plates, may be used depending on the soil type and site conditions to achieve optimal results.
• Discuss how bearing capacity affects the design and selection of shallow foundations.
  • When selecting a shallow foundation type, engineers must consider the bearing capacity of the underlying soil to ensure that it can safely support the anticipated loads. A thorough analysis of soil properties allows for proper sizing and type selection, such as spread footings or mat foundations. If the bearing capacity is insufficient, alternatives like deep foundations may need to be considered to prevent excessive settlement or failure.
• Evaluate the relationship between pile capacity and bearing capacity in deep foundation design.
  • Pile capacity is directly related to the bearing capacity of the surrounding soil. In deep foundation design, understanding both static and dynamic methods for determining pile capacity is crucial. Engineers assess how much load piles can transfer to deeper soils with adequate bearing capacities while also considering lateral resistance and settlement under loads. This evaluation helps ensure that structures remain stable over time and can withstand anticipated forces.

Related terms

Ultimate Bearing Capacity: The maximum load per unit area that the soil can support without failure, often calculated for the worst-case scenario.

Allowable Bearing Capacity: The maximum load per unit area that can be safely applied to the soil, usually set lower than the ultimate bearing capacity to account for safety factors.

Settlement:

The vertical downward movement of the ground due to applied loads, which is a critical consideration when evaluating bearing capacity.