Effect of Embedment on Soil Subgrade Reaction

Foundation Design / Construction

Contents [hide show]

Introduction
Calculation Example
References
Selected Topics
Web Class Assignments

Introduction

The static stiffness of a soil-foundation system tends to increase with the depth and the embedment of a foundation. Subsequently, the settlement of the ground is decreased. The equations that take into consideration the depth and embedment effect for a square shaped foundation (Figure 1) are tabulated in Table 1.

The static stiffness is derived using the stiffness of a surface foundation multiplied by two scaling factors, a & b, incorporated to take into account the depth and the embedment effect, respectively.

**Figure 1**: Effect of embedment depth of a square foundation on the static stiffness of the system

Table 1: Static stiffness of the soil-foundation system for a square shaped foundation on a homogeneous, isotropic elastic half-space considering the effect of depth and embedment.

Calculation Example

A rigid square shaft is founded at a depth equal to its width (D=2B). Using the equations presented in Table 1 (D/B= 2), the static stiffness of the embedded foundation, K, with respect to that of a surface foundation, K_sup, is obtained as:

The results indicate that the depth and embedment can have a significant effect on the static stiffness of a soil-foundation system.

References

Gazetas G. (1983). Analysis of machine foundation vibrations: State of the art. International Journal of Soil Dynamics and Earthquake Engineering, Volume 2, Issue 1, https://doi.org/10.1016/0261-7277(83)90025-6.

Selected Topics

Soil Reinforcement for the Foundation of the Rion-Antirion Bridge Piers Hollow large Diameter Steel Piles Steel Rods manufacturing for the construction of Rion-Antirion Bridge Rion-Antirion Bridge: Views of the Piers, in the dry dock, floating, in place and of their interior Foundation Design / Construction Shaft Foundations Eurocode 7: Past, Present, and Future - ISSMGE Lecture What is Geotechnical Engineering?Soil Subgrade Reaction Soil Subgrade Reaction in Rigid Foundations Soil Subgrade Reaction in Flexible Foundations Soil Subgrade Reaction in Pile Foundations Horizontal Soil Subgrade Reaction in Pile Foundations Buchanan Lecture 2021: video available

Deep Foundations

1 pages

Geotechnical Engineering Photo Album: A collection of photographs for educational instruction by Ross W. Boulanger and J. Michael Duncan

Pile Foundations

1 pages

Pile boring Machines of the 18th Century

Geotechnical Engineering Photo Album: A collection of photographs for educational instruction by Ross W. Boulanger and J. Michael Duncan Reliability of Shallow Foundation Design Using the Standard Penetration Test

Web Class Assignments

Liquefaction During the Loma Prieta Earthquake

CE 179-Geosystems Engineering Design

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The tilt of the Leaning Tower of Pisa: Why and How?

CE 179-Geosystems Engineering Design

The Leaning Tower of Pisa is one of the most famous constructions in the world. Its fame not only comes from the original trigger for its construction – to show the importance of this city after...

An introduction of Micropiles on expansive and karst ground conditions through the design lens of bearing capacity

CE 179-Geosystems Engineering Design

The history of micropiles stems over seven decades ago from Europe though widespread acceptance and standardization of the technology is more recent and has not matured for as long as its first docu...

Helical Piles

CE 179-Geosystems Engineering Design

Helical piles are a form of prefabricated deep foundation. As hinted in its name, helical piles differ from other deep foundations and are most notable for having spiraling blades along their shafts...