Theoretical Foundation Engineering
Featuring an easy-to-understand format where detailed mathematical treatment is kept to a minimum, this in-depth book provides numerous charts, drawings, and illustrations to illuminate the problems and theory.
TABLE OF CONTENTS Theoretical Foundation Engineering
4.10: ULTIMATE BEARING CAPACITY DUE TO VERTICAL ECCENTRIC LOAD
4.10 ULTIMATE BEARING CAPACITY DUE TO VERTICAL ECCENTRIC LOAD
Based on several laboratory model tests, Meyerhof (1953) has suggested a semiempirical procedure to determine the ultimate bearing capacity of shallow foundations due to eccentric loading condition. Eccentric loading of shallow foundations occurs when a vertical load Q is applied at a location other than the centroid of the foundation (Fig. 4.36a), or when a foundation is subjected to a centric vertical load of magnitude Q and a momentum M (Fig. 4.36b). In such a case, the load eccentricities may be given as
Figure 4.36: Eccentric load on shallow foundations.
and
where
| e L, e B | = | load eccentricities, respectively, in the direction of long and short axes of the foundation |
| M B, M L | = | moment about the short and long axes of the founda-tion, respectively |
According to Meyerhof (1953), the ultimate bearing capacity q u and ultimate load Q u of an eccentrically load foundation (vertical load) can be given as
and
where
| A ? | = | effective area = B " L" |
| B ? | = | effective width |
| L ? | = | effective length |
The effective area A ? is a minimum contact area of the foundation such that its centroid coincides with that of the load. For one-way eccentricity, that is, if e L=0 (Fig. 4.37a), then
Figure 4.37: Case of one-way eccentricity of the load on the foundation.
However, if e B=0 (Fig. 4.37b),...
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