How do you calculate vertical stress?
Total stress below a river or lake The total stress is the sum of the weight of the soil up to the surface and the weight of water above this: Vertical total stress at depth z, sv = g . z + gw .
What is boussinesq’s influence factor?
Here, is the Poisson’s ratio of elastic soil medium and Poisson’s ratio range is 0-0.5 for linear elastic materials and. is the Westergaard influence factor. The Boussinesq’s equation gives larger values of vertical stress when , which means that the stress increase is significant.
Which is more accurate method of determining the vertical stress at any point?
Explanation: The Influence chart or the influence diagram is a more accurate method of determining the vertical stress at any point under a uniformly loaded area of any shape than the equivalent point load method.
How is influence factor calculated?
The influence factor is calculated in three points of reference: at the embedment depth of the foundation, at B/2 from the basement level ( I zp, max ) and at 2B from the basement of the foundation.
What is Boussinesq’s theory?
The Boussinesq theory for the distribution of stresses in a half-space resulting from surface loads is largely used in road engineering. It is based on the assumption of linear-elastic homogeneous isotropic half-space for the soil media.
Is not the vertical pressure distribution diagram which can be prepared by Boussinesq’s theory?
1. ____________ is not the vertical pressure distribution diagram, which can be prepared by Boussinesq’s theory. Explanation: By means of Boussinesq’s stress distribution theory, the following vertical pressure distribution diagrams can be prepared, stress isobars.
What is Newmark’s influence chart used for?
Newmark’s Influence Chart is an illustration used to determine the vertical pressure at any point below a uniformly loaded flexible area of soil of any shape.
Is not the vertical pressure distribution diagram which can be prepared by Boussinesq theory?
What is Fadum’s chart?
A concentrated load of 400 kN acts on the surface of a soil. Determine the vertical stress increments at points directly beneath the load to a depth of 10 m. For points below the load r = 0 and at all depths r/z = 0, whilst from Fig.
What is the main difference between the solutions proposed by Boussinesq and Westergaard?
Westergaard’s assumptions mainly reduce the stresses obtained directly below the center of the load as compared to the Boussinesq solution. However, at a certain distance away from the center, stresses obtained from Westergaard begin to exceed those calculated from Boussinesq.
How does Newmark’s influence chart determine vertical stress?
Newmark (1942) developed influence chart to determine the vertical stress due to loaded of area of any shape, irregular geometry at any point below the loaded area. A uniformly loaded circular area of radius r1 is divided into 20 divisions (say the first circle in Figure 8.1).
What do you mean by Newmark’s influence chart?
Newmark’s chart is a graphical representation of Boussinesq’s theory. Newmark developed a graphical procedure for determining the vertical stress below the uniformly loaded area. The chart developed by Newmark’s is also called “Influence Chart”.
When was Boussinesq’s influence chart created by Newmark?
In 1942, Newmark expanded on Boussinesq’s work by constructing what is now very widely known in geotechnical engineering as Newmark’s influence chart. ^ a b c d e f g h Das, Braja M. Principles of Geotechnical Engineering.
When did Nathan Newmark solve the soil stress problem?
In 1883, he solved the problem of stresses produced at any point in a homogeneous, elastic, isotropic soil medium as the result of a point load applied on the surface of an infinitely large half-space. Nathan Mortimore Newmark (1910-1981) attended Rutgers University.