Soil is formed in layers due to the physical, chemical, and biological processes that include transformation of soil materials. Soil mechanics is basically the study of soil and its properties in regard to construction purposes. What is Soil Mechanics? Soil mechanics is a discipline of civil engineering that predicts the soil performance characteristics utilizing the…
Stress Distribution In Soil Displacements in soil occur from stresses applied by loading forces. The distribution of stress in soil should be known for realistic estimates of displacements caused by applied loads on the supporting soil. The following methods may be used to estimate the stress distribution of soil for an applied load Q at the center…
Apart from the difficulty that the state of stress is not completely given in a shear test, the direct shear test suffers from the disadvantage that the deformation is strongly inhomogeneous, because the deformations are concentrated in a zone in the center of the shear box. An improved shear box has been developed by Roscoe…
The notion that failure of a soil occurs by sliding along a plane on which the shear stress reaches a certain maximum value has lead to the development of shear tests. In such tests a sample is loaded such that it is expected that one part of the asmple slides over another part, along a…
A second method to determine the value of the coefficient of consolidation is to use only the results of a consolidation test for small values of time, and to use the fact that in the beginning of the process its progress is proportional to the square root of time. In this method the measurement data…
If the theory of consolidation, presented in the previous chapters, were a perfect description of the physical behaviour of soils, it should be rather simple to determine the value of the coefficient of consolidation cv from the data obtained in a consolidation test. For instance, one could measure the time at which 50 % of…
For the theoretical analysis of groundwater flow several computational methods are available, analytical or numerical. Studying groundwater flow is of great importance for soil mechanics problems, because the influence of the groundwater on the behaviour of a soil structure is very large. Many dramatic accidents have been caused by higher pore water pressures than expected….
As an example the flow under a structure will be considered, see Figure10.2. In this case a sluice has been constructed into the soil. It is assumed that the water level on the left side of the sluice is a distance H higher than the water on the right side. At a certain depth the…
Potential and stream function Two dimensional groundwater flow through a homogeneous soil can often be described approximately in a relatively simple way by a flow net, that is a net of potential lines and stream lines The groundwater potential, or just simply the potential, Φ is defined as where k is the permeability coefficient (or…
The second example is concerned with a pipeline in the bottom of the sea (or a circular tunnel under a river), see Figure 9.3. The pipeline is supposed to consist of steel, with a concrete lining, having a diameter 2R and a total weight (above water) G, in kN/m. This weight consists of the weight…