Search results
Results from the WOW.Com Content Network
Cohesion is the component of shear strength of a rock or soil that is independent of interparticle friction. In soils, true cohesion is caused by following: Electrostatic forces in stiff overconsolidated clays (which may be lost through weathering) Cementing by Fe 2 O 3, Ca CO 3, Na Cl, etc. There can also be apparent cohesion. This is caused by:
The cone penetration or cone penetrometer test (CPT) is a method used to determine the geotechnical engineering properties of soils and delineating soil stratigraphy. It was initially developed in the 1950s at the Dutch Laboratory for Soil Mechanics in Delft to investigate soft soils.
The adhesion of the soil textural components by organic substances, iron oxides, carbonates, clays, and silica, the breakage of those aggregates from expansion-contraction caused by freezing-thawing and wetting-drying cycles, [21] and the build-up of aggregates by soil animals, microbial colonies and root tips [22] shape soil into distinct ...
A USBR soil scientist advances a Giddings Probe direct push soil sampler.. Geotechnical investigations are performed by geotechnical engineers or engineering geologists to obtain information on the physical properties of soil earthworks and foundations for proposed structures and for repair of distress to earthworks and structures caused by subsurface conditions; this type of investigation is ...
The soil is free to dilate or contract during shear if the soil is drained. In reality, soil is partially drained, somewhere between the perfectly undrained and drained idealized conditions. The shear strength of soil depends on the effective stress, the drainage conditions, the density of the particles, the rate of strain, and the direction of ...
During the test the pore pressures of fluids (e.g., water, oil) or gasses in the sample may be measured using Bishop's pore pressure apparatus. From the triaxial test data, it is possible to extract fundamental material parameters about the sample, including its angle of shearing resistance, apparent cohesion, and dilatancy angle.
In geotechnical engineering, a tieback is a structural element installed in soil or rock to transfer applied tensile load into the ground. Typically in the form of a horizontal wire or rod, or a helical anchor, a tieback is commonly used along with other retaining systems (e.g. soldier piles , sheet piles, secant and tangent walls) to provide ...
If the soil particles in a sample are predominantly in a relatively narrow range of sizes, the sample is uniformly graded. If a soil sample has distinct gaps in the gradation curve, e.g., a mixture of gravel and fine sand, with no coarse sand, the sample may be gap graded. Uniformly graded and gap graded soils are both considered to be poorly ...