Questions related to the use of soils in engineering, as a material, or as object of research. Some common uses in Civil engineering are as surface for water flow, for foundations, as part of pavement structure, as seepage medium, or as origin of loads over other structures. Other uses in agronomic engineering, or biology, are as medium for storage of water, cultivation, as an erosionable agent, as a souce of receiver of contaminants.
Questions tagged [soil]
34 questions
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How to determine the lateral earth pressure in a double-walled cofferdam?
The design of a retaining wall commonly involves determining the lateral earth pressure using either Rankine theory or Coulomb theory. Both theories involve mobilising the shear resistance of a triangular wedge of soil extending for a considerable…
Question Overflow
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Soil swelling and mass/volume relationships
Given moisture content, Specific gravity of solids, initial volume, and weight. I'm asked to compute the moist unit weight, dry unit weight, and degree of saturation of this compacted soil. This is already done. This compacted soil sample was then…
Gon
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What is the unbraced length of a pile in soil?
When analyzing a pile or drilled shaft as a beam-column, how do you determine the unbraced length of the portion that is in the ground? Typically, the braced points on a beam or column are well defined, e.g. there are connections at discrete…
hazzey
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Why is this construction site pouring gravel over a wire mesh, and then covering it with dirt?
My office is afforded a prime view of a construction project where the workers are currently covering the leveled ground in a wire mesh, raking gravel across the entire mesh, and then covering that gravel layer in another layer of dirt.
What is the…
TylerH
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Settling of unevenly loaded storage tank
Suppose I have a concrete tank, round, vertical, diameter in the range 16m-24m. One half the floor is filled with gravel or concrete to a height of maybe 2 meters. When the tank is empty, that will mean I have about 5 tons per m² more weight on this…
mart
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How are the structural properties of intentionally frozen soil determined?
Soil freezes naturally all of the time. It is at this point that dirt work usually stops.
Occasionally soil is intentionally frozen to improve its structural properties. This process has been used notably in Boston's Big Dig and the Fukushima…
hazzey
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What diameter of particles will result in a blocked borehole?
My mine is looking to install a 600 mm open borehole to drop particles up to 150 mm through. It's a 320m shaft to drop ballast down to save time compared to using the drift.
When it gets blocked they typically take a water truck out and that…
Scott
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How does excess water makes soil compaction more difficult?
I understand how water content helps compaction, by being kind of a lubricant between the soil particles, that helps them slide into position. But I don´t really understand how it starts affecting negatively after surpassing the optimum water…
piguiligui
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What is the effect of ageing on preconsolidation pressure?
Preconsolidation pressure is the maximum effective vertical overburden stress that a particular soil sample has sustained in the past.
How far in the past does the soil remember its loading/the pressure it sustained?
In other words, suppose that…
Bibek Panthi
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Is it possible for a silt soil to be compacted hard as a rock?
I had been told that a silt soil, when professionally compacted (from all the laboratory essays to the compaction with a vibratory roller), ends hard as a rock, and when hit with a metal bar it makes a metallic noise.
I find that hard to believe. Is…
numef
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What is a safe soil load to avoid settlement?
For residential design, looking at IBC 2012 Table 1806.2 it seems a safe soil load to design for is 1500 psf if you want to save time and cost isn't yet an issue. (assuming you're not building on a swamp)
Aside from the problems of swelling and…
thejonster
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Total lateral pressure from clay soil when hydrostatic pressure is also present
I'm stuck with how to work out the total pressure and centre of pressure in this example.
At an outdoor boundary between two properties there is a stepped change in ground level of the clay soil. The ground abruptly changes level by H (roughly 0.9 -…
Stilez
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What paint/spray on material should I use to insulate a metal pole?
I am not entirely sure if this is the correct forum to ask this question so please refer me on if there is a better arena.
I am creating a small weather station and I wish to measure soil temperature. I am aware that digging a hole and then burying…
PaulBarr
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Testing specimens by dropping a ball on them and counting the number of drops required before the collapse. A better way?
A huge number of specimens are built. For each specimen, soil is mixed with cement (and Zeolite) with different percentages. It's intended to test, measure and compare the impact strength of the specimens.
One test option
One test approach is to…
user3405291
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Why is the wet/dry boundary of ground not dangerous for foundations?
A building, such as a house, rests on a foundation. Beneath it is natural earth.
When it rains, the ground around the foundation becomes wet. But the ground underneath the foundation does not. There is a wet/dry boundary somewhere near the edges of…
DrZ214
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