Questions tagged [soil]
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.
34
questions
0
votes
0
answers
22
views
Volumetric water content and EC measurement by Teros 12 sensors from Meter
We are doing Mid scale experiment in lab with soil. We are using Teros 12 sensors from Meter Group to measure the volumetric water content (VWC) and electrical conductivity (EC) of the soil. I wanted ...
2
votes
1
answer
52
views
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 ...
- 149
0
votes
1
answer
1k
views
Relation of shear strength to bearing strength of soil by formula
From formulas:
Shear Strength: $τ = c+ σ'\cdot sin\phi$
Bearing strength such as: $1.3 cN_c+ qN_q + 0.4B_γN_γ$
Now I know that bearing capacity decreases as the shear strength of soil decreases. ...
- 457
1
vote
0
answers
33
views
Effect of area spring at slab on column
Say that a simple building is supported by 4 columns , the column sitting on base slab. I assigned some sort of area spring to the base slab. When the area spring assigned is higher, this cause the ...
- 61
0
votes
1
answer
179
views
Force required to vertically pull a post out of ground with various soil types
I am trying to determine the force required to vertically lift a typical traffic sign post (round, square and/or channel) out of the ground based on typical soil types at standard installation below ...
1
vote
1
answer
172
views
PE exam: situations in which two question choices are close to my final answer: how to pick one?
Consider this question:
I solve this eventual question and my answer is 7.29667:
Among the question choices are 7 x 7 ft and <...
- 149
1
vote
2
answers
1k
views
Civil Engineering - Detailing of free draining backfill and modelling of hydrostatic pressure in retaining walls
It is considered best practise to specify free draining backfill material (eg gravel) to be placed immediately behind a retaining wall. Supposedly, this alleviates hydrostatic pressure on the wall, ...
-1
votes
1
answer
69
views
Hydrostatic Pressure in Soil
In a saturated soil, why is the pore water pressure equal to hydrostatic pressure?
Terzaghi's principle states that the effective stress between solid particles is equal to the total stress $t$ minus ...
- 1
2
votes
2
answers
775
views
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 ...
- 497
0
votes
1
answer
82
views
Missing items in geotechnical reports [closed]
In your experience, what items that should be in geotechnical reports are sometimes missing, and what do you do in that case, can you provide example? Do we look at codes or make best guess and based ...
- 457
1
vote
2
answers
125
views
Does Eurocode allow use of Robertson chart to determine soil type based on CPT results?
It seems that use of the Robertson charts (Robertson, P.K. [1990] " Soil Classification using the cone penetration test" Canadian Geotechnical Journal 27(1), 141-8) to classify soil type based on CPT ...
- 573
0
votes
1
answer
43
views
How much does the weight of urban structures (buildings) affect the compaction (permeability, porosity, density) of alluvial sediments below a city?
Original Question was here.
I live in Van, Turkey. Van City is situated on an alluvial plain beside Lake Van. General geological structure of the area can be seen on pages 43-44 in this conference ...
- 25
3
votes
0
answers
41
views
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 ...
- 31
0
votes
1
answer
252
views
3 x 1 stone under footing and sump crock
I am having a house built and the builder found organic soils during the excavation. They removed the soils and then filled the cavity with 1x3 stone (see picture). This is the corner where the sump ...
- 103
0
votes
1
answer
81
views
Soil mechanics-Geotechnical engineering [closed]
Which is more economical to improve or change the soil that is used to build a structure?
my answer is that it depends on each case, but I would like to get more information, or where to search about ...
1
vote
2
answers
593
views
Is it possible to calculate Young's Modulus of Clay from load-controlled tests?
I'm trying to get the compressive strength (and Young's modulus) of a clay sample.
The method I found is called 'Unconfined Compressive Strength of Cohesive Soil'. According to ASTM D2166M, I have ...
- 180
5
votes
0
answers
94
views
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 ...
- 51
1
vote
2
answers
141
views
How would you calculate the force needed to rotate along the x axis vertical earth anchor in dirt?
I'm a high school student who hasn't had the pleasure of taking physics yet, so forgive me if the answer is obvious. The problem I have involves an earth anchor drilled vertically into the earth.
I ...
- 11
1
vote
2
answers
431
views
Liquid Limit of Soil through Atterberg Tests
My lab is evaluating the liquid, plastic, and shrinkage limits of some soil samples and we are following this video provided by the Missouri University of Science and Technology. The video indicates ...
1
vote
1
answer
37
views
Is it possible to reuse or the oil recovered from a spill?
I don´t know if this is the rifght place to ask this question, but I would like to know if after the remediation of a soil contaminated with hydrocarbon you can reuse or even sell the oil recovered. ...
- 11
8
votes
1
answer
781
views
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 ...
- 187
3
votes
3
answers
624
views
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 ...
- 33
3
votes
1
answer
489
views
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 ...
- 31
1
vote
2
answers
11k
views
What is the physical meaning of Cumulative Passing% in Grain Size distribution?
When preforming a grain size distribution on a sample of Soil using Mechanical Sieves (e.g. Sieve #4 and sieve #10 and sieve #40) one of the necessary calculation need for drawing the particle size ...
- 11
3
votes
1
answer
2k
views
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 ...
- 571
1
vote
0
answers
254
views
How to derive Darcy's law only in the case of saturated soil without derived all cases?
How to derive Darcy's law only in the case of saturated soil in mathematical/theoretical way without having to derive all the cases?
I can only find the generalized theoretical proof for all cased ...
- 203
2
votes
1
answer
78
views
Penetration rate for miniature cone
Is there any recommended/suggested/required penetration rate for a miniature cone penetrometer? A 20mm/s is for a standard size of cone penetrometer, what about for miniature one?
- 21
4
votes
3
answers
7k
views
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 ...
- 41
2
votes
1
answer
72
views
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 ...
- 121
11
votes
1
answer
1k
views
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 ...
6
votes
2
answers
175
views
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 ...
- 10.7k
7
votes
1
answer
3k
views
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 ...
- 10.7k
10
votes
2
answers
2k
views
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 ...
- 101
7
votes
1
answer
205
views
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 ...
- 4,772