Being based in the UK, I have to admit that the level of reliance on plate load testing is not always matched by an understanding on what the plate load test is actually measuring, let alone test laboratories not following the instructed procedure. However, if undertaken to an appropriate...
There are a couple of options which you can consider, dependent upon what is trying to be achieved and what is being supported.
Option 1: The piles are there to support the element above, and any settlement is limited to the contribution from piles, not the surrounding ground. For the load...
Hello everyone
I know that there are many posts relating to the use of the CBR as well as the subgrade stiffness. I have a background in construction materials testing (20 years) and have spent the last 20 years as a Geotechnical Designer/Civil Engineer specializing in earthworks and...
The use of air void contents is a guide to an end product assessment of fill, best suited for cohesive fill material. In the UK, the code of practice for earthworks would be a good starting point, BS 6031:2009, and across Europe including the UK, you also have BS EN 16907-1 TO 6: 2018, which...
If you are using the gauge to calculate the air void content direct, please be aware that the readings are not corrected to the soil under teat and that you will have to ensure you have entered the correct particle density for the soil under analysis.
The gauge will give a reading on the bulk density, moisture content (and dry density). The gauge should be calibrated against the soil, so the readings can be corrected.
The results will give you the dry density and moisture content can then be used to calculate air void content, for which you...
Whilst you may be outside of the UK, the UK does have very clear guidance on this published by the NHBC (National House Building Council) which includes the depth of foundations, AND not limited to just considering the stiffness and bearing capacity of the soil.
There is an update to the NHBC...
If you change the stiffness of the plate, the stress distribution in the ground will change. See rigid, semi-rigid and flexible stress distribution figures, in all geo text books.
I know there is great reliance on degree of compaction and air voids as a means of end product testing of fill, but ultimately the critical attributes for the fill would be by their end performance.
I have used both rolling dynamic compaction and high energy impact compaction (e.g. Bomag BW...
I think that there is either a fundamental error in the testing or the reporting. The plastic limit is the moisture at which the soil begins to behave in a plastic manner, below this moisture the soil is dry and friable. The liquid limit is the point where the soil begins to behave in a...
This sounds very similar to a project I am aware of. Just a note of waring, check the underlying soils below the Made Ground and make sure of their engineering performance before embarking on widespread excavation and re-engineering.
If they are competant, should be OK but you should always...
Make sure when you do the testing you include the following:
Water soluble sulfate;
Acid (Total) sulfate;
Total sulfur;
organic content;
Initial consumption of lime (add lime in 0.5% increments and measure the resultant pH, where the pH stops increasing this is the ICL, add 0.5% to this and use...
Sulfates, sulfates and sulfates!!!
Lime treatemnt to modify soils is equivalent to drying a wet soil to an acceptable range and the long-term performance will be consistent with this. With the addition of quick lime, this will hydrate (the lime uses some of the water in the soil) and with the...
BS EN 1997-2 (Eurocode 7) Annex K discusses a range of methods for assessing plate load test results, which in turn can be used to assess the undrained shear strength, or plate settlement modulus. The equations are no different to many soil mechanics textbooks, but they are encapsulated in a...
You should also look at the overall gradings of the two materials. If you remove coarser material you will change the grading. The moisture in the compacted material acts as a lubricant to aid the packing of the material and also fills some of the voids. If the grading is different, so will the...
The technical paper was 'purely' for working platform desin, no more than 2m required in accordacne with BRE BR470 if theunderlying soils are consitent.
There was a very good Technical Paper in the Ground Engineering magazne in Fenruary of this year which looked at the use of the Plate Load Test to back calculate the angle of shearing resistance using a notional failure settlement of the plate to determine the ultimate bearing capacity. Then...
Ah well, I guess I probably made it sound like it was all clearly defined and there was no scope for good engineering.
It does depend on the structure to be built but also when you go through the appendicies they are direct copies out of the text books 'we' have always used, presented as...
