I think your gut is right.
Mudstone, and most rocks are typically designed as drained materials. Provided the material is jointed, you can use the Hoek Brown criteria to calculate drained parameters. For a mudstone, id guess something like phi of 28 degrees, c' 50-100kPa. Thats a big shot from...
you dont describe SAND as stiff, granular soils are referred to as loose to very dense.
You most likely have a cemented SAND or SANDSTONE, a CLAY would not stand 27m high for 10 years. A cemented SAND would be better called an intermediate geotechnical material as its between a soil and rock...
just assume 17*2.5, dont over complicate it.
Check Das book on Foundation Engineering and Geotech engineering, it has a very good illustrative examples of what to do with water table.
ps- I never use saturated or dry unit weights, I typically just go with above or below the water table. Most...
what type of wall is it? upload pictures and a cross section/sketches
You cant just assume 14 deg, without knowing the actual angle, you will need to do a sensitivity check and pick worst case
In cohesive soils, the near surface soils are in tension so your math is correct. Have you ever walked in an area of CLAY and noticed desiccation and tension cracks. The tension cracks form due to the negative earth pressure. It essentially means that they have some stand up time.
horizontal...
In my world of earthworks, the only thing that permits you to place more fill material (pavement or general fill) is whether you hit your 90-95% density target and either an undrained shear strength or CBR target
The reason we use dry density, it that it is irrespective of moisture content...
sorry will look in more detail when i get a chance. but I do remember and thread where Fatdadd (forum member) as commenting about the need to double the earth pressures estimated similar equations. ill try did it out when i get a chance
The odd rootlet or branch is acceptable, they can be hand picked out. The materal in your pics is not acceptable, even if the came back with an organic test saying less than 3% I would not accept it.
Also it’s normally % weight not volume. You can’t measure organic volume in a lab
Can someone educate me. I presume you are referring to a vibrating wire strain guage? I have never seen these used on a static load test, only a simple dial gauges.
Is there a standard that recommends both or is it just belt and braces approach?
in 55 years the soil should have consolidated, and you will get an increase in undrained shear strength and thus allowable bearing capacity. Difficult to say how much, it can be estimated but does take a bit of work.
How large is this vessel, for most large foundations, bearing capacity is not...
In terms of geotechincal stability, id have to crunch the numbers on it but it looks like it would be fine.
Now there's some structural detailing thats needed, like ensuring the loads from the house are transferred to the new L wall footing.
How is the old wall and new wall attached? they need...
People mainly due CU tests to determine effective stress parameters. This is because a CD takes way too much time and is too expensive. CU with pore pressure measurements should gave the same effective stress parameters as CD tests.
There is no undrained phi angle for cohesive soils. There as...
