Hello colleagues,
We are currently working on a project that involves determining the gradation of 24"-minus rockfill. We've been searching for standard procedures, such as those provided by ASTM, but unfortunately, we haven't found any suitable ones yet. If any of you are aware of any...
If you would have to review a report where for the situation described above the clay layer was divided (vertically) into two layers: one below the embankment (representing NC clay) with undrained shear parameters and one at the toe and away (representing OC clay) with drained shear parameters...
Thanks Dave,
The only problem with what you suggested is that this would be correct for the (infinite) line load along the wall. In my case, I have a finite loaded area.
Good morning
We have a 20 m high retaining wall with a 4x4 m footing seating right beside the edge of the retaining wall. How can I estimate an equivalent lateral force (and its location) on the wall caused by the footing? I've been thinking of two approaches so far but I am not sure if are...
ntschwanz, thank you once again for your input. So basically it all boils down to Pore Water Pressure (PWP), PWP dissipation (whether water makes its way in or out of soil) and dissipation rate. If we could calculate the exact PWP at any location at any point of time, there wouldn't be a need...
Thank you once again.
I would also appreciate if you could address my question on overconsolidated clay.
How different the situation could be if we had overconsolidated clay instead of normally consolidated?
If I remember correctly, overconsolidated clays tend to lose their strength over...
Thanks a lot ntschwanz.
How different the situation could be if we had overconsolidated clay instead of normally consolidated?
If I remember correctly, overconsolidated clays tend to lose their strength over time and usually drained conditions are more critical to analyze. What if the clay...
Hello all,
I have a question (and maybe not the smartest one in the world) that got me confused.
Let’s say there is a normally consolidated clay layer overlain by sand and gravel deposit. There is a dam constructed on top of the sand and gravel deposit. Dam weight introduces excessive pore...
I am looking for information on earth dams/cofferdams built by dumping in the water. The question of interest is what slope would the material under water be if dumped from a barge or by end-dumping from trucks. The material could be rock fill, low plasticity clayey silt (50-60% fines) and sand...
Thanks BigH. The thing that is still confusing me is that none of the sources I’ve read including Duncan and Wright attempts to differentiate between OC, NC or Slightly OC materials for long term stability purposes. The guidelines are clear to use drained strength for all materials. In any...
To: BigH
I appreciate your answer and thanks for the reference. Just clarify a few points. Here is the definition given by Duncan and Wright “Soil Strength and Slope Stability” (2005) on short term conditions: “Short term refers to conditions during or following construction—the time...
To: GeoPaveTraffic
I assume you base your statement "CPTs have little use for slope stability" on some sources, textbooks etc. Could you please refer me to a few of them. I am just curious to see what they are based on.
BTW, my original question was on how to process CPT data for the slope...
To: GeoPaveTraffic
Can you please elaborate a bit more on variability of material properties between short term and long term conditions?
Regarding the consequences of failure, you say that there is no difference between consequences of dam failing right after construction (before it fills...
To: GeoPaveTraffic
Thanks for the professional ethic lesson, but I’ve been through it and have a really good idea of what the responsibility means. If I feel that I need more data I’ll get it, but that’s not the case. CPT is widely recognized as a standard field test to collect data on...
To: BigH
Thanks for your response. I still don’t get it both formally and mentally [dazed]. The US Society on Dams “Strength of Materials for Embankment Dams” (http://www.ussdams.org/07materials.PDF), USACE Publications such as “Stability of Earth and Rock-Fill Dams”, Duncan, J., & Wright, S...
To: GeoPaveTraffic
Something tells me that variability in material properties, groundwater conditions, loads etc. can be applied more or less equally to both short-term and long-term conditions. May it be related to the probability of loading conditions and consequences of failure instead?
To: GeoPaveTraffic
Thanks. Your questions relate to short term (changes) conditions, but I specifically asked about the long term stability assessment where pore water pressure corresponds to steady seepage conditions or in your words “there has been no change in stress for a long time”.
Hello again,
I am looking for a good summary on origins of FOS for short and long term slope stability. What is the main reason for the "short-term" FOS to be lower than the "long-term" one?
Thank you in advance,
CEMAB
Hello,
I would appreciate if you could share your experience on processing CPT data for the slope stability purposes. To be more specific, I have a record of interpreted undrained shear strength obtained from CPT. The Su values fluctuate substantially with the depth (see the attached file). I...