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  1. molerat2210

    Shear Strength Testing for Gravel Materials

    A large scale direct shear test of a cobble fill would be reasonable if it can demonstrate a higher friction angle for design. Hopefully, any test cost would be offset by savings for embankment borrow. Good luck finding a lab that can do it. It would probably need to be custom built.
  2. molerat2210

    Soil Friction

    Brad, Pipe thrust results at pipe bends, valves, reducers and line stops for pressure pipes. These forces need to be calculated and restrained by the appropriate method. This is why pipeline designer ask questions like: "what is coffecient of friction for the soil/pipe interface". In the...
  3. molerat2210

    Need a book for soil corrosion

    OK. Thanks Ron. That is a good overview. I am looking for a bulky tome on the subject (something like 500 pages).
  4. molerat2210

    how do you calculate the design cbr value from a range of on site cbr values

    Personally, I do not like to fill potholes so I design towards to worst case. If the worst case areas can be isolated and improved/stabilized then that will save someone money vs a thicker section. If the owner wants to accept the maintenance issues related to a lower CBR then that is thier...
  5. molerat2210

    Need a book for soil corrosion

    Does anyone know of a good book for soil corrosion test methods, evaluation of soil corrosion for various material types, and design principals for passive and active protection systems? Thanks in advance.
  6. molerat2210

    Odometer on a soil sample (clay)

    The UU vs CU question gets asked frequently. Please search the previous threads.
  7. molerat2210

    Driled Pier Horizontal Deflection Limit

    IBC limits the service lateral load to 1/2 the load that produces 1 inch of deflection. I presume the seismic lateral earth pressure is a service load.
  8. molerat2210

    Testing Existing Caissons

    This program is about $150K. That's a fraction compared to costs of new foundations. I feel this is somewhat innovative. I usually see the old foundations abandoned. There is an alternate plan to test only 5 (like Ron suggests). It will be for the strutural engineer to decide.
  9. molerat2210

    Testing Existing Caissons

    Thanks for the more good advice. I think I have settled on the plan. The specs will require the contractor to test all 63 using ASTM D 4945 and core 5. I like the idea of getting intergrity test data above the bell. I do have the as built drawings, which are the original drawings stamped "as...
  10. molerat2210

    Soil Friction

    There is a lot that goes into design of thrust restraint for buried piping. Are we talking about thrust restaint? The question is not clear at all? Are we talking about soil-pipe interface angle for design of restrained joint pipeline? Pipe material and pipe envelope backfill material would...
  11. molerat2210

    Testing Existing Caissons

    Thanks massagung, I did change the testing plan to HSDT ASTM D4945. HSDT tests appeared to be limited to test loads of 2500 tons. That per test cost of statnamic test is very high and not well suited to this job since we want to test every caisson.
  12. molerat2210

    Certification Versus the "real" world

    Mike, Come to think of it there are more than a few lines in the standards that I am pretty sure most labs ignore. There are minimum sample size requirements. We can't meet that requirement all the time for spoon samples. We can only get much material into a split spoon.
  13. molerat2210

    Testing Existing Caissons

    Aeoloantexan, I had the wrong diameter in my first post. The largest shafts are 5.5 feet diameter and 8.0 foot diameter bell with allowable bearing pressure of 50 tsf. From that, the working stress in the shaft was 1470 psf. As built drawing says 3000# concrete for caissons. The buiding was...
  14. molerat2210

    Certification Versus the "real" world

    I have also managed an AASHTO lab in years past. In the beginning there were 2 schools of thought: 1) do it the right way (i.e., following every letter of the standard), 2) do it the old way and put on a show for AASHTO. In the end, you will find it is easier and more cost-effective to do...
  15. molerat2210

    SPT vs RQD data slope analysis

    If it is a rock slope then you need to classify the rock mass using RMR or Q-system. This is engineering geology stuff (I defer to the geology people on this). There are some free software (rocscience.com) to compute the c and phi from RMR. From that you can do your stability analysis...
  16. molerat2210

    Uplift pressures on dams

    There is an army corp of engineers manual for gravity dam design. All the formulas, etc. are in there to calculate uplift. Finite element software not needed.
  17. molerat2210

    Testing Existing Caissons

    Aeoliantexan, It is a heavy concrete building. Your idea is a good one. We probably will not need 2,500 ton column loads in the future but we don't know what we want to build yet since this is the demo phase. The thinking right now is to get some feasibility information for concept...
  18. molerat2210

    Pile Integrity Test

    Pile intregrity test and pile load test are two separate categories. You have listed various types of static and dynamic load tests.
  19. molerat2210

    Testing Existing Caissons

    I am interested to re-use 63 existing caissons (i.e., drilled shafts)that supported a previoius building. The shaft diamters range from 3.0 to 4.5 feet and the bell diameter ranage from 5.5 to 8.0 feet. As built drawings indicate caissons constructed on sound bedrock for an allowable bearing...
  20. molerat2210

    Russell Silt Loam

    Where do I begin with the stupidity of this exercise? How about it's prepared by the USDA for agricultural use. How about it only considers the top 48 inches. How about following IBC and conducting a geotechnical evaluation as the code prescribes? I am sorry for being mean. But, seriously...

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