Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations MintJulep on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. Boonie

    MSE Bridge Abutment Footing Depth

    Use free draining stone for the fill. There are also methods to transfer the tensile force from the reinforcements behind the footings and allow your shallow foundation to be buried deeper.
  2. Boonie

    Software for internal MSEW design

    There are others (keywall, Srwall...) but you won't find a more versatile or user friendly software than MSEW.
  3. Boonie

    Stone Retaining Wall Reinforcement

    Who designs stone "rubble" walls with geogrid anyways? The walls are inherently suited for gravity walls. A wet stacked, rigid retaining wall facing is not suited to the flexible characteristics of a reinforced retaining wall system. As Oldest said, do the gravity calcs and see if it works.
  4. Boonie

    MSE Wall hand calculation example

    The NCMA guidelines have sample calcs as well.
  5. Boonie

    Sheet Pile Wall - Aesthetic Facing Options

    MSE blocks can be easily attached to the sheet pile. We have used modular blocks to veneer sheet piles as well as H piles in detention ponds.
  6. Boonie

    Is it wise to use Geogrid and Soil-Cement?

    Long term design strength of the geogrid is based on test data provided by the manufacturer for different types of soils. If you feel confident you are utilizing the correct reduction factors, etc. for the backfill you are using, then ok. If you don't have test data to determine the LTDS of the...
  7. Boonie

    Is it wise to use Geogrid and Soil-Cement?

    The overall strength of the geogrid is based on the mobilization of the tension throughout the full length of the grid. Garrettk has a good point. If you reduce the ability of the grid to "deflect" slighlty within the soil, you will concentrate the resultant forces at the only place that will...
  8. Boonie

    Is it wise to use Geogrid and Soil-Cement?

    HDPE geogrids can be used with soils that have a ph range of 2-12 whereas PET is only good from 5-9. As for using soil cemented fill, you may want to investigate the interaction parameters between the reinforcement type you choose and the cemented soil. Check with the manufacturor for the...
  9. Boonie

    foundation behind MSE wall

    If you are experiencing a geogrid overstress failure mode and not a connection failure, I agree with MSEMan. You can decrease the grid spacings to as little as 6" without causing a constructability problem. This is normal in geogrid structures over 50' tall. The additional grid will be far...
  10. Boonie

    foundation behind MSE wall

    MSE walls are not typically designed for lateral loads other than earth pressures. As long as the vertical loads generated by the sign are transferred to a point below the bottom elevation of the reinforced soil zone, it should not impact the design of the wall. For instance,with a pressure...
  11. Boonie

    Geogrid installation questions

    The FHWA design manual deals with the design and construction of tiered walls. Tiered wall designs will more likely than not, result in the upper wall bearing directly on the reinforced zone of the lower wall. Something to keep in mind, internal and external stability calculations for the lower...
  12. Boonie

    MSE/soil nail hybrid walls

    Thanks for the info. I am designing a small wall that will utilize a soil nail wall with a modular block facing at the bottom and will transition to a standard modular block wall reinforced with geogrid at the top to reduce the required excavation. The internal design is easily performed for...
  13. Boonie

    MSE/soil nail hybrid walls

    Texas Tech has a research project called "Design procedures for MSE/Soil Nail Hybrid wall design". Can anyone help me locate this document or a similar one concerning the global stability analysis of this type of wall system. Design software is readily available to model the walls seperately but...
  14. Boonie

    Placing posts behind geogrid wall

    Drive guard rail posts, don't auger. Insert sleeves for fence posts during the wall construction. This makes things easy for the fence contractor. 4" pvc is adequate.
  15. Boonie

    Segmental Retaining Wall at a Pond, Design Method?

    The critical factor in designing a segmental retaining wall that impounds water is rapid drawdown. Due to the fact you are designing a wall made from dry stacked concrete blocks, the water will obviously saturate the reinforced backfill during high water events. The FHWA design manual for MSE...
  16. Boonie

    Backfill slope

    Point taken. But what happens when the site contractor decides he has too much dirt on site and "cheats" the slope out to about 5 or 6 feet from the wall. Rarely have I seen a slope constructed exactly as drawn on the plans. There are plenty of contractors willing to "field fit" to meet their...
  17. Boonie

    Backfill slope

    Alternatively, you can find the middle ground by using the Coulomb's with the "broken back" angle of slope. It will provide active pressure coefficients somewhere in the middle. A 10' flat area with a 10' 2:1 will generate an 18.4 degree beta angle for the Coulomb's equation. You will also need...
  18. Boonie

    Traffic (live load) surcharges on retaining walls

    I agree, better safe than sorry, use the 250 psf. Have you considered an MSE structure? It may be more cost effective considering the small size of the wall.
  19. Boonie

    Retaining Wall - Driving Moments Greater Than Resisting Moments

    I would suggest using a helical pile to "tie down" the footing. This type system will provide anchorage and give you the ability to resist the moments and driving forces needed to keep your footing within the limits of the right-of-way. Helicals can be placed wherever you require a resisting...
  20. Boonie

    MSE Retaining Wall system design (redi-rock)

    What failure mode is driving your design?(sliding, pullout, global stability). Are you having problems with internal sliding or external? Due to the flexible nature of the segmental systems, rigid foundations are not normally suitable. Modifications to your foundation and retained soil...

Part and Inventory Search

Back
Top