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  1. figurnitout

    LRFD Pile Cap Design

    Hello, I was hoping that someone could point me in the right direction. I am a one man show engineering firm and my main focus is temporary works for bridge construction. Because AASHTO Temporary Works rarely (if at all) requires LRFD, I have never learned how to do LRFD. This hasn't been a...
  2. figurnitout

    Help Converting Static Bending Properties to Fb ?

    More great questions. The bridge was originally designed to handle a Link-Belt 218 crawler crane (see attached drawings). The contractor now wants to deliver concrete via the bridge. The beam spacing was originally designed to accommodate the crane, therefore the beam spacing needs to remain...
  3. figurnitout

    Help Converting Static Bending Properties to Fb ?

    Great questions. Attached is sketch. Concrete trucks will drive across this temporary bridge. The liability is mine. I am aware that I could easily double the mats, or place timbers (or even steel plates) longitudinally under the wheel paths. The cost of the materials gets very high very...
  4. figurnitout

    cart on plywood

    Spanning 4' and using ¾" Class 1 Plyform, Fb=1500± psi, the maximum load you'd want to place on the plyform would be around 20 psf which isn't much if you are moving equipment over it. You would most likely need joists or some other support under the plywood and space it at whatever your load...
  5. figurnitout

    Help Converting Static Bending Properties to Fb ?

    Hello, I am performing a design check on timber crane mats that will be used in a bending application. In the literature provided by the material supplier (attached), Fb is not given. The properties given are Static Bending Properties, ie, Modulus of Rupture, Modulus of Elasticity, Work to...
  6. figurnitout

    Need help applying tire load to timber deck

    The timbers are made primarily from oak. I am familiar with NDS, but didn't trust it for this application because the numbers differ greatly between NDS and what the supplier says the mats are made of (attached). For instance, the values in NDS for shear parallel to the grain for oak is...
  7. figurnitout

    Need help applying tire load to timber deck

    Here's the other attachmenthttp://files.engineering.com/getfile.aspx?folder=2708504a-2ba3-436d-bf6d-a54972cb000a&file=Chap_4_-_Strength_Properties__-_partial.pdf
  8. figurnitout

    Need help applying tire load to timber deck

    The paper was outstanding. Thank You! I have another question if you can help me... For checking bending stresses, I would typically compare the actual bending stress, fb=M/S to the allowable, Fb. However, in the literature that I was given from the material supplier (attached), Fb is not...
  9. figurnitout

    Need help applying tire load to timber deck

    That's a great point. If the timbers are bolted together, the mat would act as a unit distributing the half axle (tire) load over two 12" timbers. Thanks for the help!
  10. figurnitout

    Need help applying tire load to timber deck

    Thanks a lot! That's a huge help. Actually, I designed the bridge to handle a Link-Belt 218 crawler crane. The sideframes are centered over each girder pair (so there is(was) only compression on the timbers). I wasn't worried about the timbers until the contractor mentioned to me that he...
  11. figurnitout

    Need help applying tire load to timber deck

    I am checking the adequacy of 12" x 12" timber crane mats being used as the deck for a temporary construction work bridge. I am not sure how to apply the tire loads to the deck. This is my first post, so I will attempt to attach a sketch. The tire load is 12,000 lbs (concrete truck). The tire...

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