Return to index: [Subject] [Thread] [Date] [Author]


[Subject Prev][Subject Next][Thread Prev][Thread Next]
 	I have been following this thread and agree with the previous comments.
However, I think you may want to consider concrete pipe or a cast in place
circular section constructed vertically.  This has some obvious advantages
for engineering and construction. Not knowing your mechanical layout I am at
a disadvantage.  I have used concrete pipe in this app. many times. If you
are worried about joint leakage you could utilize concrete pressure pipe for
info. check out the American Concrete Pressure Pipe Assoc.

I am seeking some comments with regard to the design of a
          deep wet well which will contain a submersible pump to
          discharge storm water.  The structure will be a square box
          (4' x 4' interior dimensions) that extends from the ground
          surface to a depth of 32 ft. below grade.  The structure
          will be reinforced concrete and is subject to an equivalent
          lateral pressure of 100 lbs/ft^3 (i.e. lateral pressure =
          100 * depth).  Utilizing PCA's "Rectangular Concrete Tanks
          Book", and with ACI 350 in mind, I'm getting a wall
          thickness at the bottom of the structure in the neighborhood
          of 22" thick (shear design controlling).  The client thinks
          this is ridiculous and we're over-designing.  They also say
          they have never seen anything over 18" thick and usually
          it's 12" thick.

          What typical wall thickness have others arrived at for these
          types of buried structures ?

          We are not utilizing shear reinforcing in the corner of the
          tank to handle shear (only the concrete's ability to take
          the shear).  We are thinking it will be easier to construct
          with minimal rebar and more concrete.  Any different
          philosophies out there ?

          Thanks in advance for any help.