layout, design and construction handbook - California Department of ...

202. Construction Details and Materials
A. Launching ramps are to be constructed of reinforced concrete, using one or a
combination of the following:
1. Cast-in-Place Concrete
a. Fresh Water Installations
6” thick over aggregate base
3” rebar cover at bottom
b. Salt Water Installations
8” thick over aggregate base
3” rebar cover, top & bottom
c. Full ramp slab thicknesses of 6” and 8”
are to be constructed. Reduced slab
thicknesses based on the nominal width
of conventional form lumber should not
be accepted.
d. Minimum steel reinforcement should
be #4 rebars (1/2” diameter) at 12”,
both ways, or as required by the design
engineer.
2. Precast Concrete Panels and Planks
a. Precast concrete panels are typically 3’
to 5’ in width, up to 50’ long, and are
placed over aggregate base. Panels of
this size are typically 8” thick, weigh
up to 12 tons each, and must be
specifically designed to withstand
lifting stresses during manufacture,
shipping and placement.
b. Precast concrete planks are
considerably smaller than precast
concrete panels, typically being 12” to
24” wide, and up to 15’ long. They
should be not less than 6” thick, and be
designed to bolt, cable, clip, key, or
otherwise fasten together during
installation. In quiet
7
Figure 7. Fresh Water Launching Ramp Slabs
Figure 8. Salt Water Launching Ramp Slabs
Figure 9. Typical Concrete Precast Panels
Figure 10. Typical Precast Concrete Planks