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

3. A V-groove finish will not only provide good traction, but will also assist
in "cleaning" the launching ramp surface in response to boat wakes, wind
and storm waves, and rainwater running down the ramp. Sand, soil and
other debris will tend to be carried down and off the sides of the
launching lanes and launching ramp. Therefore, the direction of the
V-grooves should be determined in consideration of the following:
a. direction of prevailing wind, waves and
currents;
b. source of sand, silt and other debris on
the launching ramp;
c. number of launching lanes;
d. topography of the site; and/or
e. presence of abutments and boarding
floats on the launching ramp.
4. On wide, multiple lane launching ramps, it
is advantageous to alternate the direction of
the V-grooves from lane to lane, thus
forming a "herringbone" pattern. This
provides a distinct permanent delineation of
the launching lanes. Changes in the
direction of the V-grooves should never be
made except at launching lane lines.
E. V-groove tool design varies in size, shape,
weight, and material used for fabrication. Steel,
aluminum and wood tools have been used
successfully. However, it appears that aluminum Figure 16. "Herringbone" V-Grooves
is perhaps the best choice in consideration of the
tool's size, weight, and the ease and speed with which a finisher can produce
crisp, straight V-grooves in wet concrete.
1. V-Groove Tool Design (for a tool to be used to finish large areas of castin-place
concrete; smaller modified tools should be used for precast
panels)
a. Weight: 22# to 25#
b. Length: 24” to 30”
10
Figure 15. V-Groove Detail