Page 290 - Masonry and Concrete

Paving

289
PAVING

LUMBER FORMS
STAKE SET
A 3 – 5 FT.
RADIUS
CURVED
PLYWOOD
STRING LINE
FORMS
TO MARK
CURVE
SAW CUT AT ENDS REMOVE EXISTING CURB
FIGURE 8-11
Laying out curve at driveway apron.

used, leave the subgrade undisturbed, smoothing loose surface soil
and filling holes left by stones or roots with sand or gravel. Once the
subgrade is prepared, set string lines to mark the finished concrete
height, drive stakes along the length of the string, and erect the form-
work. If a gravel drainage layer is needed, form boards must be tall
enough to accommodate the depth of the gravel as well as the concrete.
Place about half the gravel inside the forms at one time and compact it
with a vibrating tamper, then place the other half and compact again.
If the driveway is large and will require more than one concrete pour,
erect temporary bulkheads where construction joints will separate
pours. Mark on the tops of the form boards the locations of control
joints that must be tooled or saw cut later.
If there is an existing concrete curb at the street, make a neat cut at
either side using a circular saw with a masonry blade, and remove the
curb manually or with a pneumatic hammer. Install an isolation joint
at the cut line on either side of the driveway to separate the existing
curb from the new concrete. If there is an existing sidewalk that will
cross the driveway, the top of the new concrete should be level with
the finish surface of the sidewalk. At the sides of a driveway with an
existing street curb, build curved plywood formwork tall enough to

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