Page 292 - Masonry and Concrete

Paving

291
PAVING

1 /2" ISOLATION JOINT AT
EXISTING SIDEWALK

CENTER SECTION
EDGES
FINISHED LEVEL
TAPERED
UP TO
CURB

1 /2" ISOLATION JOINT
AT STREET
FIGURE 8-13

Forming driveway apron edges.

8.2.2 Sidewalks
The site preparation, formwork, pouring, and finishing operations for
sidewalks are essentially the same as for driveways. Because they do not
carry the weight of automobiles, gravel beds are not typically used
under sidewalks unless drainage is very poor, but a layer of coarse sand
is used as a cushion, leveling bed, and capillary break to keep soil mois-
ture from continuously saturating the concrete and accelerating corro-

MAKING A SLOPED STRIKE OFF BOARD

If you want the driveway to be higher in the middle than the edges so
that water will drain to both sides, or if you want it lower in the middle
to channel water away, you will need to make a sloped strike off board.
For a crowned driveway, lay a 2 ✕ 4 and a 2 ✕ 6 edge to edge and nail
them together in the middle by overlaying a piece of scrap wood. Insert
small wooden blocks or wedges at the ends to hold the boards apart the
required distance (Figure 8-14). Nail a piece of scrap wood near each
end to hold the shape. For a driveway that drains toward the middle,
nail scraps of wood at the ends first, and then drive a wedge or block in
the middle before nailing.

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