DRIVEWAY CONSTRUCTION 2DRIVEWAY CONSTRUCTION 2 Concrete roads, though durable, are ugly unless they have incorporated into their surface stone chips which give an interesting texture and color. There is a recently devised process for doing this which is highly recommended by the originators. For certain situations, even on the private place, however, the regular concrete road such as is used for state highways may be the best type to use. Therefore a brief summary of the specifications for such a road are given, as follows: The subgrade is formed at a depth of 8 inches from the finished grade. Forms are then placed at the edges and firmly pegged in place. These may be either 2 by 8 inch planks or the special lock- joint steel forms now almost universally used. Into these forms the concrete should be poured, first to a depth of 3 inches, whereupon the wire or steel rod mesh reinforcement is placed, and then, immediately, the remainder. At intervals of from 40 to too feet transverse joints made of 7/2-inch asphaltic matrix should be placed. The length of sections varies with the severity of the climate. These allow for the necessary expansion of the pavement caused by the variations in temperature. The concrete should be mixed by machine in the proportions of one sack of Portland cement, 1/2 cubic feet of fine, sharp sand, and 3 cubic feet of 11/2-inch broken stone. Round, clean, washed gravel may be used instead of broken stone, but it does not make so durable a concrete. The top surface of the concrete is finished by a `:screed" made of heavy timber, the ends of which rest on the forms, or by a mechanical screed which accomplishes the same thing. The surface is finally broomed to give it a slightly corrugated texture, and the joints and edges smoothed with a trowel. Roads made of narrow, parallel concrete strips are practical only for the short, straight drive, as it is almost impossible to keep a car, on them if they are curved or if one has to back up. Another form of driveway that has been found particularly satisfactory for the small place is the granite or Belgian-block drive. These paving blocks come in two styles, the whitish ones being about 5 by 5 by 13 inches, and the black Belgian block, about 5 by 8 by 12 inches, somewhat more irregular than the former. Under ordinary conditions these can be laid without foundation, and with the joints merely filled with sand. The
great weight of the blocks holds them in place
even on sharp grades. Interesting effects can
be obtained by a judicious mixture of the two
colors and attractive patterns can be worked
out for courtyards and other places which deserve
accent and elaboration. They harmonize particularly
well with rustic architectural types such as
the Cotswold and Norman. This type of drive
is very permanent, needs little upkeep, is but
slightly more costly than penetration macadam,
gives better traction on grades than any other,
and is more interesting to look at. For a long
drive it is, perhaps, not to be recommended,
for the surface is too rough for comfort at high
speeds. At low speeds the unevenness is not at
all noticeable. DRAINAGE AND GUTTERS ©2004 garden planning dot us |
|||
|
