All topsoil and vegetation, including stumps and other deleterious
matter, shall be removed from pavement areas. All wet or spongy sections
shall be removed and filled with selected material thoroughly tamped
or rolled. Fills shall be made in horizontal layers of not more than
twelve-inch lifts, each lift being thoroughly rolled with ten-ton
roller. If material is too dry to get optimum moisture, water must
be added. The roadway shall be shaped to true crown and to designed
grade and it must be unyielding when rolled with ten-ton roller. Any
soft or spongy material must be removed and replaced with suitable
material.
Not covered in these specifications. Each job dictates specific
drainage which must be installed because any pavement is no better
than its base, and drainage is basic.
A decision between these alternates must be made initially.
Rock must be excavated to have at least four inches of base; if excavation
is through good gravel naturally base requirements will differ; if
old road beds exist still different requirements will be indicated.
A. Alternate A: five-inch trap rock asphalt penetrated. On the prepared
subgrade shall be evenly spread a layer of 1 1/2 inches of trap
rock thoroughly rolled with ten-ton roller so that a resulting five-inch-thick
layer is obtained, all to true crown, line and grade. This shall be
penetrated with 1 1/2 gallons of asphalt, 85-100 penetration,
per square yard. Fill voids with one-half-inch trap rock.
B. Alternate B:
(1) Two inches crushed stone on six-inch gravel — no asphalt.
(2) Eight inches stone — no asphalt.
C. On prepared subgrade:
(1) Six inches compact thickness bank-run gravel (N. Y. State Item 42)
of such sizes as will pass through a three-inch square hole and shall
be well graded; that portion passing a one-fourth-inch screen shall
not be more than 45% by weight of the entire mass; use ten-ton roller;
two inches compact thickness 1 1/2 inches crushed stone, voids
well filled with screenings or sand; ten-ton-roller — no asphalt;
or
(2) Eight inches compact thickness in two layers rolled with ten-ton
roller; crushed stone, quarry spoil or other well graded field or
quarry stone; surface voids thoroughly filled with screenings or sand.