All materials shall comply with the following standards of quality:
A. General Requirements:
1. Portland cement:
ASTM C150 Type I, normal.
ASTM C150 Type II, moderate sulfate resistance.
2. Fine aggregate:
ASTM C33, clean sand graded between #200 and #4 sieve limits.
3. Coarse aggregate:
ASTM C33, uncoated crushed stone or washed gravel. Slag shall not be permitted.
4. Water-cement ratio:
Maximum 0.45.
5. Water:
ASTM C94.
6. Water-reducing admixture:
ASTM C494 Type A (normal) or Type D (retarder).
7. Air entraining agent:
ASTM C260
8. Premolded filler strips:
ASTM D994
9. Curing compound:
ASTM C309, Type 2 (white, pigmented)
10. Reinforcement:
ASTM A615, Grade 40.
B. Concrete Quality:
1. Ready-mixed concrete that complies with ASTM C94 shall be used for sidewalks, driveways, and driveway aprons. The concrete shall be supplied by a ready-mixed source which is approved by the Illinois Department of Transportation.
2. Concrete mix shall be designed using the following data:
a. Minimum compressive strength of: three thousand five hundred (3,500) psi at twenty eight (28) days, prior to first seasonal frost; four thousand (4,000) psi at twenty eight (28) days after the first seasonal frost.
b. Minimum of six (6) sacks of cement per cubic yard.
c. Maximum size aggregate of one inch (1").
d. Air entrainment of six percent (6%) ± one and one-half percent (11/2%).
e. Maximum slump of four inches (4").
f. Concrete shall contain a water-reducing admixture with no reduction in cement content.
C. Subgrade Preparation: Where a fill condition exists, all topsoil and unsuitable material shall be removed. Subgrade shall be rolled or tamped before granular fill is placed. Fill shall be placed in six inch (6") layers to the proper subgrade elevation and properly compacted to ninety five percent (95%) ASTM standard density. Side slopes of fill material shall not exceed one foot (1') vertical to three feet (3') horizontal. Where a cut condition exists, all topsoil and organic or unsuitable material shall be removed. Subgrade shall be removed to the proper elevation to allow sufficient width to accommodate the forms.
D. Granular Base: A granular base of a minimum thickness, as specified in this Article or as otherwise directed by the Village Engineer, shall be placed on the prepared subgrade. The base shall extend the full width of the sidewalk, driveway or driveway apron. The granular base shall consist of CA6 aggregate conforming to the Standard Specifications for Road and Bridge Construction as prepared by the Illinois Department of Transportation, Division of Highways, most recent edition.
E. Forms: Side forms shall be of lumber of not less than two inches (2") nominal thickness or steel of equal rigidity. The minimum depth of the side forms shall be equal to the required sidewalk, driveway or driveway apron thickness. No two inch by four inch (2" x 4") lumber forms shall be permitted. Forms shall be held securely in place by stakes or braces with the top edge true to line and grade. The forms for the sidewalk shall be set so that the slab will have a fall of one inch (1") vertical to four feet (4') horizontal from the edge nearest the property line toward the edge farthest from the property line, except as may be otherwise directed by the Office of Quality Control.
F. Expansion Joints: Expansion joints of the thickness specified below shall consist of a premolded filler strip with the top strip placed one-fourth inch (1/4") below the surface of the sidewalk, driveway or driveway apron.
1. One-Half Inch Thick Expansion Joints: Expansion joints one-half inch (1/2") thick shall be placed between sidewalks and all structures which extend through sidewalks, such as light standards, traffic light standards, and traffic poles. one-half inch (1/2") thick expansion joints shall also be provided at the junction of the driveway apron and the sidewalk and at the junction of the driveway apron and the curb.
2. Three-Fourths Inch Thick Expansion Joints: Expansion joints three-fourths inch (3/4") thick shall be placed at maximum intervals of fifty feet (50') in sidewalks and where specified by the Department of Quality Control. Where sidewalks are constructed adjacent to pavement or curbs that have expansion joints, the expansion joints in the sidewalk shall be placed opposite the existing expansion joints as nearly as practicable. Expansion joints shall also be placed where the sidewalk abuts existing sidewalks, between the driveway pavement and sidewalk, and between sidewalk and curbs where the sidewalk abuts a curb.
G. Placing and Finishing Concrete:
1. The Department of Quality Control shall be notified when the subgrade has been finished and is ready for inspection. A minimum of three (3) hours notice shall be given prior to placing concrete. No concrete shall be placed until the subgrade has been inspected and approved by the Department of Quality Control.
2. Materials should not be placed on ice or frozen subgrade.
3. The subgrade shall be moistened just before the concrete is placed. The concrete shall be placed in successive batches for the entire width of the slab, struck off from one-half inch (1/2") to three-fourths inch (3/4") higher than the finished slab, tamped until all voids are removed and free mortar appears on the surface, thoroughly spaded along the edges, struck off to the true grade, and to eliminate high and low spots and to embed large aggregate particles, a bull float or darby should be used immediately after strikeoff but before bleedwater accumulates on the surface. No finishing operation shall be performed on the surface of a concrete slab while bleedwater is present. After the bleedwater evaporates, the concrete shall be finished to a true and even surface with floats. Lastly, the surface shall be given final finish by brushing with a broom. The broom shall be drawn across the sidewalk, driveway or driveway apron at right-angles to the edges of the slab, with adjacent strokes slightly overlapping, producing a uniform, slightly roughened surface with parallel marks.
H. Control Joints:
1. Sidewalks: Control joints shall be constructed at right angles to the center line of the sidewalk and shall extend one-fourth (1/4) the depth of the sidewalk. They shall not be less than one-eighth inch (1/8") nor more than one-fourth inch (1/4") in width, and shall be edged with an edging tool having a one-fourth inch (1/4") radius. All slabs shall be five feet (5') long on any one side, unless otherwise ordered by the Director of Quality Control.
2. Driveways: Control joints shall be constructed in conformance with the American Concrete Institute (ACI) Standards and Practices, as amended, unless otherwise ordered by the Director of Quality Control.
3. Driveway Aprons: Control joints shall be constructed so as to divide the driveway apron into sections which are approximately square with no side longer than fifteen feet (15'). The control joints shall be not less than one-eighth inch (1/8") nor more than one-fourth inch (1/4") in width, and shall be edged with an edging tool having a one-fourth inch (1/4") radius. The minimum depth shall be one and one-fourth inches (11/4").
I. Protection from Low Temperatures: If concrete is placed after the first seasonal frost, concrete shall be protected from freezing in accordance with the "Recommended Practice for Cold-Weather Concreting" (ACI 306). Air-entrained concrete shall not be allowed to freeze and thaw in a saturated condition prior to developing the required design compressive strength (ACI 308). The developer or installer/contractor shall be responsible for all concrete damaged by low temperatures, and any damaged concrete shall be removed and replaced by the developer or installer/contractor at the developer or installer/contractor's expense.
J. Curing:
1. After finishing the concrete, in accordance with subsection G above, all sidewalks, driveways and driveway aprons shall be cured, in addition to the curing requirements set forth in subsection J2 below, by one of the following methods:
a. Burlap shall be placed on the finished surface, saturated with water and covered with an impermeable covering.
b. Polyethylene sheeting shall be placed as soon as the concrete has sufficiently hardened to prevent marring of the surface. The surface of the concrete shall be wet immediately before the sheeting is placed. The edges of the sheeting shall be weighted securely with a continuous windrow of earth or any other means satisfactory to the Department of Quality Control to provide an airtight cover.
c. Liquid-membrane-forming/curing compound shall be applied per ASTM C309 immediately after broom finish.
2. A minimum thirty (30) day drying period after seven (7) days of moist curing, if concrete is placed in the fall and will be exposed to freeze-thaw cycles and deicers when saturated, is required. When temperatures fall to near forty degrees (40°) Fahrenheit, a fourteen (14) day curing period may be necessary when using Type I, normal cement. The required curing period can be reduced to seven (7) days by using a Type III high-early-strength cement or a higher cement content in the concrete.
Any of the three (3) curing methods set forth in subsection J1 above must remain in place for not less than six (6) days.
K. Backfill: After the concrete has been cured, forms shall be removed and the space near the edges of the sidewalk, driveway or driveway apron shall be backfilled to the required elevation with material approved by the Department of Quality Control. The material shall then be compacted until firm and the surface evenly graded.
L. Disposal of Surplus Material: Surplus or waste material resulting from the sidewalk, driveway or driveway apron construction shall be disposed of by the developer, installer/contractor or property owner.
M. Control of Materials: The developer or installer/contractor shall, when requested by the Village and at the developer or installer/contractor's expense, have a commercial testing laboratory prepare and test samples of delivered concrete. One set of tests shall be taken for the first twenty five (25) cubic yards, or fraction thereof, and one set of tests shall be taken for each additional fifty (50) cubic yards. A set of tests shall consist of four (4) standard cylinders (2 shall be broken at 7 days and 2 shall be broken at 28 days), one slump test and one air content test. The laboratory shall perform tests in accordance with recognized ASTM standards and shall submit written reports of such tests to the Village Engineer for review.
N. Enforcement and Remedies: All construction in accordance with this Article shall be subject to the terms and remedies contained in Section 6-1-8 of the Code. (Ord. 94-10-44)