A. Specifications: The installation of all new or reconstructed sidewalks and curbs in the residential districts of the city shall be constructed and installed in the following manner:
1. All curbs shall consist of integral curb and gutter with an apron eighteen inches (18") wide.
2. The outside edge of the curb, back face to back face, exclusive of the apron, shall conform to the established street width as approved by the city council.
3. All new sidewalks shall be a minimum of five feet (5') in width and shall be placed adjacent to the curb. However, where a block has an established sidewalk pattern with a boulevard, new sidewalks in that block shall conform to such pattern unless all existing sidewalk is replaced to match new construction. (Ord. 389, 8-16-2004)
4. At all corners of streets and avenues, the curbs shall be curved with a twenty foot (20') radius, and must be ADA compliant. (Ord. 389, 8-16-2004; amd. 2015 Code)
B. Concrete Crosswalks: No concrete crosswalks shall be installed across the streets or avenues.
C. Cost Of Crosswalks: The city shall pay the cost and expense of installing crosswalks across the alleys within such residential districts.
D. Grade, Plans And Specifications: All sidewalks and curbs shall be installed in accordance with established grades and the plans and specifications on file at city hall and as provided by the public works director.
E. Placement Of New Curb And Sidewalks: New curb and sidewalks shall be placed on undisturbed natural soil cut to grade or upon fill material compacted to ninety five percent (95%) density per AASHO T-180 and to the satisfaction of the public works director. No sand or loose gravel bed shall be allowed.
F. Minimum Thickness; Slope: Sidewalks shall be a minimum thickness of four inches (4") and where installed adjacent to the curb, the sidewalk shall have a uniform slope of one- fourth inch (1/4") per foot toward the street. The top of the curb shall not extend above the sidewalk.
G. Expansion Joints: For each fifty (50) linear feet of sidewalk, one expansion joint shall be provided, using one- half inch (1/2") bituminous fiber material, and one transverse score shall be installed for each five feet (5') with such scores extending one inch (1") below the surface. Expansion joint fillers shall be placed adjacent to any existing curb, sidewalk or structure.
H. Finish: All curb, gutter and sidewalks shall be installed continuously, in full thickness, using a transverse broom finish as work progresses.
I. Materials:
1. Materials for curb, gutter and sidewalks shall consist of dirt free sand and gravel with coarse aggregate not larger than three-fourths inch (3/4") and six (6) sacks of portland cement per cubic yard of concrete. Air entrained concrete shall be used unless otherwise specified and in all cases, minimum compression strength shall be three thousand five hundred (3,500) pounds per square inch in twenty eight (28) days, maximum slump of three inches (3"), and not more than six (6) gallons of water per sack of cement. Use of ready mix concrete meeting these requirements is preferred.
2. The public works director will determine, by trial, the amount of air entraining admixture required to produce concrete having the specified air content and this amount shall not be varied except as directed by the public works director. Required air content shall generally contain six percent (6%) air, plus or minus one percent (±1%).
J. Vehicular Travel Lanes: Six inch (6") concrete sidewalk construction shall be required across all vehicular travel lanes, such as alleys, public or private driveways, etc. Subbase shall be well compacted by wetting, tamping or rolling.
K. Frames:
1. Wood: All wood forms for straight work shall be of two inch (2") surfaced lumber free from warp; forms for curved work shall be made of suitable material bent to the required radius and sufficiently heavy to hold its shape during the progress of placing concrete.
2. Steel: An approved make of steel forms may be used in place of the wooden forms specified above. Forms shall have a depth equal to the thickness of the concrete to be placed against them.
3. Built Up, Battered, Bent, Twisted Or Broken Forms: Built up, battered, bent, twisted or broken forms shall be removed from the work. All forms shall be cleaned and oiled each time they are used.
L. Setting Of Forms: Forms shall be set upon the compacted subgrade and to exact grade and alignment and so constructed as to resist without springing or settlement the pressure of the concrete and the operation of the finishing machines, and so constructed that they may be removed without injuring the concrete.
M. Placement Of Concrete:
1. Concrete shall be placed on an even, moist subgrade, but there shall be no pools of water standing. If the subgrade is readily dry, it shall be sprinkled with as much water as it will absorb readily and as the public works director may direct.
2. Concrete shall not be placed on a frozen subgrade, and shall not be placed when the temperature is forty degrees Fahrenheit (40°F) or less and falling, unless upon written permission from the public works director, and provided all materials are heated in such a manner that the mixture is delivered at a temperature of at least sixty degrees Fahrenheit (60°F) and provided the concrete is protected and held at a minimum temperature of fifty five degrees Fahrenheit (55°F) for a period of three (3) days. Permission to proceed with cold weather concreting shall not relieve the installer of responsibility for obtaining satisfactory results. Unsatisfactory concrete shall be removed and replaced by installer.
3. Concrete slabs laid on the ground, or other similar concrete construction, may be protected against freezing by insulation with a thick layer of straw or other acceptable material, if approved by the public works director. No concrete shall be placed on frozen ground.
4. The use of salt or other compounds to prevent concrete from freezing will not be permitted.
N. Finished Walks And Driveways: Concrete walks and driveways shall be screened transversely with a straight edge and, when the concrete has reached proper elevation, floated with a wood float to a true and uniform plane with no coarse aggregate showing. All edges and joints shall be rounded with an edging tool. The use of mortar topping or drier will not be permitted. Concrete sidewalks requiring a slightly roughened surface shall be floated to a true, uniform surface and broomed. Excessive troweling is to be avoided as it tends to bring too much water and fine material to the top, forming a chalky surface. Edges and joints of sidewalks shall be edged with an edging tool having a radius of not less than one-fourth inch (1/4").
O. Curb And Gutter Finish: Curb and gutter may be finished by the use of a special shaped trowel, or curb and gutter machine which will shape the entire upper surfaces in accordance with the dimensions and shape specified on the drawing. The top and face of the curb and also the top of the apron on combined curb and gutter must be finished true to line and grade and without any irregularities of surface noticeable to the eye. Should any portion of the gutter hold water to a depth of more than one-fourth inch (1/4"), or should any portion of the surface or face of the curb or gutter depart more than one-fourth inch (1/4") from a straight edge ten feet (10') in length placed on the same parallel to the centerline of the street, or should any part of the exposed surfaces present a wavy appearance, the same will be sufficient cause for rejection of that portion of the work, and the public works director shall have the right to cause the work to stop at any time, if the work being produced is not satisfactory to him. Joints and top edge of curb shall be rounded to a radius of one-fourth inch to one-half inch (1/4" - 1/2"), but front edge of apron shall be left with a sharp edge to prevent an area for water to enter between gutter and pavement.
P. Curing Of Fresh Cement:
1. Fresh concrete shall be adequately protected from heavy rains and physical damage. Rapid evaporation of water, with resultant drying out of surfaces shall be prevented. The curing process shall be commenced as soon after placing of the concrete as can be done without injury to the concrete surface. When pending or spraying methods of curing are used, the exposed concrete surfaces shall be protected with wet burlap until the concrete surface has set sufficiently to prevent damage from the direct application of water. The burlap shall be applied as soon after the placing of concrete as possible and without marring the surface of the concrete. All concrete shall be kept wet for a period of three (3) days by ponding with water, application of a water saturated covering or by other approved methods which will keep all surfaces continuously wet. Wood forms left in place during curing shall be kept wet.
2. The use of impervious membrane coatings for curing of concrete walks and similar exposed surfaces will be permitted only upon specific approval of the public works director, complete and uniform coverage at the rate of two hundred (200) square feet per gallon is required. Membrane coatings shall not be used on surfaces where discoloration is objectionable, on surfaces which are to be painted, or on concrete base which is to be overlaid or abutted with an asphaltic surface course.
3. The freshly finished walk shall be protected from hot sun and drying winds until it can be sprinkled or covered as above specified. The concrete surface must not be damaged or pitted by rain drops and the installer shall provide and use, when necessary, sufficient tarpaulins or waterproof paper.
4. In any case, the installer shall be responsible for the adequate curing of all concrete during the entire curing period. Concrete which, in the opinion of the public works director, shows conclusive evidence of improper and inadequate curing, may be rejected.
5. The installer shall erect and maintain suitable barriers to protect the work from traffic and any section damaged from traffic or other causes occurring prior to its acceptance shall be repaired or replaced by the installer in a manner satisfactory to the public works director.
Q. Removal Of Forms: Forms shall be removed not less than twenty four (24) hours after concrete has been placed. Removal of forms shall be carefully done without damage to the concrete. Prying against green concrete shall not be permitted. Minor defects shall be repaired with a mortar of one part cement and two (2) parts of fine aggregate. After the concrete has sufficiently cured, the spaces about the walk, curb and gutter shall be backfilled.
R. Curb And Gutter Driveway Depressions: Curb and gutter driveway depressions shall maintain a flow line of two inches (2") in depth, and concrete thickness for driveways within city property shall be a minimum of six inches (6"). New driveway depressions installed in existing standard curb and gutter shall be under the direction of the public works director and shall require a building application. (Ord. 389, 8-16-2004)