CURBS, GUTTERS, SIDEWALKS, AND DRIVEWAY APPROACHES CONSTRUCTED UNDER CITY PERMITS
DETAIL SPECIFICATIONS NO. 20A
2001.1A Construction between the lip of the gutter and the front property line under City permit and inspection shall be in conformity with these specifications, provided that with the approval of the Director of Public Works, special provisions attached to approved building plans, established good engineering practice, or special instructions given at the job site by the Engineering Inspector shall prevail when a conflict with these specifications is determined. Work not done according to these specifications, or work which undergoes failure at any time up to six months following installation when, in the judgment of the Director of Public Works said failure is the result of non-compliance with these specifications, shall be replaced by the permittee, or by the City at the permittee’s expense.
2002.1A Portland Cement Concrete (hereinafter referred to as concrete) shall be five (5) sack, 1½” maximum aggregate and shall conform in all other particulars to City of Berkeley Detail Specification No. 50 or the current edition of Standard Specifications of the State of California of Transportation (hereinafter referred to as State Specs) except that the concrete whose slump exceeds 4” at the work site is prohibited in any case.
2002.2A Paving Brick and Paving Tile (pavers) shall have a surface which is sufficiently abrasive to insure pedestrian safety. A sample of the paver must be submitted to and approved by the Public Works Department prior to the start of construction.
2002.3A Cement Mortar shall consist of three (3) parts washed masonry sand, free of organic material, mixed with one (1) part of Portland cement. About ¼ part of lime or fire clay may be added if desired.
2002.4A Reinforcing Steel shall be ½” diameter (#4) deformed bars unless an alternate is specifically approved by the Engineering Inspector and shall conform to the current applicable State Specs.
2002.5A Concrete Additives other than 1½ pound of lampblack per cubic yard (required in concrete for standard finish sidewalks, widened sidewalks and driveways) must be approved in advance by the Engineering Inspector. All additives, other than color additives, must be added at the batch plant. Rapid curing agents, such as NaCl or CaCl may not exceed 1% in any case and are strictly prohibited from concrete with reinforcing steel.
2002.6A Prohibited Material. The installation of any material other than standard finished concrete or soil in the area between the front property line and the curb is prohibited unless specifically authorized by the Director of Public Works or his representative.
2002.7A Untreated Base shall be granular, non-cohesive, well graded crusher run, ¾” to 1½” maximum aggregate. Bay sand, quarry wastes, or other suitable material may be used in place of crusher run if approved by the Engineering Inspector.
2002.8A Curing Compound shall conform to the current State Specs and when used, shall be sprayed on the concrete within one hour after finishing at the rate of one (1) gallon per two hundred (200) square feet.
2003.1A Sidewalks shall have a minimum thickness of 3½” of concrete or other approved paving material. Sidewalk widths shall be those designated in the counter maps of the Department of Public Works, or as directed by the Engineering Inspector at the job site. Sidewalk cross slope shall be not less than 1/8” per lineal foot no more than ¾” per lineal foot unless authorized by the Engineering Inspector. The optimum cross slope is ¼” per lineal foot.
2003.2A Widened Sidewalk must be authorized by the Director of Public Works or his representative before installation is allowed. In those cases where the widened sidewalk is between the curb and the front of the established sidewalk line, the installation of one or more tree wells or tree well knockouts may be required by the city of Berkeley Forestry Supervisor. He should be contacted prior to the start of construction so that the number, location and size of the tree wells can be determined. All widened sidewalk shall be 3½” minimum thickness and shall not exceed 1½” per lineal foot cross slope unless authorized by the Engineering Inspector.
2003.3A Driveways. All driveway approaches shall be 6” minimum thickness of concrete. All driveway approaches which, in the opinion of the Director of Public Works or his representative, will receive sufficiently heavy truck use to qualify as a “commercial” driveway shall have ½” (#4) reinforcing bars on 18” centers, each way, embedded in the concrete 2” – 3” above the base. Driveway approach widths and dimensions shall conform to the Department of Public Works Specifications contained in the brochure, “Parking, Loading, Driveway and Access Standards” and Standard Plan #2641 or #3134 as applicable. The driveway apron shall be constructed in such a way that a minimum 6” water barrier is maintained between the gutter flowline and the front sidewalk line (or within 4 feet of the gutter flow line where no sidewalk exists) unless specifically exempted by the Engineering Inspector.
2003.4A Curb and Gutter shall be standard vertical curb and monolithic 24” wide gutter as shown on Standard Plan #2541. Curb shall be standard vertical curb as shown on Standard Plan #1701. Where adjacent curb or curb and gutter is non-standard, or where authorized by the Engineering Inspector, an alternative design may be allowed provided permission is sought and obtained prior to the start of construction.
2003.5A Concrete Finish. Sidewalks and driveways shall be finished using a wood float applied with circular motion or, where the street slope or driveway slope is less than one (1) foot in 8 feet, with a medium soft broom stroke in a direction perpendicular to the curb. Where the existing adjacent sidewalk finish is still sufficiently visible to determine the method used, every effort should be made to match it as closely as possible except that steel trowel or slick finish concrete is strictly prohibited in any case. Curb and/or gutter shall be steel troweled and lightly brushed to remove the trowel marks. Any finish other than these standard concrete finishes must be approved by the Engineering Inspector prior to the start of work.
2003.6A Control Joints or weakened plan joints approximately 1/5 the thickness of the concrete in depth and ¼” maximum width shall be placed using standard commercially available tools or control joint filler material as directed by the Engineering Inspector and in conformity with the following standards: transversely (perpendicular to the curb) about every 10 - 12 feet in all sidewalks, widened be installed at edge of driveways, curbs and/or gutters. Additional transverse joints should be installed at edge of driveways where the thickness changes, at tree well corners, at beginning and end of curb returns and at projecting corners of existing sidewalk or other structures where contraction cracks are likely to occur. Longitudinal (parallel to curb) control joints shall be installed in driveways in alignment with front and back edges of sidewalk, in sidewalks, widened sidewalks and driveways to align with the back of curb, when curb and flat work are poured monolithically (together) and along back of sidewalk at entry walks. On long continuous sidewalk pours or in known earth movement areas, control joint filler material may be required by the Engineering Inspector in addition to the regular control joints. Wherever possible, control joints shall be placed to coincide or align with score marks.
2003.7A Score Lines shall conform to the same pattern established in the existing adjoining sidewalk or driveway. Where there are conflicting score patterns on the block, or where the entire frontage is being replaced, the Engineering Inspector may approve an alternate score pattern.
2003.8A Paving Brick or paving tile (pavers) shall be embedded in ½” thick minimum mortar over a minimum 3” thick concrete base when installed in the sidewalk (6” concrete base in driveways). The mortar joints between bricks shall be finished flush or only slightly depressed below the pavers’ surface. In residential areas, or low pedestrian use areas, alternate installation methods may be approved by the Engineering Inspector for paver installation in the parking strip or behind the sidewalk.
2004.1A Subgrades shall be compact and of an even grade. Soft spots shall be removed and backfilled with Untreated Base as directed by the Engineering Inspector. Subgrade shall be thoroughly wet prior to placing concrete.
2004.2A Base Construction, when required by the Engineering Inspector, shall consist of 2” minimum thickness of Untreated Base (see Materials). The base shall be compacted to an even grade with no pockets or irregularities and thoroughly wet prior to the placing of concrete.
2004.3A Existing Concrete curbs, gutters, sidewalks and driveways shall be saw cut to a minimum depth of 1½” (1” for sidewalks) along the nearest score line adjacent to the area being replaced where an existing control, expansion or cold joint does not exist to provide a neat edge from which to finish the new work. The existing flat work shall be under cut 2” minimum vertically horizontally to provide a “key” to decrease the possibility of future sidewalk lifting. Under certain conditions, dowelling may be required as described in Standard Specification #208.
2004.4A Forms shall be set at the correct line and grade in compliance with the Design Specifications above and in accordance with good Engineering practice.
WARNING: Concrete shall not be placed until forms have been inspected and approved by the Engineering Inspector, or when atmospheric temperature is less than 36° F, or when rainfall is imminent. The permittee is advised to have on hand plastic sheeting, ready to cover concrete surface, when working in threatening weather.
2004.5A Finishing Methods. For sidewalk or driveway construction, immediately after the concrete is placed and screened, concrete shall be bull floated or wood floated, edged and control jointed. When concrete has set long enough to evaporate all bleed water from the surface (2 – 4 hours after placement, depending on weather), the second floating may commence (the sprinkling of dry cement to absorb excess surface water is prohibited). The second floating should be done with a wood or metal alloy float. If a broom finish is desired, a third floating with a steel trowel is recommended. After completion of the floating operations, the score lines should be installed, using a straight board and/or snapped line as a guide, the edges and control joins re-done if necessary and the final surface finish installed.
For curb and gutter construction, the concrete, immediately after placing in the forms, should be rodded (rapid up and down movement with a piece of reinforcing steel or other rod in wet concrete) and the forms struck with a hammer to distribute and compact the loose concrete. The top should then be screeded, edged and control jointed.
As soon as concrete has gained sufficient rigidity to remain in place without slumping (24 hours after placement, depending on weather), the front curb form shall be removed and the curb face control jointed, steel troweled and brushed
Special finishes, such as exposed aggregate, colored concrete, patterned broom, etc., shall be finished according to standard construction methods, which shall be discussed with and approved by the Engineering Inspector prior to the placing of concrete.
Curing compound should be sprayed on sidewalks and driveways when the outside temperature exceeds 70°, or if other atmospheric conditions make such treatment advisable.
2004.6A Form Removal and Clean Up. Forms, other than curb face forms, shall be removed no sooner than 12 hours after finishing has been completed adjacent to new concrete created by the installation and removal of forms shall be filled to the proper grade with soil or other suitable material. Any street paving removed to facilitate the construction of a curb, gutter or driveway shall be replaced by repaving the open area with asphalt concrete in accordance with standard City of Berkeley specifications or as directed by the Engineering Inspector. Any defaced concrete shall be repaired within 24 hours of the final finishing operation by rubbing with a stone and water and rebrushing or other method approved by the Engineering Inspector. If, in the inspector’s opinion, the defacement is too severe to be repaired, the concrete shall be saw cut along the nearest score line to a minimum depth of 1½”, removed and replaced with new concrete. All tools, barricades, debris, forms, etc., shall be removed from the site before traffic is allowed through the work area.
2004.7A Protection of Work. The installer shall protect his work in accordance with good engineering practice. Normally, new concrete should not be opened to foot traffic for 24 to 72 hours, nor to vehicular traffic within 72 hours, but in no case will concrete be opened either to pedestrian or vehicular traffic in less than 24 hours after finishing. The permittee or his installing agent is responsible for the protection of the work. The use of suitable signs, barricades and lights, and the maintenance of pedestrian and vehicular safety is required.
Engineering Permit Information