Medidas realizadas para potenciar los servicios ambientales del verde

If the Contractor uses forced air heating units, the concrete shall be kept continuously moist during the complete heating and curing period. Combustion type heaters may be used but they shall be so constructed and so placed that their combustion gases do not come in contact with surfaces of the concrete during placing and curing causing carbonation of concrete. The period of protection shall be seven days and the Contractor shall bear the cost of all heating and protection.

311.01.07 – Hot Weather Requirements

Air Temperature

When the ambient air temperature is at or above 27°C, or when there is a probability of the temperature rising to 27°C during the placing period, as forecast by the nearest official meteorological office, facilities shall be provided for protection of the concrete in place from the effects of hot and drying weather.

The concrete temperature at time of placing shall not exceed 30°C.

Fogging and evaporation protection shall be used subject to the approval by the Engineer.

311.01.08 Temperature Non-Compliance

Any concrete failing to comply with the temperature requirements shall:

• If compliant to all other Specifications, be left in place with no payment, or if in a development area, the developer shall deposit with The City an amount of money equivalent to the value of the work.

• If non-compliant in any other aspect, be replaced. • If freezing has occurred, be replaced.

Where non-compliance occurs, the test indicating non-compliance shall be held as representative of the test area.

311.01.09 – Extruded Sidewalk, Curb, and Gutter

The Contractor shall be given the option of constructing extruded sidewalk, curb, and gutter at the Unit Rate. Automatic grade and line control shall be required.

Extruded concrete shall be finished as shown in the applicable drawings, with the surface brush finished; a dense uniform surface shall be required on curb and gutter.

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311.01.10 – Monolithic Sidewalk

Monolithic sidewalks shall be constructed in one operation unless prior written approval has been granted by the duly authorized ROADS representative. If written approval is granted to construct in two separate operations, the Contractor shall install 150 mm long tie bars, made from 10M rebar, into the back of curb at 750 mm centre-to-centre. The cost of installing tie bars shall be included in the Unit Rate for Monolithic Sidewalk.

In areas where a separate sidewalk is constructed at the back of an existing curb, tie bars shall be drilled into the back of curb at 750 mm intervals. The cost of installing dowels shall be included in the Unit Rate for Separate Sidewalk.

311.01.11 – Termination

At the sole discretion of the Engineer, the placing of concrete may be suspended or terminated at any time after September 30.

311.02.00 – Site Preparation

311.02.01 – Break Out

The Contractor shall not break out any existing sidewalk and/or curb and gutter without first receiving approval from the Engineer. The designated amount of breakout shall be paid for at the Unit Rates. Any breakout exceeding the designated amount and the related

replacement shall be at the Contractor's own expense.

All break out shall end at a contraction, expansion, or surface joint. The edge of a surface mark shall be sawn to a depth of 50 mm minimum, while contraction joints may be neatly hand chiselled. All work involved in sawcutting or hand chiselling shall be included in the Unit Rates.

The broken pieces of concrete shall be properly disposed at Waste Management sites, and conform to those conditions outlined in section 302.00.00 – Earthwork within 24 hours after commencement of the break out operation.

311.02.02 – Excavation and Fill

1) General

The excavation shall be to proper grade, line, and cross-section for placing of concrete sidewalk, curb and gutter, or combined sidewalk, curb and gutter, and construction of concrete catch basins and concrete invert crossings. If the Contractor excavates below

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grade, he shall backfill with approved base gravel, compacted to the satisfaction of the Engineer at no extra cost to The City.

Excavation includes the removal and disposition of all material of whatever nature encountered, within the boundaries necessary for the preparation and construction of

concrete sidewalk, curb and gutter, or combined sidewalk, curb and gutter, catch basins, and other structures to the required cross-section, alignment, and depth shown on the plans. All unsuitable matter encountered at sub-grade level shall be removed and replaced with approved gravel fill, thoroughly compacted. See section 305.00.00 – Gravel Road and Lane Construction. The sub-grade shall provide a uniform bearing capacity over the area of the structure.

All approved loam or grass sods encountered during excavation shall be stockpiled at site for use during backfilling and lawn rehabilitation.

Under no circumstances shall any excavated material be sold or otherwise disposed of by the Contractor, Sub-Contractors, or any of their employees. Excavated material from a natural gravel base area may be used as base gravel material for fills or embankments, providing the use of such material has first been approved in writing by the Engineer.