PRECAST CONCRETE PAVING BLOCKS FOR SIDEWALKS
Has been made sidewalks project of an education center.
PRECAST CONCRETE PAVING BLOCKS FOR SIDEWALKS
REFERENCES
The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.
R.D. 2232 dated 16.11.1939 Technical Norms for Acceptance of Natural Stone for Construction
D.M. 14.2.1992 Technical Norms for the Execution of Castin-Place and Prestressed Concrete and for Metal Structures
Standards for Aggregates
Aggregates used for the manufacturer of precast concrete paving blocks specified hereinafter shall meet the relative applicable requirements of
SUBMITTALS
Product Data
Submit complete descriptive literature for each type of paving block proposed for use. Clearly mark the data to indicate which type and size of item the Contractor intends to provide. Provide sufficient data to show conformance to specified requirements.
a. Precast concrete paving blocks
Samples
Submit for approval by the Contracting Officer, prior to delivery to project site, the following samples:
a. Two blocks of each type of paving blocks used.
Test Reports
Submit certified test reports for the following materials:
a. Mortar
Tests for Mortar
Tests for mortar and establishing the proportions of mortar for use on the work shall be done by an approved commercial testing laboratory at the expense of the Contractor. Average compressive strength of mortar shall be not less than the requirements specified for each type of mortar.
Certificate
Submit certificate of conformance attesting that the products meet the requirements specified.
a. Precast concrete paving blocks
b. Mortar
DELIVERY AND STORAGE
Deliver paving blocks to work site in their original containers, plainly marked and labeled with producers names and brands. Protect materials from direct contact with the ground. Handle materials with care to avoid chipping and breakage.
ENVIRONMENTAL CONDITIONS
Do not lay paving blocks when the air temperature is below 4.5 degrees C and falling. Work will not be permitted with or on frozen materials. When paving blocks are set in mortar, protect newly laid work from rain, ice, or snow with weather resistive membrane for at least forty-eight (48) hours.
MATERIALS
Precast concrete paving blocks
Shall be a modular fit and shall be compatible with each other. Pavers shall be hydraulically pressed with chamfered edges.
Mortar
a. Sand: Shall be clean, free from clay organic matter and foreign substances, river type.
b. Cement: Shall be Portland Type 325 in accordance with Italian regulations.
c. Water: Shall be clean, free from oils, acids, salts, alkaline and organic matter or other foreign substances.
d. Mortar Proportions: Mortar proportion by volume and minimum compressive strength at twenty-eight (28) days shall be as follows:
MORTAR PROPORTIONS BY VOLUME
COMPRESSIVE
MAXIMUM * STRENGTH PORTLAND DAMP LOOSE 5 CM CUBES CEMENT AGGREGATE 28 DAY (KG/CM2)
(*) The damper loose aggregate should not be less than 3 times, nor more than 3 1/4 times the cementitious material used.
Concrete Base
Shall be for concrete pavement as specified in Section 03300, "Cast-In-Place Concrete".
Expansion Joints
15 mm preformed expansion joint filler shall be provided at all structures, building or wall lines, or any other appurtenances encountered as specified in Section 03300, "Cast-In-Place Concrete".
Sand Base
Sand base shall be sand base course as specified, "Aggregate and Sand Base Courses."
PAVING BLOCKS
Precast concrete pavers shall be used for all areas and sidewalks as indicated.
MIXING OF MORTAR
Mortar shall be mixed in approved mechanical mixers, except where handmixing for small batches is authorized. Hand-mixed, small batches shall be mixed in approved mixing boxes. All material except that delivered in bags of standard weight shall be measured with approved boxes before mixing. Material for mortars shall be dry-mixed until the mass assumes a uniform color, then water will be gradually added in the least possible, but sufficient amount, mixing continuously. Mixers and tools shall be carefully cleaned after each batch has been mixed. The use of mortar which has caked or has begun to harden, will not be permitted.
PAVERS
Lay pavers on concrete base or on sand base as indicated on drawings. All paving blocks laid in driveway or street crossings regardless of size, shall be laid on concrete base with mortar joints. Form the joints indicated with wooden spacers inserted temporarily to help keep spacing regular. Fill the joints as indicated. Take care to avoid dropping mortar on the slab surfaces and sponge off any drops immediately to avoid staining. Avoid cutting slabs except where necessary, support the slab well and cut with the following tools:
a. A bolster/broad bladed chisel and club hammer.
b. A power masonry saw.
c. A hydraulic slab splitter.
CLEANING
At completion of the work, clean all debris resulting from this work.