Stanton_Ave_-_McCandless_Ave_Addendum_1.pdf

McCandless Avenue Stair Replacement – Special Provisions – Addendum 1 - 6-29-2022

1. ITEM 9000-0002 CLASS AAA CEMENT CONCRETE MODIFIED

2. ITEM 9000-0006 PRECAST CONCRETE

3. ITEM 9000-0011 PRECAST CONCRETE LAGGING

ITEM 9000-0002 CLASS AAA CEMENT CONCRETE MODIFIED

In accordance with Section 1001 except as follows:

1001.1 DESCRIPTION –

This work is construction of all cast-in-place components as indicated.

1001.2 MATERIAL –

(a) Cement Concrete. Class AAA Cement Concrete per Section 704 except as follows:

1. Cement – Section 701, except use white Portland cement containing no more than 0.50% by weight of iron oxide.

Do not add fly ash or ground granulated blast furnace slag to concrete.

2. Fine Aggregate – Section 703.1, Type A, except add the following:

Provide white fine aggregate, from an approved source, of either crushed white marble, white limestone, or calcite. Provide aggregate that is clean, washed and free from dirt or any discoloring matter not containing more than 0.75% of ferric oxide.

3. Coarse Aggregate, Type A – Section 703.2 except add the following:

Use No. 8 Coarse Aggregate. Use only light colored crushed stone or aggregate with at least three faces resulting from fracture. Do not use slag.

4. Water – Section 720.1 except add the following:

Potable and free from iron or other impurities which may cause staining.

5. Admixtures – Section 711.3 except add the following:

Use only those admixtures that do not discolor the white cement concrete. Obtain written assurance from the manufacturer that the admixture does not cause staining.

(b) Reinforcement Steel. Use epoxy coated reinforcement bars or welded wire fabric per Section 709.

(c) Protective Coating. Use boiled linseed oil per Section 1019.

(d) Joint Material. Use expansion joint filler and asphalt rubber sealing compound per Section 705.

1001.3 CONSTRUCTION – In accordance with Section 1001.3 and 1002.3 and as follows:

(a) Section 1001.3(a)1. Add the following:

Use only form release oil that will not contribute to the discoloration of the white cement concrete. Obtain written assurance from the manufacture that the product does not cause discoloration.

(b) Section 1001.3(j). Add the following:

Use clean equipment for batching and mixing to prevent contamination by materials which may cause discoloration. Cement bins, weigh hoppers and mixers are to be free of loose gray cement. Use only form release oil that will not discolor the white cement concrete.

(c) Section 1001.3(p)3a. Add the following:

Use only white, liquid membrane-forming curing compound. Cover barrier with white polyethylene sheeting after applying curing compound. Until forms are removed, protect exposed concrete by the water cure method using only new burlap that is free of sizing or any substance that will cause staining. Thoroughly rinse the new burlap in water to remove soluble substances before placing on concrete surfaces.

(d) Section 1001.3(t). Add the following:

Apply boiled linseed oil per Section 1019 to all cast-in-place walking surfaces.

1001.4 MEASUREMENT AND PAYMENT – In accordance with Section 1001.4 and as follows:

Epoxy coated reinforcement bars, welded wire fabric, joint material and sealer, and protective coating are incidental to this item.

END OF SPECIAL PROVISION

ITEM 9000-0006 PRECAST CONCRETE

This item is for the precast components as indicated, including the optional stair support caps. If the Contractor elects to precast the stair support caps, the quantity of Class AAA Cement Concrete Modified shall be reduced accordingly.

In accordance with Section 714 and as follows:

714.1 GENERAL REQUIREMENTS –

(b) Shop Drawings – Add the following:

Shop drawings and supporting calculations shall be submitted to the City for review and approval prior to fabrication.

Shop drawings shall include all connections of the precast concrete components to cast-in-place components.

Shop drawings must indicate that existing dimensions that relate to the affected work have been field verified before shop drawings can be approved.

714.2 PRECAST CONCRETE UNITS – Add the following:

Stairs Deck Panels Stair Support Caps

714.3 MATERIAL – Add the following:

Cement Concrete. Class AAA Cement Concrete per Section 704 except as follows:

1. Cement – Section 701, except use white Portland cement containing no more than 0.50% by weight of iron oxide.

Do not add fly ash or ground granulated blast furnace slag to concrete.

2. Fine Aggregate – Section 703.1, Type A, except add the following:

Provide white fine aggregate, from an approved source, of either crushed white marble, white limestone, or calcite. Provide aggregate that is clean, washed and free from dirt or any discoloring matter not containing more than 0.75% of ferric oxide.

3. Coarse Aggregate, Type A – Section 703.2 except add the following:

Use No. 8 Coarse Aggregate. Use only light colored crushed stone or aggregate with at least three faces resulting from fracture. Do not use slag.

4. Water – Section 720.1 except add the following:

Potable and free from iron or other impurities which may cause staining.

5. Admixtures – Section 711.3 except add the following:

Use only those admixtures that do not discolor the white cement concrete. Obtain written assurance from the manufacturer that the admixture does not cause staining.

6. Use normal weight concrete only.

7. Use minimum 28-day compressive strength of 4,000 psi.

Reinforcement Steel. Use epoxy coated or galvanized reinforcement bars or welded wire fabric per Section 709.

714.7 CONCRETE – Add the following:

Use clean equipment for batching and mixing to prevent contamination by materials which may cause discoloration. Cement bins, weigh hoppers and mixers are to be free of loose gray cement. Use only form release oil that will not discolor the white cement concrete.

Apply a broom finish to all walking surfaces of the precast components.

Include a non-slip tread for each step.

Include threaded inserts as indicated for the attachment of the railing posts.

Grout used to fill lifting loop holes or for patching of the precast units should match the color of the cured precast concrete as closely as possible. Submit a sample of cured grout to the Representative for acceptance prior to placing on the completed structure.

714.8 CURING AND PROTECTIVE COATING – Add the following:

(a) Curing. Add the following:

Use only form release oil that will not contribute to the discoloration of the white cement concrete. Obtain written assurance from the manufacture that the product does not cause discoloration.

(b) Protective Coating. Add the following:

Apply boiled linseed oil to all precast walking surfaces. Anti-graffiti coating to be applied to all exposed surfaces other than walking surfaces per item 9000-0001.

MEASUREMENT AND PAYMENT – Lump Sum (LS)

Includes delivery and erection.

ITEM 9000-0011 PRECAST CONCRETE LAGGING

This item is for fabricating and installing precast concrete lagging.

In accordance with Section 714 and as follows:

714.1 GENERAL REQUIREMENTS –

(b) Shop Drawings – Add the following:

Shop drawings and supporting calculations shall be submitted to the City for review and approval prior to fabrication. All design calculations submitted to the City must be sealed and signed by a professional engineer registered in the Commonwealth of Pennsylvania.

Shop drawings shall include all connections of the precast concrete lagging to cast-in-place and steel components.

Shop drawings must indicate that existing dimensions that relate to the affected work have been field verified before shop drawings can be approved.

Provide additional field survey of lagging supports in order to assure level construction.

714.2 PRECAST CONCRETE UNITS – Add the following:

Lagging Panels

714.3 MATERIAL – Add the following:

Cement Concrete. Class AAA Cement Concrete per Section 704 except as follows:

1. Cement – Section 701, except use white Portland cement containing no more than 0.50% by weight of iron oxide.

Do not add fly ash or ground granulated blast furnace slag to concrete.

2. Fine Aggregate – Section 703.1, Type A, except add the following:

Provide white fine aggregate, from an approved source, of either crushed white marble, white limestone, or calcite. Provide aggregate that is clean, washed and free from dirt or any discoloring matter not containing more than 0.75% of ferric oxide.

3. Coarse Aggregate, Type A – Section 703.2 except add the following:

Use No. 8 Coarse Aggregate. Use only light colored crushed stone or aggregate with at least three faces resulting from fracture. Do not use slag.

4. Water – Section 720.1 except add the following:

Potable and free from iron or other impurities which may cause staining.

5. Admixtures – Section 711.3 except add the following:

Use only those admixtures that do not discolor the white cement concrete. Obtain written assurance from the manufacturer that the admixture does not cause staining.

6. Use normal weight concrete only.

7. Use minimum 28-day compressive strength of 4,000 psi.

Reinforcement Steel. Use epoxy coated or galvanized reinforcement bars or welded wire fabric per Section 709.

Plain Elastomeric Bearing Pads. Provide plain elastomeric bearing pads for support of lagging panels in accordance with Section 1113.

714.7 CONCRETE – Add the following:

Use clean equipment for batching and mixing to prevent contamination by materials which may cause discoloration. Cement bins, weigh hoppers and mixers are to be free of loose gray cement. Use only form release oil that will not discolor the white cement concrete.

Grout used to fill lifting loop holes or for patching of the precast lagging should match the color of the cured precast concrete as closely as possible. Submit a sample of cured grout to the Representative for acceptance prior to placing on the completed structure.

714.8 CURING AND PROTECTIVE COATING – Add the following:

(a) Curing. Add the following:

Use only form release oil that will not contribute to the discoloration of the white cement concrete. Obtain written assurance from the manufacture that the product does not cause discoloration.

(b) Protective Coating. Add the following:

Anti-graffiti coating to be applied to all exposed surfaces per Item 9000-0001.

714.11 TRANSPORTATION – Add the following:

Place lagging level and as indicated. Provide uniform appearance to exterior face of wall. Repair or replace any damages resulting from transport or installation to the satisfaction of the Engineer at no cost to the Department.

MEASUREMENT AND PAYMENT – Measured per square foot for the total surface area of the entire front face of the precast concrete lagging panels.

Includes delivery and erection.