Taylor Concrete

Part 1: General

1. Work includes furnishing and installing modular block retaining wall units to the lines and grades designated on the construction drawings and as specified herein.
2. Work includes preparing foundation soil, furnishing and installing leveling pad, unit fill and backfill to the lines and grades designated on the construction drawings.
3. Work includes furnishing and installing all related materials required for construction of the retaining wall as shown on the construction drawings.

1. Section 02246 – Geogrid soil reinforcement

1. ASTM C90 – 90 hollow load bearing masonry units
2. ASTM C140 – 75 sampling and testing concrete masonry units.
3. ASTM C145 – 85 solid load bearing concrete masonry units
4. UN-STD 1804
5. ASTM 2339 – 70
6. FHA UM – 60

1. Contractor shall check the materials upon delivery to assure that proper materials have been received.
2. Contractor shall prevent excessive mud, wet cement, epoxy, and similar materials (which may affix themselves) from coming in contact with the materials.
3. Contractor shall protect the materials from damage. Damaged material shall not be incorporated into the retaining wall structure.

1. Samples of all products used in the work of this section.
2. Latest edition of manufacturer's specifications for proposed materials, method of installation and list of material proposed for use.

1. Soil testing and inspection service for quality control testing during earth work operations will be supplied by the owner.

Part 2: Products

1. Masonry units shall be ROCKWOOD Retaining Wall Units as manufactured by Taylor Concrete Products, Inc. in accordance with ASTM – 90 and ASTM – C140.
2. Concrete wall units shall have a minimum 28 day compressive strength of 3000 psi. The concrete shall have a maximum moisture absorption of 6 to 8%.
3. Exterior dimensions may vary in accordance with ASTM C90-85. 8" Classic and all Legend units shall have a minimum of 1 sq. ft. face area each. The 6" Classic shall have a minimum of 3/4 sq. ft. face area each.
4. ROCKWOOD Classic units shall provide a minimum of 100 psf of wall face area for 6" and 8" Classic and 175 psf of wall face area for Legend. Fill which is contained within the dimensions of the units may be considered as 80% effective weight.
5. Units shall have angled sides capable of concave and convex curves.
6. Units shall be positively interlocked with ROCKWOOD's anchor bars. The Anchor Bar positively locks into the two units below.
7. The Units shall have NO pins.
8. The Anchor Bar creates an automatic setback of 1" per 8" course or 3/4" per 6" course.

1. Material conforms to UN-STD 1804, ASTM 2339-70 and FHA UM-60.

1. Material shall consist of compacted sand, gravel, crushed rock or unreinforced concrete as shown on the construction drawing. Peagravel is not recommended.

1. Fill for units shall be free draining crushed stone or course gravel, 3/8" to 3/4", with no more than 5% passing through the No. 200 sieve. Gradation of the fill shall be approved by the engineer.
2. Place recommended fill behind the retaining wall units. Pearock not recommended.

1. Material shall be site excavated soils when approved by the engineer unless otherwise specified in the drawings. Unsuitable soils for back fill (heavy clay or organic soils) shall not be used in the backfill or in the reinforced soil mass.
2. Where borrowed fill is required, contractor shall submit sample and specifications to the engineer for approval.

Part 3: Constructing the Wall

1. Contractor shall excavate to the lines and grades shown on the construction drawings. Contractor shall be careful not to disturb embankment materials behind lines shown.

1. Foundation soil shall be excavated as required for leveling pad dimension shown on the construction drawings, or as directed by the engineer.
2. Foundation soil shall be approved by the engineer to assure that the actual foundation soils conditions meet or exceed assumed design strength. Soils not meeting required strength shall be removed and replaced with acceptable material.
3. Over-excavated areas shall be filled with approved compacted backfill material.

1. Leveling pad materials shall be placed as shown on the construction drawings, upon approved foundation, to a minimum thickness of 6".
2. Material shall be compacted so as to provide a level surface on which to place the first course of units. Compaction shall be to 95% of Standard Proctor for sand or gravel type materials. For crushed rock, material shall be densely compacted.
3. Over-excavated areas shall be filled with approved compacted backfill material.
4. Leveling pad materials shall be to the depth and widths shown. Contractor may opt for using reduced depth of sands, gravel or crushed rock by using a concrete topping. Concrete shall be unreinforced and a maximum of 3" thick.

1. First course of concrete wall units shall be placed on the base leveling pad. The units shall be checked for level and alignment.
2. Ensure that units are in full contact with the base.
3. Units are placed side by side for full length of wall alignment. Alignment may be done by means of a string line or offset from the base line.
4. Sweep all excess material from the top of units and install the next course. Center the Anchor Bar over the two units below.
5. Lay up each course ensuring that the Anchor Bars are properly aligned with the units below. Pull each unit forward, away from the embankment, so the Anchor Bar prevents the units from coming any farther forward.
6. Where the wall changes elevation, units can be stepped with the grade or turned into the embankment.

1. Place ROCKWOOD Cap units centered between the two units directly below. Pull forward to desired position.
2. As required, provide permanent attachment to the wall units by using construction adhesive. Apply adhesive to top surface of unit below and place cap unit into position.

1. Follow the requirements of Section 02246, geogrid soil reinforcement.