PART 3 EXECUTION
Verify locations of utilities and existing structures prior to excavation.
Examine the Project site and evaluate conditions where the ReCon retaining wall will be constructed. Notify the proper supervising authority in writing of any conditions that may interfere with the proper construction of the ReCon wall or delay completion.
Promptly notify the wall design engineer of site conditions which may affect wall performance, soil conditions observed other than those assumed, or other conditions that may require a reevaluation of the wall design.
Contractor shall excavate to the lines and grades shown on the construction drawings. The contractor shall be careful not to disturb base beyond the lines indicated.
Foundation soil shall be excavated as required for footing or base / leveling pad dimensions shown on the construction drawings, or as directed by the wall engineer.
Over-excavated areas shall be filled with suitable base or backfill material and compacted to 95% standard proctor.
FOUNDATION SOILS PREPARATION
Foundation soil shall be evaluated by a Geotechnical Engineer or Owner’s Representative to ensure that the bearing soils meet or exceed the design conditions or assumptions.
Compact foundation soil zone to 95% standard proctor prior to installing base / leveling pad.
BASE / LEVELING PAD
Base shall be located as indicated on the construction drawings and shall have a minimum thickness of 6 inches.
Width of the base pad must extend a minimum of 6 inches in front and 6 inches in back of the ReCon base unit footprint.
Base material shall be compacted so as to provide a smooth, hard surface on which to place the first course of units. NOTE: (reference 3.5 UNIT INSTALLATION)
Compact base / leveling pad material with mechanical plate compactors to 95% of standard proctor.
Prepared base to ensure full contact of the wall unit with base material and there will be no voids beneath or between units.
Contractor may elect to substitute a portion of the specified granular base materials with a lean, unreinforced concrete topping.
When a reinforced footing is required by the construction drawings, it shall be located below the frost line.
Units shall be placed in full contact with base / leveling pad material.
Check units for level from side-to-side and maintain unit batter front-to-back.
Place unit faces in contact end to end and avoid any gaps one-half inch or greater.
Fill and compact fill to grade in front of embedded units prior to compaction behind the wall units.
Fill voids between ReCon units with 3/4” clean crushed rock to a distance of one foot behind the unit depth unless otherwise instructed in the Construction Drawings.
Sweep and clean the top of each course before setting additional courses.
Lay each successive course making sure that the bottom recess is in full contact with the unit locators of the course below. Pull unit forward as far as possible.
Check and maintain level and wall batter by use of shims when necessary.
Follow ReCon recommended procedures to maintain acceptable running bond when constructing curved walls and / or corners. Build in accordance with Construction Drawings or ReCon Construction Drawing Details.
Install geosynthetic reinforcement in accordance with manufacturer's recommendations and the Construction Drawings.
Locate geosynthetic reinforcement at elevations and to the lengths shown on the Construction Drawings.
Prior to installation of geosynthetic reinforcement, level and compact backfill material to the level of the reinforcement layer.
Reinforcement design strength direction must be oriented perpendicular to wall face.
Position reinforcement on ReCon units to within 2” of the front exposed face. Hold in place by installing the next course of units.
Remove all wrinkles or folds in reinforcement by pulling taut prior to backfill placement. Secure using soil staples, stakes or hand tension until reinforcement is covered with sufficient fill to maintain tensioned position.
Reinforcements shall be continuous throughout the embedment length. Splicing along reinforcement strength direction is not allowed.
Position reinforcement sections side-by-side to provide 100% coverage along wall face.
Where curved wall sections cause overlap areas in reinforcement, maintain at least 3” of soil between layers where overlap occurs.