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→Permeable pavement sub-base and base course
#Compact each lift with a 9 ton vibratory roller, with two passes in vibratory mode and two passes in static mode, or until there is no visible movement of the aggregate.
#Compact each lift with a 9 ton vibratory roller, with two passes in vibratory mode and two passes in static mode, or until there is no visible movement of the aggregate.
#Use a plate compactor for smaller areas that the vibratory roller cannot reach.
#Use a plate compactor for smaller areas that the vibratory roller cannot reach.
===Chamber Installation===
The installation of infiltration chambers requires the placement of manifolds, the chamber components themselves, and perimeter stone. As such, the construction of infiltration chambers is a multi-faceted process.
Construction Steps:
#Install chamber manifolds to the top of the storage reservoir.
#Roll out scour fabric length-wise along the manifold.
#Lay out scour fabric where the base of the infiltration chamber is anticipated to be installed. No seams should be present where the fabric underlies the chambers.
#Align the inlet to the first chamber row with the manifold.
#Install each piece of the first chamber row, as per the manufacturer’s instructions, until the entire length of the chamber is in place. The ends of the chamber may be installed once perimeter stone is being applied to the ends of the rows, if desired, to ensure ease of inspection.
Note: where many rows of chambers are being installed, it may be advisable to construct the chamber rows piece-wise as the application of perimeter stone progresses to provide space for excavators to apply the stone from on top of the stone foundation. See the adjacent photo for an example.
#With a stone conveyor or excavator, begin placing perimeter stone. For domed chambers, place stone along the centreline of the chamber rows. Doing so will distribute stone to either side of the chamber, anchoring each side in roughly equal proportion.
#Backfill the excavated area with perimeter stone to the depth specified in the contract documents. Ensure that the depth of stone does not differ by more than 300 mm between the sides of the chamber rows.
#Once backfilling is complete, level the perimeter stone with a small dozer. Only push material in the direction parallel to the rows.
#If specified by the design, roll geotextile parallel to rows over the top of stone. Provide sufficient overlap, as specified by the manufacturer.
Key Inspection Points:
*Manifolds protrude into the storm chambers at the appropriate length, per manufacturer’s specifications.
*Scour fabric does not overlap beneath the walls of the chambers.
*Minimum distance between adjacent chambers is provided.
*Minimum depth of stone below and stone above chamber is provided.
*Depth of chamber inverts are installed correctly, relative to the elevation of the inlet, such that the storage potential of the chamber is maximized.
*Infiltration chambers are assembled as specified in the design.
*Perimeter stone extends to the excavation walls.
Mistakes to Avoid:
*Equipment on the perimeter stone – Perimeter stone should be applied with a stone conveyor or excavator from the outside of the LID footprint or on the stone foundation.
*Uneven perimeter stone – Perimeter stone must be applied such that the depth of stone on one side of the chamber is not unacceptably higher than the other. Refer to design details.
*Incorrect inlet elevation – For applications where infiltration chambers overflow into a sewer, it is important that the top of chamber is positioned at an elevation below the lowest invert of the sewer. Otherwise, only part of the chamber volume can be utilized.
==Stone choker layer==
==Stone choker layer==