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Line 1: − + − + − + − *''d'' = Stone bed depth (m) Line 14:
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→To calculate the total depth of the stone reservoir (all graded layers)
The following calculation is used to size the stone storage bed (reservoir) used as a base course. It is assumed that the footprint of the stone bed will be equal to the footprint of the pavement. The following equations are taken from the ICPI Manual <ref>Smith, D. 2006. Permeable Interlocking Concrete Pavements; Selection, Design, Construction, Maintenance. 3rd Edition. Interlocking Concrete Pavement Institute. Burlington, ON.</ref>
The following calculation is used to size the stone storage bed (reservoir) used as a base course. It is assumed that the footprint of the stone bed will be equal to the footprint of the pavement. The following equations are taken from the ICPI Manual <ref>Smith, D. 2006. Permeable Interlocking Concrete Pavements; Selection, Design, Construction, Maintenance. 3rd Edition. Interlocking Concrete Pavement Institute. Burlington, ON.</ref>
===To calculate the total depth of the stone reservoir (all graded layers)===
===To calculate the total depth of the foundations (d<sub>f, max</sub>)(all aggregate layers)===
The equation for the depth of the stone bed is as follows:
The equation for the depth of the stone bedding is as follows:
<math>d= \frac{[Q_c\times R + P - f'\times t ]}{V_{R}}</math>
<math>d_{f, max}= \frac{[Q_c\times R + P - f'\times t ]}{V_{R}}</math>
{{Plainlist|1=Where:
{{Plainlist|1=Where:
*''Q<sub>c</sub>'' = Depth of runoff from contributing drainage area, not including permeable paving surface (m)
*''Q<sub>c</sub>'' = Depth of runoff from contributing drainage area, not including permeable paving surface (m)
*''R'' = ''A<sub>c</sub>''/''A<sub>p</sub>''; the ratio of contributing drainage area (''A<sub>c</sub>'') to permeable paving area (''A<sub>p</sub>''). Note that the contributing drainage area (''A<sub>c</sub>'') should not contain pervious areas.
*''R'' = ''A<sub>c</sub>''/''A<sub>p</sub>''; the ratio of contributing drainage area (''A<sub>c</sub>'') to permeable paving area (''A<sub>p</sub>''). Note that the contributing drainage area (''A<sub>c</sub>'') should not contain pervious areas.
*''V<sub>R</sub>'' = Void ratio for stone bed (typically 0.4 for 50 mm dia. [[reservoir aggregate|clear stone]])}}
*''V<sub>R</sub>'' = Void ratio for stone bed (typically 0.4 for 50 mm dia. [[reservoir aggregate|clear stone]])}}
On highly permeable soils (e.g., infiltration rate of 45 mm/hr or greater), a maximum stone reservoir depth of 2 metres is recommended to prevent soil compaction and loss of permeability from the mass of overlying stone and stored water.
On highly permeable soils (e.g., infiltration rate of 45 mm/hr or greater), a maximum stone reservoir depth of 2 metres is recommended to prevent soil compaction and loss of permeability from the mass of overlying stone and stored water.
===To calculate the invert of the underdrain from the base of the reservoir===
===To calculate the invert of the underdrain from the base of the reservoir===