Issue 2, 2017

| KNOWLEDGE base InterlockDesign.org 2017 ISSUE 2 esign interloc ® 4 Tech Spec 23 published Feb. 2017. ICPI Releases Technical Bulletin on PICP Maintenance TECH SPEC 23 MAINTENANCE GUIDE FOR PERMEABLE INTERLOCKING CONCRETE PAVEMENTS Available at www.icpi.org , this 12-page bulletin with 33 figures walks the reader through a range of maintenance practices mostly to prevent sediment from collecting on the surface, or remove it should it remain. The bulletin covers practices supporting surface infiltration, such as not using sand in the surface or within the pavement assembly, conducting effective erosion control during and after construction, and maintaining joints filled with aggregate so sediment can be more easily removed from the surface. The text then moves on to surface infiltration inspection and testing, which includes inspection points before and after a rainstorm, as well as surface infiltration testing per ASTM C1781 Standard Test Method for Surface Infiltration Rate of Permeable Unit Pavement Systems . A tool at www.icpi.org for calculating surface infiltration using this ASTM standard is referenced to facilitate better surface infiltration monitoring. The document explains routine and restorative surface cleaning. Routine means periodic preventive cleaning, i.e., keeping the surface water infiltrating. Restorative cleaning is often required when cleaning is neglected. This often results in water ponding on the surface. Sediment must be drawn out of the joints with the help of equipment to increase surface infiltration. Advice then moves into preventive maintenance equip- ment options for maintaining various sized PICP applications. This section provides a range of technologies for cleaning, from a simple broom to sophisticated vacuum truck equip- ment. For clogged PICP with low overall surface infiltration, restorative infiltration maintenance techniques for small and large clogged surfaces are also covered. An inspection list is provided for maintaining surface infiltration as well as a checklist for addressing distresses such as settlement or rutting. Guidance on winter maintenance is included as well as directions on how to reinstate PICP over underground utilities. This information supports cities that use PICP in highly urbanized areas. ICPI releases a new resource, ICPI Tech Spec 23, with a range of cleaning techniques to maintain permeable interlocking concrete pavements.