Introducing preformed inserts into or filling grooves or like channels in laid

Official title: {Introducing preformed inserts into or filling grooves or like channels in laid paving, with or without concurrent making or working of groove or channel, e.g. filling groove with semi-plastic material (E01C23/028 takes precedence)}

E01C23/026 (Introducing preformed inserts into or filling grooves or like channels in laid) appears on 39 US grants and 31 published applications in this corpus.