To prevent rooting of weeds in clearance between a curbstone for partitioning a walk and a roadway, a walk structure and a roadway structure.

Semicircular cross-sectional recesses 13, 14 and 16 having notched or recessed-projecting surfaces are respectively formed on respective opposed surfaces of the curbstone 11 and the roadway structure 12 and respective opposed surfaces of the curbstone 11 and the walk structure 15, resilient rubber packing 17 having a hollow circular cross section is installed in these recesses, and the packing 17 is respectively elastically contacted with the curbstone 11 and the structures 12 and 15 after execution work.