Three ply bolted temporary road mats and apparatus for manufacturing same

Abstract

An apparatus for making temporary road mats characterized by multiple layers of mutually perpendicular elongated timbers having an array of vertical intersections aligned in lateral rows. The apparatus includes a gang drill that moves relative to a roughly assembled mat for sequentially drilling the lateral rows of intersections.

1 . A bolted three ply temporary road mat comprising; a bottom layer of elongated timbers aligned in parallel rows in a first direction; a middle layer of elongated timbers aligned in parallel rows on said bottom layer extending to a second direction transverse to said first direction; a top layer of elongated timbers aligned in parallel rows on said middle layer and vertically aligned with said timbers of said bottom layer whereby said timbers of said layer overlie at an array of vertically aligned intersecting surfaces; through hole formed through said timbers at said intersecting surfaces; and bolts having threaded shanks extending through said through holes with heads engaging the upper surface of said timbers of said top layer; and nuts threaded on said shanks and compressively engaging the lower surface of said timbers of said bottom layer thereby forming a bolted composite assembly of timbers.