Composite railroad tie

Claim 1

A railroad tie of composite construction, said tie comprising in combination, uppermost and bottommost elements of rectangular section constituting the top and bottom surfaces of the tie, said elements comprised of hotpressed comminuted liqnocellulosic material having a density range of 0.75 to 1.2 grams per cc, an innermost component containing the tie neutral axis at laminated hotpressed particleboard consisting of particleboard lamina, each lamina having its broad faces perpendicular to and offset from said elements, each of said particleboard lamina having its fibres substantially in parallel relationship to the lamina broad faces and thereby contributing significant horizontal shear strength to the tie, dimensioned lumber elements extending the length of the tie and located immediately above and below said innermost component, said lumber elements having a grain direction parallel to and offset from the tie neutral axis, said dimensioned lumber elements offset remotely above and below the tie neutral axis and thereby contributing tensile strength to resist ending loads applied to the tie, and adhesive means joining all tie components into a unitary mass.