Abstract A trestle system is made to support fluid material conveyors in the air above the earthen overburden covering permanently frozen earth that is generally referred to as permafrost. The system comprises aligned trestles each embodying two limbs crossing each other at a point spaced well above the overburden surface, the limbs having their lower end portions embedded in the frozen earth and having portions above their crossing point connected by a tie beam upon which the conveyor is carried. The limbs extend outwardly and downwardly from their point of crossing at substantially right angles to each other and to the longitudinal axis of the conveyor. Each limb comprises a horizontal footplate embedded in the frozen earth, a steel lower portion secured to the footplate and extending up through and above the overburden, a mid portion of wood, or equivalent nonconductor of heat, overlapped with and affixed to the lower portion and a steel upper portion overlapped with and affixed to the mid portion, the steel upper portion being affixed to the tie beam and to the other limb of the trestle. Certain of the trestles embody braces to oppose leaning of the trestle lengthwise of the supported conveyor. These braces are each made up of a footplate embedded in the frozen earth and spaced endwise of the conveyor from the crossed limbs, steel lower brace portion affixed to the footplate and extending upwardly and toward the trestle, mid-limb portions of wood or equivalent heat insulating material overlapped with and affixed to the steel lower brace portion and a steel cable connecting the upper end of the mid limb portion to the crossed limbs.
A trestle for support of an above-ground conveyor of fluid material over permafrost ground area, comprising: a pair of upright trestle limbs; the lower end of each trestle limb being adapted to be embedded within a permafrost zone below ground level; a relatively broad fOotplate mounted to the lower end of each limb and adapted also to be embedded within the permafrost zone, each footplate having a horizontal area sufficient to assure permanent support of the trestle limb by the permafrost; each limb embodying a lower limb portion of metal extending from the footplate through the ground surface, a mid-limb portion of heat insulating material affixed to and projecting upward from the lower limb portion, and a top limb portion of metal affixed to the mid-limb portion; the top limb portions of the respective trestle limbs being joined to one another; said top limb portions of the trestle limbs being crossed and fixed to one another; a tie beam connecting the top limb portions of said limbs above the point where they cross; and conveyor support means mounted to the top limb portions of the trestle limbs having a saddle for supporting the conveyor.
Claim 2
Dependent Claim
194 words
A trestle for support of an above-ground conveyor of fluid material over permafrost ground area, comprising: a pair of upright trestle limbs; the lower end of each trestle limb being adapted to be embedded within a permafrost zone below ground level; a relatively broad fOotplate mounted to the lower end of each limb and adapted also to be embedded within the permafrost zone, each footplate having a horizontal area sufficient to assure permanent support of the trestle limb by the permafrost; each limb embodying a lower limb portion of metal extending from the footplate through the ground surface, a mid-limb portion of heat insulating material affixed to and projecting upward from the lower limb portion, and a top limb portion of metal affixed to the mid-limb portion; the top limb portions of the respective trestle limbs being joined to one another; said top limb portions of the trestle limbs being crossed and fixed to one another; a tie beam connecting the top limb portions of said limbs above the point where they cross; and conveyor support means mounted to the top limb portions of the trestle limbs having a saddle for supporting the conveyor.
Claim 3
Dependent Claim
39 words
A trestle as set out in claim 1 further comprising: paired braces extending lengthwise of the conveyor, each brace fixed to the trestle limbs beneath the conveyor support means and extending downwardly and oppositely outward from the trestle limbs.
Claim 4
Dependent Claim
47 words
A trestle as set out in claim 2 further comprising: a relatively broad footplate mounted to the lower end of each brace adapted to be embedded within the permafrost zone, each footplate having a horizontal area sufficient to assure permanent anchoring of the brace by the permafrost.
Claim 5
Dependent Claim
20 words
A trestle as set out in claim 1 wherein the mid-limb portion of each trestle limb is constructed of wood.