US1234171A - Pavement. - Google Patents

Description

Patented July 24,1917'.

FIGLIA..

FIC-l1. 2.

PAVEMENT.

Specication of Letters Patent.

- Patented any ai, mit.

' Application filed January 24, 1917.- Serial No.'1`44,284.

To all/whom 'it may concerns Be it known that I, HENRY J. KAISER, `a citizen of the United States, residing at Everett, in the county of Snohomish and State of Washingtonj have invented a new and useful 'Improvement-in Pavements, of which the following is aspccification.

This invention relates to certain new and useful improvements in `pavements for streets and roads.

One of the important objects of the present invention is to so simplify' the construction of pavements as to reduce the cost of repairs to thegninimum.

Those experienced in the construction and Imaintenance of streets and roads know that one of the most important factors connected therewith, which is emphasized more and more each succeeding year is that of cost of maintenance, and 'it has/been demonstrated beyond question that the cost of i"epairs can only be reduced by improving the construction. y

The travel on streets and roads is increas` ing amazingly, both in'volume and weight, and advanced engineering' methodsI are sought and employed in the construction of crete with a thin layer of oil or other suitpart of this specification, is shown the preferred embodiment of my present invention. Figure 1 is a vertical cross section on line :1e-m in Fig. 2.

Fig. Q is a top View of 'a longitudinal fragment.

Fig. 3 is a vertical "cross section of expansion joint with angle irons attached;

Same letters refer to similar parts throughout the several views.

In carrying out inyinventionl first preparc the foundation or what maybe termed the bed, to receive the 'concrete pavement, for with whatever care the pavement may be laid it is very apt to be a failure unless the'foundation is good and dependable.A It is just as important a factor in road building as in any other work of construction, and while it is true that concreteproperly made and laid has great inherentstrength it gives much better service and needs less attention if it be laid upon a firm, unyielding bed having a smooth, level surface.

Having Such a foundation I lay thereon, and thoroughly ram, a concrete base A varying in thickness from two to eightinches, of a rather lean mixture', bringing thetop to a smooth, evenfsurface by means of a float, trowel or the likef y No expansion jointsare placed in this primary layer so that it may be denominated monolithic in character as it is continuous and unbroken.

After this primary layer of concrete has thoroughly set and hardened there is applied to the surface thereof a sheet of oil crude or heavy) or other suital'ilelubricant, B, especial care beingy exercised to secure `a uniformly even distribution thereof over the entire surface. j

Upon this sheet of oil is placed a layer of paper of suitable thickness, C, to cover com pletely the sheet of oil, thereby preventing and separating, during the process of construction, the secondary layer or wearing surface from direct contactwith the oil and primary labor. l

Immediately4 following the positioning` of the paper in the manner mentioned, the sec# ondary layer of concrete as the wearing surface, D, is superposed on the paper to a depth varying from two to eight inches; for this purpose a richer mixture may be used. The surface of this secondary layer or wearing surface is finished smooth and level by means of a float or the like. i

ln superposing the secondary layer or wearing surface as described, eXpansion joints, E, are placed equidistant, and in order to prevent the oints from rising and thereby allow the contiguous sections to` unite at theii` lower edges under the joint, there are attached to the lower edge yof the expansion joint light weight angle-irons, G,

rat from five to twenty feet apart so that the concrete is delivered onto the angle-irons at the base of the joint, thereby holding the joint in place andysecuring a water-tight joint. Y

When contiguous sections of the pavement unite beneath the expansion joint, much of the benefit for which-the expansion joint is made is lost for the pavement hasnot the same freedom of movement on the base upon which vit rests as it otherwise would, andhence the cau-se of cracks forming at expansion joints ata change in tem-l` perature. -f

The secondary layer or wearing surface may be reinforced by embedding therein f meshed iron or other suitable'material.

4 It will be noted that the expansion. joints provided f forin the secondary layer. or

wearing surface are confined to the said layer whichr makes said layer independent of the base on which itfrests so faras its sliding thereon is concerned, which freedom of movement is far .greater than can' vpossibly be provided in any pavement that consists of only one layer of concrete, and consequently the rcracking of pavement made according to this invention isv reduced to the minimum.

. As the expansion joints under this invention extend through' the secondary layer only, there is no opportunity for seepage of water through'said joints to the roadbed and softening same which' is a frequent rcause of much injury to pavements as ordiyseep therethrough to the roadbed for it is prevented first, by the paper, and second,

by the oil, and third, bythe primary layer of concretebeneath the oil.

Owing to the bottom course being of concrete it allows the top coursetozbe lai-d more uniform by preventing the wet top concrete course from `penetrating or leakiing into the l ibase, as 4inthe case of earth or other porous` subgra'de.-

I claim as my invention j 1. A pavement composed' of two inde- --pendent layers of concrete, the primary layer-resting upon a suitable roadbed and a second layer superposedv on the primary layer witlra sheet of oil or other" suitable lubricant therebetween. l u

Q. A pavement composed of two independent layers of concrete, the primary ayer resting upon assuitable roadbed, and

an upper secondary layer as a wearing surface, and a sheet of oil therebetween.

3.. A pavement composed of twolfindeependentl layers of concrete,l the primary layer resting upon a suitable .roadbedu and an upper secondary layer as a Wearing surface,- and a sheet of oil and a layer of paper therebetween.

4. A pavement composed of two independent layers of concrete, the; primary v layer resting. upon a `suitable roadbed,. an upper secondary layer' as a. wearing surface` with reinforcing means embedded therein,

and 'a sheet of oil and a layer ofpap'er therebetween. -i

5.`A pavement composed of two indeendent layers of concrete, the primaryy ayer resting vupon a suitable roadbed,al 1y `Y upper secondary layer as a wearingsurface," -asheet of. oil and ay layer of paper therebe-v tween,` and expansion joints extendingY from the; top ofl 'the wearing surface to. the vpaper j beneath.

6. A.y pavement' lcomprising 'a' suitable roadbed, a .primary layer of concrete com- 'pacted directly on said roadbe'd, a sheet of" oil applied to the surface ofsaid primary layer, a'layer of paper of suitable thickness covering the sheet of'oil,`a'crust of concrete superposed on'the paper and having reinforcing means embedded therein, and eX- pnnsion joints extending yfl-om the ."top of tliefweariugsurface to the' 5 paper beneath.

v7. A pavement composed of two independent .layers of .concriete, the primary layer resting upon .asuitable roadbed," an .upper lsecondary layer as a wearing surface,

a ,sheet-of oil vand a layer of paper t herebe tween, and@ expansion jointsextendmg from the top of the wearing surface to the paper beneath and provided vwith angle-irons at their loweredges. .j

8. A pavement comprising `a suitable sub-l grade,v a primary layer of concrete. supported directly upon said subgrade, v.a sheet of 1 oil applied to the surface of said primary layer, a layer ofrelatively tough paper of suitable thickness covering the sheet of oil,

a crust ofconcrete .superpowd on the paper as a wearing surface and expansion jomts dividing said wearing sunface into sections'A adjacent to. each other, said `expansion ing surface to the paper bene'atli.

HENRY J. KAISER. I

joints `evtendinzgf from the topfof the Wear-

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