US1705066A - Construction of roads - Google Patents

Description

' s. s; SADTLER CONSTRUCTION or noms 1 Filed Aug. 2a,A 1926 March 12, 1929.

/v VEN Toi/ Samue/,ad/ez BMW .ll/mum .H TTOR/VEY WITNESS Patented Mar. l2, 192.9.

. UNITED STATES --flSA'TENT oFFicE. i' 7 SAMUEL s. sADTLEn, or srnmermnn'rownsmr', MoN'reonEav-ooUNT-Y, rENNsYI.-

vaina, AssIGNon mo'amnslrn -vroUNnAmIoN coMrANY'-, A conrom'rrouor DELA..

'In the ordinary1 manner of making black` layer .of broken stone, cement or' other foundation material; by then placing o n the roadbed thus prepared, the said foundation' material and on that .the top o r lsurface course. But I have found thatwhen a road is to be built in and ythrough certain sandf clay or clayey soils, the earth which is removed 'for the reception of the foundation course may be readilygtreated and then utilized as the main or principal ingredient or constituent of the foundation course. 1

It is the object, therefore of my invention to utilize and to incorporate into the material of the road foundation much of the soil excavatedin preparing 'the roadbed and to so work or treat' such soil or earth as to produce therefrom a 'highly satisfactory permanent, somewhat yielding or resilient Water-resisting foundation.

A further object of my inventionis to lessen the cost of road construction through certain 'soils by making it unnecessary to prepare. and transport to the road-ma ing operation, broken rock or other materials commonly used as the mainoonstituent of 4a foundation course and to utilize and substitute therefor the clayey soil which vwas removed in making the roadbed.

A further object of my invention is to provide a road foundation which is resili- .ent or slightly yielding and in which is incorporated means to distribute the load of the trafiicon the surface course over a r'elatively large area of the foundation course. A further object of my invention is to pro 40 vide a road construction ,with one or more intermediate courses or layers of fabricated 'material operative to distribute theload of traic on the surface course over a relatively large area of the foundationcourse.

A further object of my invention is to provide a roadway, the chief ingredient of which is clayey or sand clay soil; to protect A'saidcourse when laid from the action of any water which may ass through the upper i0 course or courses of) the road; and to interpose between the foundation course and yielding top course, a layer or course of fabricated metal operative to spread. the

l coNsTaUc'rIoN or manaI weight of traffic on the Aupper course-overa relatively largear'eaof the foundation course. .'55y

Other objects of my invention will appear 1n the specification and claims below. In the drawing forming'a part of this specification and'in which the same refer ence characters are employed throughout the 6o various views?.A

Fig. 1 is a vdiagrammatiif: .view intrans-4 verse cross-section showing the curbing and the foundation course in place 4and' then in spaced relationship" thereover, the 'various' 65 courses or layers employed in constructing the road embodying .the invention of .this application. V .Fig 2 is a similar cross-sectional view of theroad after .the courses have been placed in order upon the foundation. l

' The abovejdrawin'gs are not strictly to scale. The thickness of the weight distributing courses and size of .the mesh of the fabricated metal coursel are greatly exagy gerated for the sake of making'clearthe construction.

It is desirable that there be on both sides of the road a retaining wall,curb or cement' gutter to prevent any lateral movement of. l l

the foundation due toftraiic thereover or .the action of the elements. In preparing the road, therefore, I excavate in the soil 1 a trench or channel-the width of which'is the full width of the roadbed including .the Width of the curbing, and the bottom 2 of the trench (or top 2 of the roadbed) is brought to the proper grade and crown. .I then-preferably place the cui-bin 3 along both sides of the roadbed 2, This curbing 3 lmay be of any approved type and may be and preferably is of concrete cast inv the. usual wooden moldsor against mold boards spaced from the .outer sides of the excavation and serving to retain the moist or wet concrete in position until the cement or coni crete sets, after which themold or molding boards may be removed, leaving the concrete curbing 3 in place where it was-cast.

Where the roadbed is normally wet or draining is4 required, I may provide French drains 4 in the top surface of the roadbed 2 to be filled with any suitable material 5, such as cinders, broken stone or -even my foundation material referred to below, or

`any other material which will permit of the slow flow of water therethrough to keep the foundation dry.

stakes tov Substantially the f of .stakes l6 rather near the curbing 3l for purposes to be referred to again below.

After theroadbed 2 has thus been formed,

the curbing set and the roadbed staked, I

' may prepare my foundation material by -mixing thesoil, which Was removed in excavating for the roadbed, with cement and hydrated lime thoroughly mixing ithese three constituents together in any suitable'- manner', as in a pug mill, or other mixing apparatus, in the presence of water. The action of the lime is to render any clay in the soil non-plastic'and to act as a binder and filler with the cement used. In making this foundation, I prefer to mixsubstantial-l ly five to ten parts by volume each of cement andhydrated lime with substantially one hundred parts by volume of the soil m the pug mill or other mixer in the presence of Water. Caustic lime ma be used, but it must be hydrated just be ore or during the mixing. A sufficient amount of soil is put into the mixer, the mixer is started, and the lime and 4cement are added and then the water. The amount of water to be added should be sufficient to enable the mixer to be dumped and the contents spread with little effort to the proper-level. The amount ofr Water, therefore, will depend upon the character of the soil, and somewhat upon the -Wetness of the soil itself. Clayeysoil re-V quires more Water" than sandy.

lAfter a thorough mixing of these materials has been accomplished, the contents of the mixer are dumped upon the top of the roadbed 2-and spread to the properlgrade and level, as may be indicated by the tops of the stakes 6. Since there Will e a slight shrinking of the. Wet mix in drying, especially with clayey soil, the foundation course 7 so formed and placed, should cover the tops of the stakes 6 by probably half an inch. y l

It is desirable to have an excess of lime so that it will vreact with carbon dioxide of the set more fully.

tially'dry. When it is hardened sufficiently' tobe firm, it is rolled with a heavy roller to compact it, and `then allowed to dry and v In preparing the'foundation mix I may add to. it the soluable salts of the iron and aluminum groups, such, for instance, as ferrous sulphate or aluminum sulphate.-v

These 'chemicals react with the lime, to release the ferrie hydroxid and, aluminum hydroxid. Their actionis to shorten the time requiredfor the mix to set. .These lsoluble salts may be mixed with the Water. Which is added. in the making of the foundation material or they may be mixed with the lime and added to the soil; with the lime. I

generally use about 10 pounds. more or less of either of these salts per cubic yard of the mix.

After the foundation 7' has thus been ably about one inch mesh and the e ges of.

adjacent strips are Wired or bound together.. This Wire fabric course 9` extends over the full width of the roadbed and preferably lapsA up against the curbing 3. After having been placed -I prefer' tosecure this fabric and the tarred paper beneath it; to they tops of the stakes 6 by fastening means such as nails,'staples or the like, to hold the -WireA fabric l9 from lateral or transverse movement. The chicken wire 9' is preferablyV galvanized and in six foot Widths. The edges should be joined together with a galvanized Wire lacing and the --strips should be stretched when fastening them to the stakes G. The edges of the Wires should be securely fixed to the posts next .adjacent to the concrete curbing 6. It is desirable to. secure ythis Wire mesh fabric to stakes at or near vthe sides of the road and this is the reason why I have above stated that one row of stakes 6 are preferably adjacent the curbing. It is, of course, understood that these stakes or posts 6 may be driven in the roadbed .for the'mere purpose of securing vthe Wire mesh fabric thereto but when stakes or posts are used, to indicate the level toy .which'the foundation is to be brought they 'may be utilized to also form suitable anchorages for the Wire mesh fabric, particularly along thesides of the road near the curbing..

Before or after the wire mesh fabric 9 has been placed a thin layer or course 11 -of liquid 'asphaltic material may be spread or painted over the tarred paper 8. The purpose of this asphaltic materia-l is tol provide a layer or course of waterproofing material for tlie'foundation course 7 and to thoroughly coat the strands of the Wire fabric with asphalt to protect them from, corrosion.

By spreadingthe layer 11 of asphalt over the chicken wire course 9 after ythe latter has b een placed and secured tothe stakes 6, the Wire strands of the wire fabric are perhaps better coated with the asphalt than when the asphaltic layer 11 is spread on the foundation on tarred paper course 8' prior to fastening thewire mesh fabric in place.

The top or surface course 12 is then placed on the course of reticular metal fabric9. This surface or top course l2 may be of any suitable surfacing material but it is preferably a blak surfacing material, such as Aniiesite, and composed of a lower layer 12 of broken stone coated with asphalt and ,of asize that would not pass through a 11/ screen and be retained on one of lys (both with circular openings), and an upper or surface course or layer 12" consisting of smaller pieces of broken stone similarly coated or covered with asphalt composition. This surfacecourse12 so placed is rolled and compressed by a suitable roller and I preferably sprinkle over the surface after rolling a thin layer 13 of sand or dust to more perfectly seal the surface. In some cases, only `a single course such as l2 is used, instead of two `courses as above referred to.

In some localities or under some circumstances, it may be possible-and desirable to `omit the retaining walls or curbing 3 in which event the foundation material is preferably made in two batches, one the regular or standard mix, Such as has been above described, and the other a like mix to which has been added rather more cement, say two or three times the amount. This cement-like mixture should be run or spread on both sides of the roadway for about 9 to 18 inches in width. In other Words, the foundation thus made would consist of two edges orstrips along the side of thc road, located'about where the curbing 3, shown in the drawing, islocated and about 9 to 18 inches wide. Between these strips or bands of stronger mix the main body or mass of the foundation is composed -of the regular 'mix above described'. The two mixtures are prepared and'laid at the same time. g The cement-like mixture at the sides of the road i from the road construction the'course 8 of tarred paper and the mesh fabric 9 above described. The'chief value of the wire mesh is to make the road more rigid while the foundation is becoming more and more firm and compact.

'The thickness of thetarred paper course 8 and the thickness of the wire fabric course 9 and the mesh of the wire fabric 9, as shown in the drawings, are greatly exaggerated asv Y' 9 is in practice less than the diameter of the stones forming the lower part 12 of the .upper 'or surface course 12. The nails or asphalt or oil thus applied. enters into' they interstices of the wire mesh, covers the wire thereof and lies on the top surface lof the f tarred paper course 8y after it has been applied, and the layer 'stones on the bottom part of the surface course 12 in practice, rest of course, upon the wire mesh fabric 9 above described.

lVhen the road isl to be made in very sandy soil or in sand itself, before this foundation mixture is prepared andI laid as a foundation course, I preferably Wet the roadbed2 with water so that the' water contained in 'i the mixture-will not flow from the mixture into the roadbed before a chemical reaction between the materialsl in the foundation has been effected. A

- This mixture so formed is quite plastic, can be readily placed in and around the roadbed and broughtto suitable crown and grade. lith a foundation thus prepared, thev tarred paper course 8 might possibly be omitted but the course 9 composed of the vwire mesh fabric coated with asphalt as 'above described, for distributing the load on the top course 12 over a considerable area of the foundation course 7 is more vital to my invention.

After the wet foundation 7 has thus been placed on the roadbed 42, it should be' allowed 'to stand until it is capable of supporting a vroad roller.

The foundation 7 having thus been placed and compressed by rolling, the course 9 of wire mesh fabric is secured to the tops of the stakes 6, suitably placed ltherein, vand a coating or course 11 of liquid asphalt is applied to the chicken wire fabricandto top surface of the foundation `course 7.

Any suitable surfacing material, such as Amiesite, may be laid down as a top o r surface course 12 and rolled, in the mannerv above indicated. f

The French drains 4 are placed wherever found desirable to have them and may be filled with any suitable material 5 such as cinders or clayey earth that has been heated or baked to a temperature of about 2500, or with a mix of sandy soil and lime.

The surface course 12 which is preferably Amiesite, comprises a broken graded stone, pieces or the particles of which are thoroughly coated with an asphaltic composition and when placed is rolled cold. It yields `slightly under the load of traffic. It doos not spread under such traffic or roll up l in advance'of the wheels of a heavy vehicle.

It "is'merely somewhat' elastic or resilient.

wheels of a vehicle and the roadway over.

which the vehicle is-traveling, that pressure i on that comparatively small area of the course-12 is imparted to the wire mesh fabric course 9 and by it is distributed over a lin 'anyv direction.

. orv 'transverse movement. whole, i s firmly retained between the curb-l ing-3 oni opposite sides ofthe road with the [relatively large area. of the foundation course-7. Such largearea of my improved foundation material over which the load of 'p traiiicis thus distributed isamply sufficient l to support'the load of traiiic without creeping or spreading and without being depressed or' compressed, and without moving The rigid firm .retaining walls or curbing 4 likewisey hold the foundation 7 as lwell as thetop course 12 of the road from lateral result 4that afoundatiomcomposed and laid as above described isfa very permanent one,

capable of withstanding without undue wear,

heavy traiiic thereon, and fully n and completelyprotected from the actionof water thereon. By lapping the edges of the open then compressing. it between the upper course 12 of the roadway and the curbing 3 the lwire fabric 9 is iirmly embedded inthe -bottom of thel upper orv surface course 12 andthe ends of it are substantially'clamped between the said upper course 12 and the immovable curbing y Having thus described my invention, what I claim and desire to protect by Letters Patent of the United States, is.:

1,'Themethod of constructing a roadway in a sand-clay soil, which consists in excavating'and leveling the soil to the grade of the roadbed, mixing the excavated soil with cement, calcium hydroxide and water, and stirrinfr the same together until the mixture isunifjorm throughout and then placing a.

course of the mixture vso made on the roadbed and compacting the same to form a foundation'. course, andallowing same to set jf 2. `'Ihemethodof constri'lcting a roadway in ajsandclay soil, which consists in exca- .vating and leveling the soil to the grade of the roadbed, mixing the excavated soil with y. notmore than 10%,by volume each ofggce-.f

ment and calcium lhydroxide calculated to the soilor sand. used, and stirring'the same together lin the presence ofl water until the mixtureA is uniform throughout and then The. road as a stirring placing a course of the mixture so made on the roadbed and compactm the same to form a foundation course, an allowing same to set and dry.

3. The method of constructinga roadway in a sand-cla soil, which consists in excavatvngand leve ingtheisoil to the grade of the roadbed, mixing the excavated soil4 -with about 5% by volume of cement and about 10% by volume of calcium hydroxide, calculated to the soil or sand used, and stirring `the same 'together in the'presenc'e ofwater until the mixture is uniform throughout and then placing a courseof the mixture so made the soil to the grade of the roadbed, placing p,

.rigid means on opposite sides lof the roadway for preventing the lateral movement of the foundation course, mixing the excavated soil with cement, hydrated lime and Water, and the same together until the mixture .is uni orm throughout, placing a course of the mixture so made on the roadbed allowing the placed material to har-den sufficientl tosupport4 a roller," and then compacting tie same to form a foundation course, pro- `viding said foundation course with stakes, fthe top ends of which are iushf with the mesh fabric up against the curbing 3 and -top surface of said foundation course. placing on the said foundation a courselof fibrous material, placing on 'said fibrous material a -course of open mesh metal fabric, stretching to coat said fibrous course and said metallic` fabric.

5. The method of constructing in a clayey soil, a foundation for a roadway having a surface course which yields slightly under the load of trailic, which consists in excavating and leveling the soil to the grade and crown of the roadbed, mixing the excavated Vsoil with cement, hydrated lime and Water and thoroughly stirring said materials together to produce a mixture uniform throughout the massv thereof, placing a course of the mixture so made on the roadbed and allowing the placed material to partially dry and then compacting the same 'to form a foundation course, placing on said foundation. a course of brous material, comprising sheets of tarred paper with the edges thereof overlapped to shed Water, placing on said paper, strips of open mesh metal fabric with their adjacent edges bound together, ixedly fastening said metal fabric to said foundation course,- and applying a liquid asphaltic material to said metal fabric and to the upper surface of said paper to protect the metal fabric from corrosion and to render said paper impervious to water.

6. The method of constructing in a clayey soil, a foundation for a roadway having a surface course which yields slightly under the load of traffic, which consists in excavating and leveling the soil to the grade of the roadbed, mixing the excavated soil with cement, hydrated lime and ywater in substantially the porportions by weight as follows: 100 parts by volume of said soil, 5 to l0 parts of cement, and 5 to 10 parts of said lime and sufficient water, andV thoroughly stirring said materials together to produce a uniform distribution of said materials throughout the mixture, placing the mixture so made on the roadbed and compacting the same when sufficiently dry to form a foundation course, placing on said foundation a course comprising sheets of tarred paper having adjacent edges overlapped to shed water, placing on said paper course strips of open mesh metal fabric and rigidly securing the same and lsaid sheets of paper to said foundation course and applying a liquid asphaltic material to s aid metal fabric and to the upper surface of said sheets of paper.

7. The method of constructing in a clayey soil, a foundation for a roadway having a surface course which yields slightly under,

the load of traffic, which consists in excavating and leveling the soil to the grade of the roadbed, mixing the excavated soil with cement, hydrated lime, soluble salts of the iron or aluminum groups and water, and thoroughly stirring said materials together to produce a uniform mixture throughout, placing a course of the mixture so made on thc roadbed and allowing it to partially harden and then compacting the same to form a foundation, placing on said foundation a course of tarred paper and on that a course of open mesh metal fabric, and applying a liquid asphaltic material to said metal fabric and to the upper surface of said tarred paper.

8. The method of constructing in a clayey soil, a foundation for ay roadway having a surface course which yields slightly under the load oftraffic, which consists in excavating and leveling the soil to the grade and crown of the roadbed, laying a foundation course thereon consisting of the excavated clayey soil intimately mixed with substantially 5 to l() parts of the weight of the soil of cement and 5to l0 parts of hydrated lime, in the presence of water, laying on the foundation course, sheets of fibrous material having their adjacent edges overlapped to shed water, placing on said sheets strips of reticular metal fabric with their adjacent edges bound together, stretching said strips of metal fabric and ixedly securing the same to said foundation course, and coating said metal fabric and the upper surface of said sheets with a liquid asphaltic material.

9. The method of construction, in a clayey soil, a foundation for a roadway having a surface course which yields slightly under the load of traffic, which consists in excavating and leveling the'soil to the ade of the roadbed, mixing the excavatec?r soil with lime and water and stirring said ingredients together until the mixture is uniform v throughout and of the consistency of freshly lmade cement, placing a course of the mixture so made on the roadway and compacting the same, allowing the said material to set and dry, placing 4on said cement-like course a sheet of reticulated metal fabriccovered with a liquid asphalt composition and securing said sheet to said cement-like course, whereby when saidsurface course of slightly yielding material is laid on said metal fabric course, the load of traffic imposed upon a relatively small area of said yielding surface is distributed by'said metal course over a relatively large area of said cement-like course.

10. In a roadway having a surface course which, -yields Islightly under the load of traffic, a foundation course composedI of clayey soil intimately mixed with hydrated lime and water to form a compact cementlike composition, a sheet, of fibrous material upon the surface of said cement-like course and a vsheet of reticulated metal upon said fibrous fabric sheet, said sheets of fibrous fabric and metal being covered with a liquid asphaltic composition and lying between said foundation course and said surface course, whereby the load of traffic imposed upon a relatively small area of said surface course is distributed by said metal course over a relatively large area of said foundation course.

In witness whereof, I have hereunto set SAMUEL SaS/ADTLER.

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