US2349910A - Joint construction - Google Patents

Description

May 30, 1944. c. L.. METHVEN 2,349,910

JOINT CONSTRUCTION Filed June 1e, 1941 l V q A el /l O F/G 5 6 $758 .59 617!! a /l y "W i s, I- 72 0, Q2 4 /la y f Y, "QW a f .fl/0 l A W A I f 9" f ze l Why-v 36 l0" 3 O i 4 /NvE/vv'o F 35 CLYDE ..METHI/EN Gm, @Mmm ATTae/v YJ Patented May 30, 1944 UNITED STATES PATENT OFFICE` JOINT CONSTRUCTION Clyde L. Methven, St. Paul, Minn.

ApplcationJune 19, 1941, Serial No. 398,792

8 Claims. (Cl. 94-18) This invention relates to improvements in the construction of expansion joints for pavements and the like. The present application is a continuation in part of my application, Ser. No. 146,877, filed June 7, 1937, which was a division of my application, Ser. No. 670,317, filed May 10, 1933.

Paving practice of the present day requires expansion and contraction joints which are usually filled by some sort of bituminous material. Such joints are of two general types, the premclcled in which bituminous materials are combined with fibrous or elastic material to fill the joint space, and the poured type in which plastic bituminous material is poured into a molded joint space formed in the pavement.

When pavements are contracted in cold weather, inltration of Water frequently occurs at the joint, most of this water being surface water which nds its way through the joint to the subgrade below the pavement. In freezing tem` peratures this moisture freezes into ice lenses in the subsoil which causes heaving of the pavement slabs at the joints. It is also to be noted that the shrinkage of the paving material and of the bituminous material is in opposite directions so that in cold weather the bond between the pavement and the bituminous material is broken thus forming crevices through which water iinds its wayto the soil below the pavement.

Thus far, the eiort of engineers working in this eld has been directed to making the expansion joint as watertight as possible at the top of the pavement. But the results attained have not been satisfactory because of the formation of crevices in cool weather herein referred to, resulting in inevitable infiltration of surface water through the joint and into the subgrade soil.

In cool weather there is also a crevice along the sides of a pavement adjacent to the earth shoulders. Any joint, whether of bituminous material or the so-called air cushion metal box type, which is not absolutely watertight on the ends may still, through these ends, admit much infiltration of water above the elevation of the `bottom of the slab. This water flows into the lower section of the joint and thus passes through into the subsoil below. 'Hollow metal box types of expansion joints are not made with enduring metal in their lower portions. In a comparatively few years, disintegration of this portion permits the infiltration of Vwater through the ends and thus through the corroded metal into the subsoil below the pavement.

In addition to the heaving caused by water freezing below the pavement in the cold climates, there is the disadvantage that in the warmer climates the moisture seeping through the joint produces an expansion of the subsoils which may result in permanent deformation of the pavement.

It is the primary object of the `present invention to provide an expansion or contraction joint with a seal at subgrade elevation, or intermediate the upper and lower surfaces of the pavement which will positively exclude the passage of the water through the joint into the subgrade.

Another object of the invention is to provide a Water seal for expansion or contraction joints so constructed and arranged that it will expand and contract with movement of the adjacent pavement slabs.

Another object is to provide a water seal for expansion or contraction joints of simple, durable and inexpensive construction and which may be employed in connection with any type of expansion joint or so-called dummy contraction joint.

A still further object of the invention is to provide a novel method of placing awater seal at the bottom of the joint space or at an intermediate position in pavements and the like.

In addition, the invention aims to provide numerous improvementsin details of construction and use of apparatus for forming expansion or contraction joints in` pavements and the like having many advantages from the standpoint of efficiency in use, economy in cost and maintenance, and ease of assembly and installations.

Other objects of the invention and further advantages thereof will be more fully brought out as the description proceeds.

In the accompanying drawing I have shown several practical embodiments of my invention but it is to be understood that this drawing is illustrative merely and I do not coni-lne myself to the details of construction therein shown. It will be readily appreciated by those skilled in the art that my invention may be embodied in other forms without departing from the scope thereof or sacrificing any of its advantages.

In the drawing,

Figure 1 is a fragmentary sectional view through a pavement joint showing one of the water seals of my invention; I

Figure 2 is a fragmentary sectional view through a pavement expansion joint showing a modification of my water seal;

Figures 3 and 4 are fragmentary sectional views, similar to Figures 1 and 2, showing modiiications of the water seal construction;

Figures 5 and 6 are fragmentary sectional views through a pavement showing a so-called dummy contraction joint with a water seal of my invention applied thereto;

Figures 7 and 8 are other modifications of the invention showing dummy contraction joint seals and a method of placing them in the pavement.

At the outset, it will be understood that the invention herein to be described and the modidcations thereof may be applied to any type of pavement such as ordinary read pavement or bridge work, roong and to inclined or vertical sections such as wall structures, dams and the like, requiring water-tight expansion or contraction joints.

Referring now to Ithe drawing, and particularly to Figure 1, `the reference numerals I5 and I6 indicateadjacent separated slabs of pavement made of -concrete or any other suitable material which expands and contracts with temperature changes. The space between the adjacent edges of said slabs is usually filled with suitable bituminous material ll which is either poured into the space while in liquid condition or is occupied during construction as a premolded mixture of bituminous and fibrous substances. As will be seen from the said Figure l, said expansion joint material extends from the top of the pavement to a point substantially near the bottom of the said slabs.

The water seal of my invention comprises a flexible metallic member which extends along the joint .from onelongitudinal edge of the pavement to the other conforming to the cross-section design of the pavement and contour of the subgrade. The said metallic member is provided with laterally extending .portions i3 and i9 which underlie the sla-bs l5 and I6. The outer marginal edges of said portions i8 and I9 are bent upwardly to form flanges 2B and El which are embedded 2in .the slabs l5 and lli. At the center, the said metal member is bent to form a number of loops 2?. which are provided for the purpose -of .permitting expansion and contraction of the metal member in accordance with movements of the adjacent slabs due to temperature changes. Preferably, these loops or bends will not be Ytoo sharp, thereby avoiding the danger that the continued eXing of the metal member over aperiod of years might cause rupture.

The member comprising the water seal may rbe made of any suitable metal but, preferably, the metal should be enduring and non-corrosive in order to increase the life of the joint and to eliminate, so far as possible, maintenance costs. Suitable metals such as copper and the like may be best used for this purpose.

While from practical considerations of installation `and maintenance the water seal of my invention is preferably made of enduring metal, I wish it to be understood that I do not limit my invention to use of such metal. Under certain conditions it will be quite possible to employ a brous material or fabric coated with a suitable flexible substance to make it water proof and suiciently rigid to retain the shape of the bends and loops formed in the seal. Such materials as composition roofing Vand the like may be employed for this .purpose as wellas the enduring metals referred to.

It will now be seen that because of the construction and arrangement of the water seals herein described, it will be impossible for water t0 find its way through the joint into the subsoil. Also, it would be impossible for moisture existing in the subsoil, and the soil itself, to find its way into the joint. This is assured by reason of the fact that the laterally extending portions of the water seal underlie a substantial part of the adjacent pavement slabs and for their entire length. Additional assurance is afforded because of the marginal flanges which are embedded in the pavement slabs.

In order to prevent the entry of subgrade soil into the loops of the water seal, I provide a shield 23 which underlies the water seal and which eX- tends from one longitudinal edge of the pavement to the other. By this arrangement I prevent the possibility of the soil accumulating in the loops or bends of the water seal which would interfere with the free flexing movement of the said water seal.

The foregoing description will make clear a practical embodiment of my invention. It is obllo vious, however, that the water seal of my invention is susceptible of embodiment in a great variety of other forms and I have chosen to illustrate severalsuch modifications herein.

In Figure 2, there is shown a modification in which the water seal is provided with laterally extending portions 25 and 26 which underlie adjacent slabs 21 and 28 of the pavement. In this case, as in the structure shown in Figure 1, the said laterally extending portions are provided with flanges 29 and 30 which are embedded in the adjacent slabs. However, in this form, the water seal is provided with but one loop or bend 3l which is formed centrally of the metal member comprising the water seal and which extends upwardly vinto the space between the adjacent slabs. Under ordinary conditions this single loop of the water seal will be sufficient to provide for freedom of flexure dueto the movement of the adjacent slabs. In this figure, I have shown a portion of a removable core mold which rests on 'the Vportions 25 and 2S of the water seal. This structure is 'more fully described in my copending application Serial No. 146,877. In this case 'also I have provided va shield 33 which prevents movement'of a subsoil into Athe loop of the water seal which is located in the space between the adjacent slabs.

In Figure 3 -I have shown a further modification of my vwater seal. In this case the water Seal compri-ses a met-al member having a centrally formed loop or bend 3D which is locatedin the space between adjacent slabs 3| and 32 of the pavement. This water seal is provided with laterally `extending portions 33 and 34 whichare bent upwardly `and embedded in the adjacent slabs. This type of structure will also form an effective seal 4against the passage of moisture through the joint into the subsoil. Here, also, I-have providedshields 35 and 36 which prevent the subsoil and road paving material from entering into the .loop 30, thus. assuring .free Aflexing movement ofthe seal.

...Figure 4 shows a further modification of the water seal. In thiscase .I have Vprovided a metal member having va centrallyformed loop .or bend 4.1 lprovided with marginal portions 48 and 49 which extend. .upwardly .into the space between the Iadjacent slabs of the pavement and which are provided :at :their upper edges with marginal flangesv 50 and "5l lwhich are embedded in the said pavement slabs. This structure also forms a seal against the` passage of moisture through the joint into the subgrade.

Here, again, I have provided a shield 52 for preventing movement of the subsoil into theloop of the water` seal, and the expansion joint ller material l1 which is gripped between walls 48 and 49 serves to cover the upper surface of the loop and exclude paving material from adhering thereto,`thus insuring flexibility of the seal.

In Figure I `have shown a so-called dummy contraction joint to `which the water seal of my inventionhas been applied. `A dummy joint is merely a crevice formed in the pavement to establish a weakened plane which will predetermine the location of a contraction crack or joint. In the said Figure 5,`reference numeral indicates a section of a pavement in4 which there is a` contraction crack or crevice 56 extending from the upper surface to the `lower surface of the pavement. At and near the upper surface, the crevice is filled with suitable bituminous material 51. l

. In the case of the structure shown in Figure 5, I also employ a water seal extending along ,Y

the joint from one longitudinal edge of the pavement to the other which will prevent the passage of water through the dummy joint into the subsoil. The water seal proper comprises a corrugated metal plate 58 extending under the dummy joint and under the adjacent parts of the Yslab for some appreciable distance on each side of the possible location of a crack. This water seal is corrugated so as to provide for flexing movement occasioned by any movement of the adjacent sections of `the pavement. The water seal is protected by a shield 59 which underlies the same and prevents the subsoil rfrom packing` into the corrugations of the seal which would result in destroying its free flexing movement. To prevent the entry of the paving material into the upper part of 4the corrugations in theseal, I employ an upper shield 60 which rests upon the water seal 58 in the manner shown. The said water` seal 58 is provided with marginal flanges 6| and 62 which are bent upwardly and embedded in the pavement. It will be seen that this structure provides an effective seal against the entry of water into the subsoil through the cracker crevice 56.

In Figure 6 I have shown a modification of my invention as applied to a so-called dummy contraction joint. In this gure, reference numeral indicates a section of pavement which is provided with crevice 66 which forms a so-called dummy joint. At and near the upper surface of the pavement, the said crevice is filled with suitable bituminous material 61. In this figure, I have also provided a water seal comprising a looped member 68 having laterally extending flanges 69 which underlie adjacent sections of the pavement and which are provided with marginal flanges 10 which are bent upwardly and embedded in the pavement. The water seal is protected at the bottom by a suitable shield 1|. To prevent movement of the paving material into contact with the loop of the seal, I have provided a shield 'l2 which surrounds the said loop, as clearly shown in Figure 6. Thus, by this arrangement there will be no interference with the free flexing movement of the water seal on account of the impacting of the paving material or the subsoil. The arrangement shown in this figure is such that the space around the loop 68 predetermines the weakest cross-section o1 75 the pavement, thereby r:assuring the 'location of the eventual contraction crackf or crevice. For example, if the crevice be somewhat misplaced as shown in `dotted lines at 66aandi61alin said Fig-f ure l 6. the Vcontraction crack `or crvice will nevertheless find its place 'to the -seal becausey the seal locates Athe weakest lcross-sectionv ofthe Pavemnts. y i. a `In Figures 'l and 8, there areiillustrated other forms of dummy contraction joint seals which serve not only tov establish a weakened plane for determining the point of crackingupon contractioni but'also serve to seal the joints thus prod'ued..4 1. r f In Figure?, the sections 15 include usual dowel bars |8,\beneath which there is hung-a sealing member, generally designated '80. of thin flexible material such as sheet copper, steel-or flexible waterproof material. The member `includes a central loop 8| which closes uponA itself at 82 and extending-edge flanges 83` and 84 terminating in marginal areas 85 and `86 which serve to lock the marginal edges into water-tight relationship to the sections in which they are situated. The loop portion- 8| is preferably coated with bitumen or other -material to `prevent adherence of the material of sections 'I5-'l5 thereto and hence, as the pavement contracts, the loop will afford flexibility allowing parts` 83 and 84 to pull away from each other thereby opening the loop 8| at the bottom port 82. The edge flanges 85 and 86 are preferably punched to receive hooks or wire fasteners 9| which hold the joint with the upper extremityB'I of the loop 80 firmly againstthe dowel bars 18, from which the entire joint is suspended during placement of the paving material. The joint seal thus is situated on one side the midplane `of. the sections 15. As the sections are poured, they are trowelled to include theV space 93 which is filled with bitumen or other joint sealing compound 94. Upon contraction of the pavement, the contraction cracks 95 and 96 form, being directed by the space 93 and the configuration of the seal.

V In Figure 8, there is an arrangement generally similar to that shown in Figure 7 in which the joint seal is composed of a channel of flexible metal or `non-metal` material |00 having a central downwardly. extending loop |0| and side flanges |02 and |03 terminating in edge flanges |04 and |05 which form water-tight anchorages with the pavement. Channel portion |0| is open at the top and into it there is forced a covering member |06 which may be either a single thickness of material or a channel section made by folding. The member |06 is made of such size that the portions |01 and |08 nest snugly into the open channel |0| and thereby cover thechannel s0 as to exclude paving material therefromY during placement of the unit in the pavement. The

exteriorsurfaces of the member |06 and the ex-v terior of loop |0| are preferably coated with asphalt, grease or other material to` prevent adherence of paving material to these parts. In placing the assembly of Figure 8 in the pavement, it is preferably held by wire ties ||2 and I3 fastened through holes in flanges |04 and |05 and to dowel bars 18 so as to hold portion |09 snugly in contact with the bars. 'I'he assembly is thus held immovable in a position in the sections I5- 15, while the sections are poured. The material of the sections is then placed and trowelled to provide groove ||4 which serves with the contraction joint assembly |00 to initiate the contraction crack ||6 which continues from groove 4 down to portion `H39 of memberrl and thence at H1 below loop tothe lower surface of Athe .pavement. The vilexibleportion IUI serves 'to sealthe crack against passage Y of water therethrough. Groove H4 isaordinarily` filled with Vasphalt or other crack sealing composition. 1

- The dowel bars are left in place in their proper positions to function in the customary manner, these being illustrated-at 7.8 in Figures l, 5, 6, 7and8.J The water seal bands of the present invention are. left in their proper positions with the edges sealed into the adjacent concrete slabsand providing a bend or loop of the seal band, free of any bondor restraining `contact with said adjacenty slabs, capable of, absorbing such pavement movement as the design ofthe joint interval and space requires. e

Many vobvious variations will occur to those skilled in theart and itis intended that such shall be within the scope of the invention herein illustrated, described and claimed.

lclaim as my invention: Y l. An assembly for use inpreventing the passage of water through joints in pavement and the like, which comprises a membrane having a central transverselyv flexible `portion and relatively movable edge flanges extending into the space occupied by the pavement or the like, a protec-` tion member covering said flexible portion on one side, and a second member covering said flexible portion on the other side, said covering members being permanently attached so as to be irremovyable when the assembly is cast into a concrete section.

2.r An assembly for use in preventing the passageof water through joints in horizontal sections such as pavement and the like which comprises a membrane having' a centraltransversely flexible portion and relatively movable edge flanges extending into Ysaid pavement sections to form water-tight anchorages therewith, and a protection member overlying said flexible portion,

protection member being permanently attached and irremovable when the assembly is cast into a concrete section.

3. A joint seal for use in concrete sections such aspavement and the like comprising a long, narrowj` membrane having a plurality of uniform central' convolutions forming a corrugated centrai areay and edge flanges extending into said concrete sections to form 'Watentight anchorages therewitl'lfy 4, An assembly to becast into concrete pavement and thelike to provide'a seal therein at an expansion or contraction joint in said pavement,

rto seal said joint'against the passage of moisture,

comprising aV relatively long, relatively narrow transversely ilexible member having upwardly extendinor sidewalls forming a cross section of concaveshape and lsealing ns extending laterally into the space `occupied by said pavement so as `to form a water-tight anchorage therein, and another member composed yof one sheet `of metal Shaped to lhave a concave cross section, said latter member lbeing positioned between said sidewalls and in resilient contact therewith so as to form a totally inclosed cross-sectional space to prevent paving materials rentering between said walls.

5. An assembly for use in sealing the joints in pavement `and the like, which comprises a relatively long unitary member bent so as to have a central flexibility imparting convolution having a cross-'sectional shape like a loop closed atene point and edge ilanges extending outwardly from the .point of closure of the loop into the space occupied b'yrsa'id pavement to form a watertight anchorage therewith, and a channel having opposed surfaces 'and aloop cross section sufficiently large to embrace the loop of the unitary member and assembled thereon surrounding said loop` shaped convolution, for preventing adherence of the paving material thereto.

6. Anassembly for use in sealing joints in concrete sections which comprises a relatively long member having a central flexibility imparting convolution closed on itself and fins extending therefrom into the space occupied by said concrete sections to form a water-tight anchorage therewith, and a covering over the exterior surface of said central flexibility imparting convolution, for preventing adherence of concrete thereto, said covering 'being so aixed asV to remain attached tothe relatively long member when the assembly is cast into a concrete assembly.

'1. A unitary assembly for sealing joints in horizontal Aor vertical concrete sections comprising a membrane having a central transversely flexible portion and relatively movable edge portions adapted to be placed in concrete on eitherside of the joint and bonded thereto, yand protective shielding means afllxed to and forming a protective covering for the central flexiblev portion for withholding contact of the concrete thereto, said protective shielding means being so affixed as to remain permanently in place when the unitary assembly is cast into a concretersection.

8.4 A unitary assembly for sealing joints in horizontal or vertical concrete sections comprising a membrane having a central transversely exible portion' and relatively movable edge portions adapted to be placed in concrete with one edge portion embedded 'in the concrete at each VsideV of the joint and a protective covering attached to said flexible portion for preventing adherence of concrete thereto, said protective covering being so

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