US2166220A - Concrete road joint - Google Patents

Description

July 18,1939. c. QLDER 2,166,220

CQNGRETE ROAD JOINT Filed Nov. 16, 19.36 3 Sheets-Sheet l je we @7502/2- yJuly 18, 1939. C, QLDER 2,166,220

CONCRETE ROAD JOINT Filed Nov. 16, 1936 3 Sheets-Sheet 2 3 Sheets-Sheet 3 July 18, 1939. c. OLDER CONCRETE ROAD JOINT Filed Nov. le, 19:56

Patented July 18, 1939 UNITED STATES PATENT OFFICE 8 Claims.

The present invention relates to` concrete road joints, and many of the features of the invention may be embodied in both the type of joints called expansion joints and contraction joints.

The present application is a continuation in part of my prior application, Serial No. 80,281, filed May 18, 1936 for Concrete expansion and contraction joint.

One of the objects of the present invention is the provision of an improved concrete road joint construction, including improved means for assuring the alignment of the adjacent sections of concrete, such means permitting the relative sliding movement between these sections.

In any joint in which steel is used for dowel purposes, either in the form of a continuous steel plate or separate dowel bars or rods, the stiffness of the steel member is usually much greater than that of the concrete. Both are elastic, but the relative stiffness of steel to concrete is about fifteen to one; that is, within the elastic limits of the materials, concrete yields about fteen times as much as steel under the same unit pressure. Therefore, in a doweled joint, the deflection is much more dependent upon the yield of the concrete than upon that of the steel. If the deflection is to be held to a minimum, the unit pressure `on the concrete must be reduced to the smallest feasible amount.

vThe stiffness of the dowel plates or bars depends upon their bending resistance, but the dowel may be made as stili as desired, simply by making its vertical dimension in proportion to the bending resistance desired. However, the thickness of the concrete roadway is generally predetermined by other considerations than that of the resistance of the joint, and is usually set forth in the specifications relating to the construction.

One of the objects of the invention is the provision of an improved concrete roadway joint in which the deection from the normal or no load plane or position of the roadway to the position under load is reduced to a minimum.

Another object of the invention is the provision.

of an improved concrete road joint, in which vertical play is eliminated, and in which the doweling structure is as stiff as possible with respect to the vertical deflection of the concrete sections at the joint.

Another object of the invention is the provi- Y the concrete over such large areas as to not only eliminate'pressures in excess of the elastic limit of the concrete, but to reduce them to such an extent that the elastic yield will be a minimum.

Another object of the invention is the provision of an improved doweling structure for concrete road joints in which the tendency of the dowel member to split or spread the parts of the concrete section in which the dowel member slides is resisted by an improved structure which practically eliminates any possibility of deflection due to this action.

Another object of the invention is the provision of an improved concrete road joint unit, the parts of which may be shipped knocked down and which may be made of stock parts that can be assembled on the job.

Another object of the invention. is the provision of an improved concrete roadstructure, the parts of which may be constructed of sheet metal so that the parts of the joint may be constructed by stamping operations, thereby reducing the cost of the finished joint.

Another object of the invention is the provision of an improved concrete expansion or contraction joint, the parts of which are adapted to nest with each other so that they may be more conveniently shipped.

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings, in which similar characters of reference -indicate similar parts throughout the several views.

Referring to the threesheets of drawings accompanying the specification,

Fig. 1 is a vertical sectional view through a concrete expansion joint constructed according to the present invention, the section being taken on a vertical plane at right angles to the direction of the joint;

Fig. 2 is a similar view of a modification:

Fig. 3 is a fragmentary elevational view of' the doweling unit of Fig. 2, separate and apart from the rest of the joint and concrete;

Fig. 4 is a view similar to Fig. 1 of another modification Fig. 5 is a fragmentary view of another modiflcation;

Fig. 6 is a fragmentary view of another modified form of doweling structure;

Fig. 7 is a similar view of another modified form of doweling structure;

Fig. 8 is a similar fragmentary view of another modified form of doweling structure constructed of cast metal;

Fig. 9 is an elevational view of the doweling unit of Fig. 8,1ooklng from the right end of the figure, with the concrete omitted.

Referring to Fig. l. I indicates in its entirety the concrete roadway joint unit, which is shown in connection with the adjacent edges of two concrete sections Il and I2. The improved doweling structure may comprise a stock metal member I3 of substantially T shape having the top of the T located as the vertical flange I4 and the stem of the.T as the dowel plate or horizontal flange I5. The vertical flange I4 is preferably provided with a multiplicity of anchoring lugs I3, I1, which are formed by being punched out of the body of the flange |4 at the top and at the bottom, and bent in opposite directions so that the lugs I8, I1 are staggered with respect to each other and extend at right angles to the flange I4. 'Ihese lugs are preferably tapered ln width so that they are widest at their outermost edges and are thereby anchored in the concrete sections and I2.

The concrete section may be provided with the usual reinforcement, but certain portions of the reinforcing are preferably arranged in connection with the dowel structure as shown in Fig. 1. 'Ihe horizontal rods Il, I9 may be located above the lugs I8 and below the lugs I1, and these rods may be secured to vertical rods 2l, sumcient in number and equally spaced, as shown in Fig. 3, to connect the doweling structure with the reinforcing.

In some embodiments of the invention the anchoring lugs I6 and |1 may be welded to the rods I3, |3 or 2li, the rods 2I| being placed adjacent lugs I8 or I1.

The dowel plate flange I comprises a metal member of uniform thickness which is slidably mounted in the concrete section |2. 'I'his may be accomplished by means of a sheet metal shield 2|, which has two parallel legs 22, 23, joined by a U shaped bend 24. The width of the parallel portions 22,23 of the shield 2| is greater than the portion of the plate I5 which is located between these flanges, leaving an alr space 25 just inside the U shaped bend 24 to permit initial expansion of the concrete. 'I'he flanges 22 and 23 tightly engage the dowel plate I5 by virtue of their own resiliency and by virtue of the fact that they are bent to such shape that they spring towards the plate I5, when the plate I5 is removed from between the flanges 22 and 23. 'I'he shield 2| is provided with the upwardly and downwardly extending flanges 26, 21 respectively, which may be of sufficient length in a contraction joint to serve as a division plate for assuring the formation of a crack at the joint unit Ill.

'Ihey may also be used in a contraction joint for clamping between the vertical flange ,I4 and the flanges 28, 21 suitable sheet metal division plates. In the expansion joint structure as shown in Fig. 1, they have the additional function of providing a support for holding the core units 2l, 23. The flanges 24, 21 are also preferably provided with the inwardly turned edges 30, 3| which engage in the concrete of the sections and I2 and provide additional anchorage for the shield unit 2|.

One of the most important functions of the flanges 38, 3| is the distribution of the load which is placed upon the flanges 22 and 23, over a greater area of concrete. The loads which are placed upon the concrete sections and l2 at the joint tend among other things to cause a split of the concrete section I2 between the flanges 22, 23.y 'I'his deflection is resisted by the concrete as well as the shield 2l, and the flanges 22, 23 distribute the forces exerted upon the concrete at the shield over a greater area. These forces are transmitted to the flanges 30 and 3l by the vertical flanges 2G and 2l, and thus the force is transmitted to parts of the concrete not immediately adjacent the flanges 22 and 23, which also assist in resisting forces tending to cause deflection.

The concrete section I2 is also preferably provided with the usual reinforcing, a portion of which is located as shown in Fig. 1, with vertically extending rods 32 located at regularly spaced points and welded to the horizontal rods 33, 34.

The vertical rods 32 are as close as possible to the joint contacting the U-shaped bend 24, to which they may be spot welded, if desired When the doweiing structure is embodied in an expansion joint, it is provided with the core members 28 and 29. These core members may be identical in construction and may consist of relatively thin sheet metal, such as steel, which is adapted to bend when the concrete expands into the spaces 35, 36, after the concrete has hardened, but the core members 28, 29 are of material sufficiently stiff to support the expansible members 31, 38, and to act as end forms for sections of concrete, keeping the concrete out of the spaces 35 and 36.

Each core unit may comprise a pair of vertical flanges 89, 40, which are substantially parallel and which are joined by the bottom flange 4| (referring to core 28). The bottom flange 4| is bowed inward with respect to the core unit 28 so as to facilitate its crushing or folding, after its function of forming the joint has been performed, and when t-he expansion takes place.

The parallel walls 39, 4I! of the core unit 28 may be provided with laterally extending flanges 42, 43 located below the expansible member 31 so as to provide a wider space 44 at that point to assure the fact that the expansible member 31 will never be pinched between the adjacent sections Il, I2 of the concrete.

Laterally extending flanges 42, 43 support the upwardly extending parallel flanges 45, 46, which may terminate short of the upper surface of the concrete sections |I and I2 and are adapted to support the flexible seal 31.

The present joint may be used with various types of flexible sealing members, and the flexible sealing member 31 is merely exemplary of one of the preferred types. It comprises a flexible metal member made of non-corrodible material, such as sheet copper, having a central flexible portion 41, which may comprise the lower flat flange 48 and two upwardly extending flanges 49, 50. The upwardly extending flanges 49, 5|! each terminate in a partially cylindrical bead 5|, 52, the other edges of which are attached to the downwardly extending flanges 53, 54 respectively.

Each downwardly extending flange may carry a laterally projecting flange 55, which is provided with an upwardly turned edge 56, serving as an anchoring formation,

The member 51 may comprise a preformed filler of initially plastic composition, which fllls the groove in the upper part of the flexible seal 31, and which may also serve in leveling off the concrete.

'I'he flanges 49 and 59 slidably engage the flanges 45, and the anges .58, I4 slidably engage the flange 48 so that the seal is suitably supported on the core member 28. The core member 28 fits between the flanges I4 and 28, resting on theA dowel plate I5. -The structure of the lower core 29 and flexible sealing member 58 at the bottom may be similar to that previously described.

The beads 62 in each of these sealing members may be filled with a compresslble or crushable cord 59, which serves to hold the sealing member on the flanges of the core in predetermined position with the bend of the bead spaced from the upper edge of the flanges 45, 48.

The operation of this crushable flller is as follows: When the joint is installed, the parts are held in the position of Fig. 1, the upper flexible seal resting on the flanges 46. 56, the edges of which engage the crushable filler 59. At a later date, when the concrete is hard and the concrete contracts, the widening o'f the space 35 and extension of the flexible seal 31 causes the beads 5|, 52 to be pulled downward. The use of the 'crushable filler 69 provides such a space above the edges of the core plates 45, 46 that these edges will not cut the beads 5|, 52 from the inside.

Referring to Fig. 2, this is a modification in which all of the parts described may be identical except that the shield member` 2| is provided with a different form of member for transmitting force and distributing it with respect to the concrete section I2. In this case the horizontally extending edge 30 has been omitted, but the vertical flange 26 of the shield 2| has also been provided with laterally projecting anchoring lugs 60, similar in form to the lugs I6, I1 on the dowel member I3. These lugs perform the same function as the flanges 30, as force exerted on the flanges 22, 23 is transmitted by the flanges 26 and 21 to the anchoring Alugs 68, which are anchored in the concrete. These anchoring lugs are arranged with respect to the reinforcing bars or rods I8, I9, 2|), as previously described.

Referring to Fig. 3, this is a fragmentary view of the doweling structure as seen from the right of Fig. 2, with the other parts of the joint unit omitted. It will be seen that the shield 2| is provided with regularly spaced and preferably staggered anchoring lugs 60 located midway between the reinforcing rods 20. Anchoring lugs 68 engage inside the rods I8 and I9, which are Welded to the rods 2li', and thus the end of the concrete section I2 is further reinforced against splitting by the interengagement of the anchoring lugs 63 with the reinforcing members.

Referring to Fig. 4, this is another modification, showing one form of expansion joint winch may be constructed according to the present invention. The dowel plate 6I comprises a flat steel plate of suitable thickness, which may be slidably mounted at one or both sides in a suitable shield assembly 62 or 63. The shield member 62 is substantially identical in construction to shield 2 I, previously described, and it works in the same way, except that in this case the shield member 62 may be made of very thin metal, not sufllciently capable, by its own action, of clamping the dowel plate 6I as tightly as desired.

lThis shield member 62 is, however, engaged by a clamping member 64, which has the substantially U-shaped upper portion provided with flanges 65, 66 that clamp the flanges of the shield 62 against the plate 6|,

The clamping member 64 may have a standard 61 which is provided with a foot 68 to provide it 69 into the sub-grade and engages the clamping member 64 adjacent the upper end of the stake.

The joint may be provided with the core members previously described, or with any suitable filler strips 1|, 12, such a's a crushable material, one example being Celotex. Any suitable flexible copper seal 13 may be used at the top and/or the bottom. For example, the flexible seal '13 comprises a U-shaped flexible portion 14, the downwardly extending flanges of which terminate in anchoring flanges 15, preferably having anchoring formations 16.

The groove above the flexible seal 13 is filled with an initially plastic composition 11. The vertical flanges of the shield members 62* ar ld 63 engage the ller members 1I, 12 and holi the unit in assembled relation.

A shield or socket for a dowel plate that is in one piece, as shown at the left side of Fig. 4, presents difficulties in manufacture as regards the tight flat t of the dowel plate and socket. It is ldesirable for economy to use commercially rolled plates for the socket or shield and for the dowel plate.

Such commercially rolled plates of the same nominal thickness vary somewhat in actual thickness because of the tolerance in thickness required by the rolling mills. Hence the slot of a single piece shield must be made wide enough in the vertical direction to accommodate the thickest dowel plate 6| permitted by the mill tolerance. The thickness of the plates would vary within this tolerance, and the thinnest dowel plate 6I of the same nominal thickness would then have a vertical play in the socket 62 or63.

This small vertical play may not in all cases be seriously detrimental, and whenever it is desired to use single piece sockets, such as the shield 62, either the socket slot, the dowel plate 6I, or both, fnay be machined, if deemed necessary. This, however, involves considerable expense, and the structure shown at the right of Fig. 4 is adapted to accomplish a sliding fit more economically, regardless of the mill tolerance in plate thickness.

In this embodiment of the invention the shield 63 is made in three sections 18, 19, 80. Each of the sections 18 and 80 may be similar in shape, being provided with horizontal flange 8|, vertical flange 82, and horizontal flange 83. The section 19 may consist of a substantially U-shaped cap or cover of relatively thin metal, which fits over the horizontal plates of sections 18 and 80 and provides the usual space 25 for lateral movement of the dowel plate 6I.

A plurality of spring clamps 84, located at points along the sections 18-88, where clamping is needed, or where they may do the most good, clamp the horizontal flanges 8| into engagement with the dowel plates 6I and effect a tight, flat contact between these members. For this purpose the clamping members 84 may be of substantially U shape, with inwardly curved engaging portions 85 having aligned contact with the flanges 8|.

In this embodiment the sections are again preferably suitably reinforced as described with respect to Figs l and 2.

Referring to Fig. 5, this is a modification which again may be utilized in either expansion or contraction `ioints, but is shown in connection with an expansion joint of the type of Fig. 4. The

dowel plate 88 may be similar in form to those previously described, except that it is provided with a plurality of spaced apertures 81 on oneA side for rivets 88, and slots 88 on the other side for lslidiibly receiving the bolts 88. The dowel plate 88 is secured on one side of the Joint to a pair of sections 18 and 88, similar to those described in Fig. 4, the horizontal flanges 8| being secured to the dowel plate by the through rivets Referring again to Figs. 8 and 9, in another embodiment of the invention, which requires only one type of unit, both of the sides of the doweling structure may be provided with a unit identical to the socket unit |82, and a rod |88 may be provided which is shorter than the composite length of the bore 28 in both units. it would be necessary to manufacture only one type of unit |82 and provide it with a sliding rod, and both sides of the joint would look like the right half of Fig. 8.

The plate 88 and assembled parts are supported in suitable position by the clamping member 88, similar to that described in respect to Fig. 4, except that the short horizontal flange 83 of the section 88 is slotted to receive the standard 81 of the clamping member.

The right hand supporting unit in Fig. 5 comprises a pair of sections 8|, 82, similar in form to the sections 18, 88, described in Fig. 4, except that they are provided with wider horizontal flanges 88, which may have the inwardly curved edges 88 for receiving the thin sheet metal cap 88, similar to the cap 18, previously described. The horizontal flanges 88 of sections 8|, 82 of the shield member may be secured in tight engagement with the dowel plate 86 by the screw bolts 88, which pass through apertures in the flanges 88 and through a slot or oval aperture 89 in the dowel plate 88.

The initial position of the bolt 88 with respect to the ends of the slot 88 may be that the bolt is centrally located in the slot so that motion is permitted in either direction. Suitable lubrication may be used between the flanges 98 and the dowel plate 88, such as mica lubricant. The operation in this embodiment is the same as those previously described, except that the tendency toward the spreading of the slot in the shield or socket for the dowel plate is resisted by the bolt 88, which is suitably located to most effectively resist such deflection.

The apertures 88, which have been described as slots, may be more economically made as round holes, since then they may be drilled. As shown in Fig. 5 in section, the aperture may be either a slot or a circular bore.

Although the bolt 88 tightly clamps the flanges 88 to the dowel plate 88, sliding motion is permitted without damage to any of these members, the right hand shield being anchored in its concrete section by means of the projecting bolt portions, and the left hand shield being anchored by means of the projecting rivet portions.

In this embodiment of the invention, the cap 88 need not be made of metal, but may consist of a strip of adhesive tape, such as zinc oxide tape or gummed waterproof paper, thereby further reducing the cost in this respect.

Referring to Fig. 6, this is another modification, the right hand portion of which is similar to that of Fig. 5, except that a rivet 88 may be used instead of the bolt 88. In this case the dowel plate 81 is similar in construction to the Then dowel member I8 of Fig. l, except that the plate is provided with slots 88. The slots 88 are located to receive each of the rivets 88 and a cylindrical spacing member or washer 88. The washer 88 permits the flanges 88 to be riveted together on each side of the washer without engagingth dowel plate 81 too tightly.

The slots 88 and rivets 88 are located at regularly spaced points along the doweling unit, and substantially all play is eliminated from the doweling unit by the structure shown. The other details of this joint may be as described with respect to the prior embodiments, and the same numerals have been applied to indicate corresponding parts.

Referring to Fig. 7, this is another embodiment of the invention in which the left hand side of the joint may be as shown in Figs. 4, 5, or 6, but that selected to illustrate the invention is similar to Fig. 5. The dowel plate is again provided with the elongated slots 88 in one edge of the plate, at' regularly spaced intervals, and shield sections 8|, 82, similar to those described in Fig. 5, are employed in connection wtih a strip of adhesive tape 95 for closing -the crack between them.

In this embodiment the horizontal load transmitting flanges 83 have been made wide enough to permit the application of a bolt |88, which passesI through the dowel plate- |8| through the flanges 98 and through the flanges 82. The slot 88 is merely wide enough to permit sliding movement of the bolt |88, and the bolt |88 clamps the sectional parts 8|, 82 of the right hand shield member slidably on the dowel plate |8I, and substantially eliminates all play.

The bolt is also in position to effectively resist any spreading of the flanges 83, due to the action of the dowel plate, and in this embodiment the forces caused by deflection are not only distributed throughout the end of the concrete section, but the tendency toward deflection is resisted by the bolt |88.

Referring to Figs. 8 and 9, this is a doweling structure which may be constructed of cast metal. The right hand part of the unit comprises a circular dowel socket member |82, which is provided with a cylindrical bore |83 of greater length than the dowel |88, thereby providing the usual expansion space 25.

The dowel member |85 may consist of a substantially cylindrical body provided with the cylindrical dowel rod |88 projecting therefrom. Each of these members, that is, the dowel socket member |82 and the dowel member |85, may be provided with a face disc |88 and an outer circular bearing flange |81. The face disc performs the function of the flange 28 of Fig. l, transmitting part of the stress to the flange |81, which is suitably anchored in the concrete and adapted to transmit forces exerted on it to the adjacent part of the concrete section.

The cylindrical bodies of the socket member |82 and dowel member |85 are preferably provided with radially extending bearing flanges |88 (Fig. 9), and a threaded member I 88 may be located in one wall of the socket member |82 to engage the dowel rod |88. Threaded member |89 secures the socket member |82 on the dowel rod |88, but ds not prevent movement due to expansion after the concrete has hardened.

In other embodiments of the invention the thumb screw |88 may be eliminated and the parts held in position by frictional engagement of the bore |88 with the dowel rod |88. In this case the circular flange |01 and wing flanges |08 permit the socket to be rotated to any position without aiexting its bearing on the concrete, and a tight fit may be secured by machining both the dowel and the socket.

It will thus be observed that I-have invented an improved doweling structure for concrete road -joints which may bc utilized in either expansion joints or contraction joints. As distinguished from the devices of the prior art in which there is a tendency for the concrete below or above the dowel plate to split oi before the dowel plate is stressed to full capacity, the present invention is adapted to eliminate the possibility of this destruction of the concrete and to distribute the load throughout the concrete.

The doweling arrangements described herein are oi maximum stiffness, reducing deection to a minimum and practically eliminating any lost motion or play.

The structure of the present devices is such that the forces exerted on the dowel plate tending to spread the dowel plate socket are more effectively resisted, and such spreading is prevented. The present devices may be constructed at a low cost on account of the sheet metal construction, and they may be shipped in knocked down condition and assembled on the job.

inthe preferred embodiment of the invention machining of the parts is practically eliminated, thereby further reducing the cost, and the play resulting from the difference in thickness of dowel plates permitted by mill tolerance is also eliminated.

While I have illustratedv a preferred embodiment of my invention, manymodiications may be made without departing from the spirit of the invention, and I do not wish to be limited to the precise details of construction set forth, but desired to avail myself of all changes within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Pat ent of the United States, is:

1. Ina doweling structure for concrete road joints, the combination of a metal dowel plate With a pair of adjacent concrete sections, said metal dowel plate having one edge carried by the first concrete sectionand having the opposite edge slidably mounted in the other concrete section, the dowel plate in said other concrete section being engaged on both sides thereof by separate sheet metal members, a cap strip cooperating with said separate sheet metal members for forming a slot in said other section of concrete, and clamping means engaging said separate mem bers at a plurality of spaced points for holding said separate members in tight engagement with said dowel plate during the construction of the joint, said clamping members comprising a plurality of substantially U-shaped metal'clamps engaging on the opposite faces of said separate members.

2. In a doweling structure for concrete road joints, the combination of a dowel plate of substantially uniform thickness, said dowel plate having one edge provided with anchoring means adapted to be anchored in a concrete section of the roadway, and the other edge being adapted to be slidably mounted in the adjacent section of the roadway,'a shield for said other edge, comprising a pair of sheet metal members provided with flanges of greater width than the amount of said dowel plate initially projecting into said other section, each of said anges being provided with an inwardly turned edge whereby the edges of said flanges approach each other, and means for closing the crack between said edges, comprising a cap strip, said dowel plate having a slot, and a securing member passing through apertures in said shield and binding the parts of said shield into tight engagement with said dowel plate to resist the splitting tendency of the dowel plate on the concrete.

3. In a doweling structure for concrete road joints, the combination of a dowel plate ci solola stantially uniform thickness, said dovrei plate `having one edge provided with anchoring means adapted to be anchored in a concrete section oi the roadway, the other edge being adapted to be slidably mounted in the adjacent section oi the roadway, a shield for said other edge, comprising a pair of sheet metal members provided with flanges of greater'width than the amount of said dowel plate initially projecting into said other section, each of said flanges being provided with an inwardly turned edge whereby the edges oi' said Iianges approach each other, means for closing the crack between said edges, comprising a cap strip, said dowel plate having a slot, and a securing member passing through apertures in said shield and binding the parts of said shield into tight engagement with said dowel plate to resist the splitting tendency of the dowel plate on the concrete, said securing member cornprising a rivet provided with spacing means in said slot, said spacing means predetermining .the spacing of the parts of said shield.

4. A dowel plate for concrete road joints comprising a member of substantially T-shaped cross section, the top of the T being arranged in vertical position transversely to the direction of the roadway, and the stem of the T serving as a ried by the'first of said sections, said loadtransl mission member extending across the crack between said sections and slidably engaging the second of said sections, and a metal shield member having a plane surface adapted and located for sliding contact with the plane surface on said load transmission member, said shield member being backed up by concrete of said second section, and means for securing the plane surfaces of said members in tight contact with each other during the setting of the concrete, whereby a tight sliding engagement between said plane surfaces and immediate load transmission from one section to the other without substantial play is assured, said means comprising a metal member extending through said load transmission member and said shield member, to bind said members together, said load transmission memextending across one edge oi' said dowel plate, said parallel anges extending to a point between the sections of concrete, each parallel ilange supporting a vertically extending flange, one of said vertically extending iianges extending upwardly and the other extending downwardly, with a filler supported by said joint against said vertically extending ilanges, said illler being adapted to be compressed when the concrete expands, and means extending through said dowel plate and through said parallel anges 1`or drawing said parallel flanges into close contact with said dowel plate, said dowel plate member being provided with a slot for receiving said means extending through said dowel plate, and said slot extending in the direction of its expansion and contraction of the joint whereby sliding movement of the shield and dowel plate member is permitted, the said latter means moving with said shield.

7. In a concrete road joint, the combination of a pair of concrete sections with a dowel plate, said dowel plate having one edge anchored in one concrete edge, and having the other edge slidably mounted in a slot in the adjacent concrete section, said slot being provided with a metal lining above and below said dowel plate, and a metal member extending through said metal lining and said dowel plate, said dowel plate having a slot therein for said metal member, and said latter slot extending in the direction oi movement of the parts of said joint, said metal member binding said metal lining to said dowel plate, to secure a closev slidi'g fit and immediate load transmission and permitting the sliding movement of the parts of said joint as the concrete shrinks or expands.

8. In a concrete road joint, the combination of a pair oi? concrete sections with a dowel plate, said dowel plate having one edge anchored in one concrete edge, and having the other edge slidably mounted in a slot in the adjacent concrete section, said slot being provided with a metal lining above and below said dowel plate, and' a metal member extending through said metal lining and said dowel plate, said dowel plate having a slot therein for said metal member, and said latter slot extending in the direction of movement of the parts of said joint, said metal member binding said metal lining to said dowel plate. to secure a close sliding fit and immediate load transmission and permitting the sliding movement of the parts of said joint as the concrete shrinks or expands, said metal member being provided with a spacer in the slot of said dowel plate, and said spacer preventing the excessive binding of said shield against said dowel plate at said metal member.

^ CLIFFORD OLDER.

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