US2371290A - Method fob installing joints in - Google Patents

Description

March 13, 1945. J. N; HELTZEL METHOD FO INSTALLING JOINTS IN PLASTIC ROADS Filed Jan. 26, 1945 I5 Sheets-Shea?l l noentor Cttornegs March 13,1945. J NHELTZE@ 2,371,290

METHOD FOR INSTALLING JOINTS IN PLASTIC ROADS Filed Jan. 26, 1943 3 Sheets-Sheet 2 attorneys March 13, 1945. J. N. HELTZEL METHOD FOR INSTALLING JOINTS 1N PLASTIC ROADS Filed Jan. 26, 1945 5 Sheets-Sheet 5 mvcntor Gttorncgs )Patented Mar. 13, 1945 UNITED sTATEs PATENT ori-ICE ME'rHoD FOR INSTALLING JOINTS IN PLASTIC ROADS n 'John N. Heltzel, Warren, Ohio Application January 26, 1943, Serial Not 473,640

8 Claims.

The present invention relates to Methods for installing joints in plastic roads, and is a continuation-in-part of my co-pending application Serial No. 363,056, nled October 26, 1940, and entitled Combination road building machine and concrete spreader.

lThe invention has for its general aim and purpose the installing of expansion and contraction joints in concrete or other roadways while undergoing construction in plastic condition.

An object of the rinvention is to provide, either alone or in conjunction with a nishing machine and a supplemental subgrader, a device for car, rying out the method of preparing the concrete to be routed out where transverse contraction or expansion joints are to be placed, in which the purpose of the device i's to separate the plastic concrete from the earth and to avoid the casual or accidental mingling of any earth with the concrete in the process of routing or removing of -.the concrete preparatory to the placing of the .'oint.v

Figure 2 is a transverse vertical section taken on the line 2-2 of Figure 1.

Figure 3 is a similar view taken on the line 3-3 of Figure 1.

Figure-4 is a fragmentary perspective View of an expansion joint employed.

Figure 5 is a similar View of a form of contraction joint employed.

Figure 6 is a perspective view showing a modined form of the invention.

Figure '1 is a side elevation of a machine for' v installing joints, shown above a roadway partly The invention "also has for a further object the use of certain improved steps and processes of a method whereby the subgrade is prepared, joint excavations made in the concrete and the finish;

ing of the concrete accomplished by such steps' as transverse and longitudinal spreading of the concrete, screeding, tamping, follow-'up' screeding and other nnishingoperations.

3, the subgrade is preferably prepared by damp- The' invention has for a stmA further object an improved method by which a plate, or equivalent device, is originally laidv on the subgrade, the plastic lconcrete poured thereover and finished to a`. degree; whereupon the concrete, while yet plastic, is shoveled or routed out 'in a transverse zone above, and dened by, the plate, and as soon as it is reached, the plate itself is lifted out and theexpansion or contraction joint installed in the clean clear cut well defined space provided. With the foregoing and otherobjects in view,

' the invention `Will be more fully ldescribed hereinafter, and will be more particularly pointed out in the claims appended hereto. f l

1n the drawings. wherein like symbols refer to 4like or corresponding parts throughout the several views, Figure 1 is a perspective view, with parts broken' away and parts show in section, illustrating a form of-shoveling constructed andpracticed according to the present invention.

ening, by cutting, by dragging, by compacting, and above all by vibrating during all or any one of these various steps; the subgrade being thus treated and prepared between the customary side forms I6 upon `which the finishing machine.' bridge or other machine may roll and be supported for carrying out the subsequent operations of pouring the concrete, spreading the conycrete, finishing, and practicing the steps of the improved method as hereinafter set forth.

The plastic concrete is shown generally at 69,

I and the various steps of preparing the subgrade,

pouring and nishing the concrete are more fully described in my co-pending application aforesaid.

In carrying out the improved method, there is placed on the subgrade, before the pouring of `the concrete, iafremovable shoveling vplatell, of

sheet metal or other suitable material; illustrated and described in my co-pending parent applicat te and method of installing expansion and contraction ljoint, as

tion heretofore referred to,

The shoveling plate Slt-is positionedv transversely of the roadway in the line of a proposed expansion or contraction Joint. The concreteY is then poured over y'this shoveling plate, and over the subgrade generallyfandl is spread and surfaced.

After the finishing machine has roughly surfaced' the plastic mass, the shoveling plate will be in position on the bottom of the'subgrade, as indicated at 88`A in Figure 1. In other words the shoveling plate will be covered by the superimposed mass of concrete forming part of the` continuous roadway.

While the concrete is still plastic, the plastic mass directly above the plate is shoveled or removed from the plate 88 and thrown up on each side of the plate which act will expose the shoveling plate, as indicated at 88-B in Figure 1, at which time the shovelingv plate may be lifted out of position. For this purpose the plate 88 has upstanding end flanges 89, which are bowed up centrally and provided with perforations 80 to rece ve the fingers, a hook or suitable tool for pull' g the plate out of the concrete. The flanges 89 and the upwardly bowed portions thereof serve to elevate the openings 98 to a position where it is convenient to grasp the same.

When the plate 88 is removed it will expose the 4subgrade of the roadway. as indicated at 88-C,

and the plate will have facilitated this operation, at the same time making it impossible to shovel clay, earth or other foreign matter from the subgrade to become undesirably mixed with the ooncrete.

An expansion joint or contraction joint is then placed on the subgrade, as indicated at 88-D in Figure 1, and the concrete is shoveled against the expansion joint and is spaded and tamped around the expansion joint or contraction joint, which may be of any conventional type, particularly that type of expansion joint in which is utilized short dowel bars with load transferring devices. Such joints are indicated in Figures 4 and 5.

Figure 4 shows an expanison joint which may be used and Figure 5 shows a desirable type .of contraction joint. Both of these types of joint, which will be understood by those skilled in the art, require a very narrow channel across the roadway in which to deposit the expansion joint usually not more than ten inches being required.

In Figure 4, 8| designates the plate or strip of an expansion joint, 92 is short dowel bars and 88 the load transferring devices. 4

In Figure 5l the contraction joint strip or plate 88 is shown as associated with the short dowel bars 85 and with the load transferring devices 88.

It will be appreciated by those versed in the art that heretofore expansion and contraction joints were'staked or otherwise secured to the subgrade prior to the placing of the concrete.

During the finishing operations, thatis due to the thrust of the finishing machine together with the surge of the mass of concrete against the expansion or contraction joints, the joints were often forced out of alignment. In addition, the dowel bars were often forced out of parallel position, which has been found to be detrimental.l The present method of placing the joints speeds the pouring of the concrete because of the placing of the joints back ofthe pouring and finishing operations. It has been found desirable to vibrate the concrete locally about the joints to insure perfect amalgamation and compaction of the concrete.

The flanges 88 may engage against the side forms I8, as shown in Figures 2 and 3, to assist in maintaining augment of the shoveling plates 88 against movement. l

Referring more particularly to Figure 6, therein is shown another method of producing the channel 88-C in the concrete by placing a series of containers 28 on the subgrade 2l. These containers are in a series transversely across the roadway from side form I6 to the opposite side form I6. Some of these containersare longer and deeper than others to form lateral depressions in the subgrade at a, depth below the common elevation of the subgrade; these depressions when filled with concrete form brackets or reinforcing elements to prevent slab curling, also to accommodate heavy load transfer devices to be installed. In depth the containers may be equivalent to the depth of the roadway, or a .layer thereof, which it is desired to build.

The containers may be submerged by the concretel as shown at 2Il-A. Immediately after the concrete has been spread and surfaced, the first time over, the boxes or containers 20 are lifted out of position, leaving the channel 88-C. 'I'he containers are filled with Athe plastic material of from the withdrawn containers 20 has been de- Dosited on the road surface.

After the containers 20 are removed from the road to produce the channel 88-C, dowel bars 82 together with a joint strip 9|', are positioned onthe subgrade and secured to alinement and .held in position by an alining bar 23, which is secured to the side forms I8 by cams or suitable clamping arrangement 24. The concrete is then thoroughly compacted and solidified or vibrated around the dowel bars and the joint by electrical or mechanical vibrators 23-A and the concrete thereupon receives its final surfacing treatment, as indicated at 28. After the compacting, surfacing and vibrating have been completed, the expansion joint, together with the dowel bars. are left installed as indicated at 28; it being understood that after the alining bar 23 has served its purpose, it is withdrawn and removed toa new point of' operation for repeated use.

Refening more particularly to Figures 7, 8, 9 and 10, a machine and method are disclosed for expediting the operation of joint installation, in which a corrugated receptacle )28, as shown in Figure 10, or in the modified form in Figure 11, to replace the shoveling plate 88 of Figure 1 or the series ofcontainers 28 of Figure 6.

The corrugated receptacle 28 is made of a length to extend all the way across the roadway between the side forms I8. This single receptacle 28 or 28A is placed upon the subgrade, as indicated at 28-B in Figure 7. lThe concrete 21 is then poured betweenthe side forms and into the receptacle and thereafter'surfaced over the roadway by a machine'moving in the direction of the arrow. This machine follows the pouring .and spreading operation and it comprises a traveling bridge or carriage 28 having wheels 28 rolling along the side forms I8.

On the bridge 28 is an elevated framework 88 for supporting hoisting tackle of any kind, for instance consisting of a drum 8i, an appropriate `quently positioned.

and 38 in the receptacle 26 or 26A. In this way the receptacles full of concrete, may be bodily lifted out of position as submerged in the concrete 21 in order to leave a channel in which the dowel bars 92 'and joint strip 9| are subse- Whle secured in such position on the subgrade, concrete is dumped from the suspended receptacle 26 over the dowel bars and expansion strip and into the channel, thus replacing the plastic material over the joint strip, and dowel bars. Platforms 39 on the bridge 28 are provided for workmen to manipulate the lifting apparatus and y to dump the receptacle. After dumping the receptacle is released from the hooks 36 for re-use in a repeating operation.

The machine is now moved forward by hand or ,under its own power until the vibrating apparatus is positioned over the joint material over the channel containing the joint materia1 as indicated at the left end-of Figure 7. The vibrating apparatus comprises the vibrators 40, the

strip or plate 4I and the forks or projections 42. The plate 4| forms a convenient, medium to support the vibrators 40 and to carry the projections 42. The plate is supported by screw shafts 43, swivelly connected at their lower ends with the plate 4I and threadedly engaged through nuts 44 carried in any suitable manner by the carriage or bridge 26.

By turning down the screws 43, the forks or projections 42 will be made to penetrate the concrete which has been redeposited by the upturned receptacle into the channel containing the dowel bars and joint strip. Such projections 42 will carry the vibratoryaction of the vibrators 40 into the concrete body to cause reuniting of the concrete particles and the kneading of the material so as to produce a dense homogeneous structure in which the redeposited concrete will become one with the body of the road.

rI he zig-zag walls of the receptacles 26 or load transfer devices and will also prevent slab curling.

It is obvious that various changes and modications may be made in the details of construction and design of .the bovespecically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restrictedonly `by the scope of the following claims.

What is claimed is:

1. The method of building concrete roads'which consists in pouring and surfacing concrete over a plate, removing the concrete from over the plate, removing the" plate to produce a channel, positioning an expansion joint and dowel bars to alignment within the channel, replacing the concrete, and compacting and` finishing the concrete over the expansion joint and 'dowels.

26-A, produced by the corrugations, will avoid the possibilityof developing planes of weakness adjacent the joint strip 9|. The vibrating apparatus isvarranged forvertical adjustment, for instance by the use of hand wheels 45. Electric power is provided by the power plant 46 mounted upon the carriage 28 and connected by a chain 41 and sprockets 48 and 49 with the wheels 29 or their axles. In this way the power plant 46 may drive the carriage 26, and at the same time through electrical cables 60 supply the necessary current to the vibrators 40. Dummy joints 5I, or other part depth joints may be installed by a similar method, or may be vibrated intoposition as disclosed in my prior patents already issued. Final surfacing of the concrete is done in a conventional way, Athus speeding production.

Referring back to Figure 7, the receptacles may or brackets, which serve as reinforcing elements along both sides of the abutting slabs to reinforce the slabs tol prevent fractures of the concrete transversely along or close to the joint when great pressure is exerted due to expansion of; opposing` 2. The herein described method for building.

' and installing joints in, plasticroads which con-v sists in dampening the subgrade, removing earth `and. other material from the dampened subgrade between the side forms down to a desired level. compacting thev subgrade and vibrating the same, laying plates on the subgrade in positions to be occupied by the transverse joints, pouring and surfacing plastic concrete over said plates and subgrade, removing the concrete from above the plates and lifting out the plates, installing joints in the channels lately occupied by the plates, re-

turning concrete in and about the joints and com,

pacting and vibrating the same.

l3. The herein described method of building, and installing joints in, roads formed of plastic material, which comprises insulating the plastic road material from the earth of the subgrades along predetermined strips, removing the plastic material from these predetermined strips without admixture of subgrade material, placing the joints in the channels formed by removal of the concrete, returning plastic material to the channels in and about the joints, `and compacting andi nishing the returned plastic material.

4. The herein described method for building, and installing joints in, roads formed of plastic material, consisting in placing side by side in a series across the roadway a number of containers. pouring plastic material on the subgrade and over said containers, removing the containers to produce a transverse channel, placing joint material in the channel, re-depositing plastic material in the channel and about the joint material, and surfacing and finishing the roadway above such re-deposited plastic and joint material,

5. The herein described method of preparing plastic roads under construction for joint maf terial, consisting in initially placing on the subgradea receptacle extending substantially across the roadway, pouring the plastic material in the normal manner on the subgrade and over and into such receptacle, raising the receptacle to produce a channel inthe plastic material roadway for the reception o f joint material, placing joint material in the channel and dumping the receptacle to re-deposit the withdrawn material into the channel in and about the joint material.

6. The method as herein described and claimed in claim 5, further consisting in vibrating the redeposited material in the channel in and about the joint material.

'7. The method of forming subgrade and ing stalling joints in concrete roadscomprising exfcavating of subgrade, placing in such excavaslabs; also these thickened edges along the transtions removable forming elements to mold formay tions in the subgrade, removing said elements.

placing. joints and load transfer elements in the formations and pouring concrete on the subgrade and into such formations, thereby forming reinforcing elements integral with the body of the mass of concrete to reinforce the concrete structure. adjacent to such joints and load transfer elements installed therein.

8. The method ofv installing joints yin plastic material of a road under construction comprising positioning containers on the sub-base along the l0 line of proposed joint, then pouring andv spreading the plastic material on the sub-base and in the containers, then removing the containers and the material therein and positioning Joint material and instrumentalities, including load transfer devices on the subgrade along the line of joint, then returning the plastic material to submerge the joint and said instrumentalities, then vibrating, compacting and finishing the material over said joint and instrumentalities.

JOHN N. HELTZEL.

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