AU2008201815A1 - Concrete screed - Google Patents

Description

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P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "CONCRETE SCREED" The following statement is a full description of this invention, including the best method of performing it known to me/us: 00 1

STITLE

"CONCRETE SCREED" c FIELD OF THE INVENTION This invention relates to a screeding device for plastic concrete.

The invention is particularly suitable for plastic low slump concrete but 00oo is not restricted to this application. The invention also extends to a method of c screeding plastic concrete.

oO 00 C 10 BACKGROUND OF THE INVENTION Concrete is the base ingredient for a vast range of structures and is used globally. In a typical concrete pour, plastic concrete is distributed into a space defined by formwork. In a horizontal pour such as for a slab, a road, a parking area or an airport, the pour is usually laterally confined between spaced parallel formwork members. Successive addition of more concrete to the previously laid plastic concrete leads to the longitudinal advancement of the pour. Concrete is most commonly delivered from mixing trucks and through a distribution chute or a concrete pump. The delivery of concrete between the formwork is, at best, approximate. Further processing requires semi-levelling of the plastic concrete followed by screeding to level and finish the surface of the material. Plastic concrete is most commonly distributed by workers using shovels or similar spreading devices. This is an ergonomic problem as well as requiring extensive input of labour to ensure the proper finish is applied prior to the concrete setting or becoming unworkable.

The problem of spreading is particularly pronounced in low slump concrete which is used in high integrity applications such as airfield landing strips, heavy load carrying roadways and similar applications. The low slump plastic concrete is particularly difficult to move due to its density and high viscosity. Further, it is a common requirement that workman do not step into the material in case they introduce imperfections such as dirt or vegetable matter thereby leading to potentially compromised strength of the final 00 2 C structure. Alternatively, it may be necessary to institute quality control 4 measures to ensure there are no contaminants on workers boots, with associated costs and inefficiencies.

c One example of low slump concrete arises in Defence Force airfields where heavy impact aircraft, such as Hercules tactical aeroplanes, land.

This concrete tends to be specified as 40/40/40 which is 40 millimetre 00oO aggregate, and 40 millimetre slump and 40 MPa strength as opposed to the N more common 20 millimetre aggregate, 80 millimetre slump with 20 MPa 00 oo strength (20/80/20).

C 10 This low slump material cannot be pumped. In a typical 700 square metre pour it is necessary to use around 12 manual labourers just to distribute and finish the material. With low slump concrete, it may be necessary to have 20 -25 men creating both a staffing and economic problem.

Use of prior art screeds will often lead to their deformation on low slump concrete, unless they are particularly robust and therefore large. This creates problems with transportability and utility in locations with limited access.

There have been many attempts to provide automated concrete screeding arrangements.

US Patent No 4,466,757 (Allen) provides a complex arrangement having a screed blade coupled to a screed frame which is vibrated. The concrete spreading device includes an auger or grading blade (or both) which is or are translated back and forth along the length of the screed frame. This is a relatively complex arrangement with significant moving components. It is potentially both expensive and prone to damage in the harsh environment in which it operates.

An engine driven vibrating screed is described in US Patent No 4,335,976 (Morrison). This arrangement also includes a hydraulically powered winch system for advancing the device.

US Patent No 3,377,933 (Dale) discloses a winch propelled road 00 3

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laying machine having a reciprocating rear-mounted screed and a frontmounted spreading auger.

US Patent No 2,583,108 (Lewis) describes a concrete spreader with N two spaced augers mounted on a carriage and laterally translatable with respect to the machine frame.

US Patent No 4,930,935 (Quenzi) discloses a pivoting screen 00 assembly which is self-propelled having a boom and boom mount and a pivot 0 N between the boom and the screed assembly. A power source rotates the 00 Oscreed about the pivot axis preferably in response to an electro-hydraulic levelling sensor mounted on the screed. A power operated elevation control is preferably responsive to a fixed laser beam reference plane positioned externally of the screed assembly. This is clearly a highly sophisticated and expensive machine.

US Patent No 5,288,166 (Allen) describes an automatic grading control device for finishing plastic concrete which is driven by a winch.

Hydraulic or pneumatic cylinders extending between the strut and the bridge raise and lower the tool thereby controlling level. The cylinders are controlled by a beacon laser and attendant sensors secured to the device. This is also a complex and expensive arrangement.

US Patent No 6,129,481 (Tapio) describes a screeding assembly and method for spreading loose or plastic material. The assembly includes a rotatable auger to move the material laterally across the path of travel. A vibratory screed is positioned behind the auger to smooth and finish the material and an elongated engaging member is reciprocated laterally across the path at a position between the auger and vibratory screed to facilitate consolidation of the material. A plough or striker may be positioned in front of the auger to remove excess material. The assembly is preferably mounted in a self-propelled vehicle or other support on a boom for moving the assembly over the material and is controlled by a laser beam responsive elevation control. This is also an expensive and sophisticated piece of equipment.

00 4 C There is a need for a relatively cheap, easily operated screeding e arrangement which can be used readily on site preferably utilizing at least some of the resources which are typically found on such a site.

c Reference to any prior art material in this document is not an acknowledgement that that material forms part of the common general knowledge in Australia or any other country.

00 c SUMMARY OF THE INVENTION 00 In one broad form, the invention resides in a concrete screed for use c 10 on plastic or uncured concrete, the concrete screed comprising: a support frame; one or more screed plates attached to a bottom of the support frame; and a spreader attached to the support frame and spaced forward of the one or more screed plates. The spreader may extend substantially the full length of the one or more screed plates.

The support frame may be any appropriate structure. It is preferably formed with a rectangular base. It may additionally or alternatively be formed as a braced triangular frame.

The support frame is desirably relatively light weight to enable easy manoeuvring on a work site.

The support frame may include a carriage positioned at each end for facilitating forward and backward movement in operation.

The support frame may further comprise a lifter for lifting the support frame and attachments up above a surface of the plastic or uncured concrete, particularly for reversing over the surface to re-screed it. The lifter may be multiple handles for manual operation. The lifter may be lifting points for engaging a powered vehicle.

Each carriage may include wheels and/or skids. Each carriage is preferably adapted to run along the top edge of formwork or adjacent an outer surface of such formwork, or along an adjacent surface such as a 00 Spreviously poured, cured slab.

e The one or more screed plates are preferably vibratory screed plates.

A vibratory power source may be mounted on the support frame and may Ccomprise one or more motors coupled to a drive shaft having one or more eccentric weights to induce vibration during rotation.

The concrete screed preferably has two spaced parallel screed plates oo being a first anterior plate and a second posterior plate. The screed plates 0 may comprise any suitable material such as a metal plate or beam.

oo SThe spreader may comprise a blade arrangement attached to the c 10 support frame preferably by one or more forward extending arms. The blade arrangement may be formed from modular components. An anterior surface of the spreader may be substantially planar or alternatively may be concave in vertical cross-section. The spreader's surface may be flat, V-shaped or concave in horizontal cross-section. The apex of the V-shape may be anterior or alternatively posterior. The surface may be any effective shape.

The spreader is preferably set slightly higher than the one or more screed plates. The difference may be in the range of 2 to 70 millimetres but preferably 5 to 20 millimetres.

In one embodiment, the spreader may be adjustable in its height relative to the screed plate or plates. The forward extending arms supporting the spreader may be pivotally fixed to the support frame with one or more adjusters such as rams, pneumatic or hydraulic, for altering height and a controller for varying the rams and hence the height of the arms and consequent height of the spreader. The adjusters may be cables or tubes with a turnbuckle intermediate the ends to effect variation of the length of the cables or tubes.

In one embodiment, the spreader is powered by a vibrating engine coupled to the spreader to effect vibration of the spreader. This may be mounted to a cross-beam.

The concrete screed may be built in modules to allow variation of the width. The concrete screed in one embodiment may be telescopic.

00 6 C The concrete screed may further include attachment points for one or e more cables which in turn may be attached to a traction source for advancement of the concrete screed. A particularly useful traction source is c a hydraulic power plant designed to power a wide range of attachments such as a DINGO® mini-digger. Other traction sources may also be utilised.

Preferably, the concrete screed includes one or more engagement 00oo for receiving a driving machine such as an earthmoving machine, a N mini-digger, a self-propelled machine or any suitable machine to propel the oo Sconcrete screed. The driving machine may be a DINGO®, Bobcat®, c 10 excavator or similar.

The concrete screed may also include a coupling arrangement to allow the driving machine to couple with the spreader directly or indirectly and lift the spreader. The arrangement may also facilitate lifting of the concrete screed. The coupling arrangement may therefore form a lifter.

In a preferred form, the concrete screed includes an engagement section at each end adapted to couple with a corresponding propelling machine. The engagement section may comprise a laterally extending arm, a universal joint fitted to the arm and a housing fitted to the universal joint and adapted to engage the propelling vehicle. The universal joint may be a pin positioned through an oversize aperture in one arm. The housing may be a shoe adapted to receive a bucket, blade or hydraulic arm of the propelling vehicle. In an alternative form, the engagement section may comprise arms extending laterally. Other arrangements for receiving a propelling vehicle may be used.

The screed may further include scrapers, preferably rubber, positioned to clean the track ahead of each carriage.

The concrete screed is preferably collapsible or disassemblable into easily transportable components and may be produced in kit form.

In one arrangement, the spreader is attached to a cross-beam extending laterally beyond either end of the screeding plates and adapted to form or support the engagement sections.

00 7 C In a further aspect, the invention may reside in a method of spreading e plastic concrete, the method comprising the steps of: a) distributing excess uncured concrete with a spreader attached Canteriorly to a support frame, the excess concrete spread to a level slightly above a finish level; b) screeding the plastic concrete with a screed plate attached to 00 the support frame and trailing the spreader wherein: C the spreader extends substantially along the full length of the 00 Sone or more screed plates.

c 10 Preferably, the method includes advancing the concrete screed with one or more independent self-propelled vehicles. This step may include engaging the one or more independent vehicles with corresponding engagement sections on the concrete screed.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the various aspects of the invention may be readily understood and put into practical effect, reference will now be made to preferred embodiments illustrated in the accompanying drawings in which:- FIG. 1 is a top plan view of a first embodiment of the present invention; FIG. 2 is a front view of the embodiment of FIG. 1; FIG. 3 is a three-dimensional view of the arrangement of FIG. 1; FIG. 4 is a top schematic view of the above embodiment in operation on a concrete pour; FIG. 5 is a top plan view of a second embodiment of a concrete screed of the present invention; FIG. 6 is a front view of the embodiment of FIG. FIG. 7 is a perspective view of the embodiment of FIGS 5 and 6 in operation.

FIGS 8 and 9 are side views of screeds with alternative carriage arrangements; and 00 8 FIG. 10 is a front view of a third embodiment of a screed of the 4 present invention.

C DETAILED DESCRIPTION OF THE DRAWINGS Referring to FIG. 1 there is seen a concrete screed 10 connected to two small self-propelled machines 12,14.

oo 0 The concrete screed 10 has a support frame 16 with an anterior N screed plate 18 and posterior screed plate 19 attached to the bottom of the 00oo 0frame. While a frame structure is preferred for reducing weight it should be c 10 understood the expression "support frame" may extend to a continuous housing or plate construction.

A vibrator 20 is provided as an engine which drives shaft 21 with an eccentric weight 22 to thereby vibrate the frame and screed plates.

End plates 23, 24 are provided on the frame 16 and may be dimensioned to slide along edged formwork on a concrete pour. A bottom surface of the end plates 23,24 may be concave to permit sliding along the top of the formwork. Alternatively, wheels or a carriage may be provided to engage the ground or the top of the formwork. The carriage may be in part formed integrally with the frame and may incorporate an endplate. The carriages are positioned at each end of the screed.

The end plates 23,24 extend anteriorly to engage a cross-beam which is substantially parallel to the screed plates 18,19.

The cross-beam 25 extends outwardly beyond the end plates 23,24 to provide machine engagement sections 27,28. The cross-beam 25 supports a spreader which in this example is in the form of a blade 30 with a gentle concave curve in top plan view. Other shapes may be used.

The blade 30 is attached to mounts 31,32 which accommodate its curve.

Lifters 33,34 are provided to allow differential movement of the blade 30 relative to the screed plates 18,19. The lifters may be any suitable arrangement such as a screw-thread adjustment to allow vertical sliding of 00 9 C the blade relative to the cross-beam 25. Alternatively, the lifters may be a e hydraulic or pneumatic ram or other suitable arrangement known to a person skilled in the art. Typically, the bottom of the blade 30 is positioned slightly Chigher than the screed plate or plates. The difference will vary with the application. A typical range may be 2 millimetres to 70 millimetres. A preferred range with low slump concrete is 5 millimetres to 20 millimetres.

0 In one embodiment, there are no lifters and the blade is simply set in C a permanent position relative to the screed plates.

00 SIn a further embodiment, the cross-beam 25 and blade 30 may be c 10 pivotably attached to the end plates so that hydraulic arms on the selfpropelled machines 12,14 may be used to vary the height of the blade relative to the screed plates when the support frame is positioned on formwork.

Considering now the self-propelled machines 12,14, a particularly suitable form of such machines which is commonly available on worksite is a mini-loader known as DINGO® available from Dingo Australia in Dalby, Queensland.

This machine has a hydraulic power plant designed to power a wide range of attachments and is small, self-propelled and operated by an operator who stands on or walks behind the machine. The device has two separate pumps which deliver up to 47 litres per minute of hydraulic power at up to 3400 p.s.i. Dingoes may have up to sixty attachments for different applications on worksites. They are therefore highly utilitarian, in demand and as a result common. The Dingo may be little as 760 mm wide and therefore is usable in places where previously only hand labour could operate. It may also be easily transported on a trailer. The DINGO® is merely generically representative of the type of machine that may be used.

Larger vehicles such as bobcats may be useful in appropriate circumstances.

The utility of the present invention is readily apparent.

In one preferred form, the concrete screed may be demountable with adjacent pieces interconnected by bolts and nuts or other couplings. The 00

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C concrete screed may be built up on a job site and may be easily transported e to a level in a high-rise building for example, or into other difficult to access points. It is also easily transported in its dissembled state. On site it may be N assembled and then used with a readily available tractor source such as a Dingo. Other machines of course may also be used. An end loader, backhoe or forklift for example may be used. The concrete screed may also be (0 adapted to be drawn forward by a power source, a winch or similar.

C The end plates 23,24 are attached by triangulated chains 35,36 to the 00 Smachines to provide lateral stability. Hydraulic arms 37,38 of the vehicle are c 10 engaged with machine engagement sections 27,28 via pads 39,40. This may include a loose engagement such as under the effects of gravity.

Alternatively, there may be positive engagement such as with nuts and bolts.

A front view is seen in FIG. 2 where the vibrator 20 is positioned midway along the frame 16 although this position can be varied. The support frame 16 has an upward arching top line 41 and vertical struts 42. Other configurations may be suitable.

The blade 30 is apparent and positioned slightly above the anterior screed plate 18 and the posterior screed plate (not visible). The spreader therefore smooths out a layer of concrete and moves excess material forward. The smoothed layer is then slightly above the formwork and level of the screed plates which vibrate and work the plastic concrete and compress it down to the level of the formwork, being the desired level.

Handles 43,44 are provided for manual lifting and transfer of the concrete screed or support frame. This enhances the manoeuvrability of the device which may be quite lightweight but at the same time strong. The vibrator 20 may be also demountable to allow easy transfer of the components.

FIG. 3 is a schematic view of the arrangement of FIG. 1 with the blade applied to the cross-beam 25. Engagement pads 45,46 are attached to the cross-beam 25 and adapted to receive the arms 38,37 of the selfpropelled machines 12,14. Alternatively the bucket of the machines 12, 14 00 11 c may be slotted into the pads 45, 46 to lock under lips 47, 48. The 4 engagementpads 45,46 have a lip 47,48 adapted to allow the machines to lift the anterior part of the arrangement and modify its height relative to the c screed plates 16,18 if it is pivotally attached.

In one embodiment, the cross-beam may be pivotally such as by arms attached to the frame so that the relative height of the blade to the screed 00oO plate may be varied.

c In an alternative embodiment or in the same embodiment, the crossoO 00 Sbeam 25 may be fixed relative to the support frame 16 so that the machines c 10 can be used to lift the front of the assembly while operators may manually grasp one or more of the handles 43 and the corresponding handles on the near side (not visible) so that the whole assembly may be moved backwards over a screeded section for re-screeding. Reinforcing braces 47 are also apparent.

In a preferred embodiment, the blade 30 is also subject to vibration.

This may be indirectly from the previously described or central vibrator.

Alternatively, there may be a second vibrator applied to arms supporting the cross-beam or a platform between the support frame 16 and cross-beam A vibrator 60 (shown schematically) is applied directly to the crossbeam for vibrating the spreader.

FIG. 4 is a top schematic view of a concrete pour in which a concrete truck 50 distributes plastic concrete from a rotatable discharge chute 51 between parallel formwork walls 52,53. A bridge 54 is mounted over the concrete pour and formwork and allows operators 55,56 to do an initial rough working of the concrete without standing in the mixture. This is particularly important in low slump high integrity concreting jobs where the risk of contamination must be minimised.

After initial settling, the concrete screed 10 of the present invention is advanced in the direction of arrow 57 with the blade 30 corresponding to the width of the pour and conducting an initial distribution and levelling of the plastic concrete.

00 12 0 C- The vibrating screen plates 18,19 then travel over the roughly levelled Sconcrete and compact the slab to its final level and finish the surface.

The present invention may include an ability to mount modular N extensions to one or both ends of the concrete screed. These may be bolted on. Given the ability to dissemble one embodiment of the invention, the addition of these extensions is well within the knowledge of a person 00oo skilled in the art.

C The concrete screed is preferably formed from a metal or alloy. Light oo 00 0 gauge steel or aluminium may be suitable for the frame with steel plates for c 10 the screed plates and spreader.

Referring to FIG. 5 there is seen a concrete screed 110 of a second embodiment of the present invention. The concrete screed has a support frame 116 supporting three vibrator motors 120 spread across the length of the frame. The end plates 123, 124 are formed as substantial beam members which also space the blade 130 and screed plate 119. The end plates 123, 124 support corresponding laterally extending arms 150, 151 respectively. Engagement sections are exemplified by the arms 150, 151 corresponding universal joints 152, 153 and plates adapted as shoes 154, 155. The shoes are formed to receive a blade bucket or the arms of a propelling machine such as a Dingo. The universal joint provides rotation of the shoe around a vertical axis and also allows for some degree of rotation around a horizontal axis. Braces 157, 158 are provided with adjustable threaded sections to tension the device especially when it is formed in a kit or collapsible embodiment. V braces 159, 160 and 161, 162 are formed at each end of this concrete screed. In one embodiment the blade and screed plate or plates are adjustable relative to the frame. Tightening or loosening of the V braces will adjust the relative position of the spreader and/or screed plate or plates relative to the side carriages and frame therefore allowing for slight variation at each to accommodate irregularities in a surface. In the present embodiment, the V braces serve as a static bracing arrangement.

The propelling vehicle may be attached to the screed by a coupling 00 13 N arrangement such as the shoe of the engagement section, or a lipped plate.

FIG. 6 shows a front view of the embodiment of FIG. 5. The end plates 123, 124 support the arms 151,150 and the V braces attached to a c butt inner end of the arms. The upper line 141 and vertical struts 142 are apparent.

This embodiment has central removable module 170 formed along 00oo breaks 171, 172 so that the central module and associated vibrator 120A C may be removed. Different sized central modules may be introduced to vary oO 00 Sthe width of the concrete screed as desired. The spreader may be formed as C 10 a continuous blade.

FIG. 7 shows the arrangement of FIGS. 5 and 6 in operation. Dingoes 112, 114 couple with the engagement sections formed by arms 150, 151, universal joints 152, 153 and shoes 154, 155. The function of the universal joints 152, 153 is more apparent in this view as they are formed from a pin in an oversized aperture formed through the respective arms. This allows some movement of the show around a vertical and partially around a horizontal axis. This view clearly shows the carriages 181,182 are formed at each end of the screed. In this case the carriages have wheels 183 but it is clear that other arrangements such as a skid or similar may be used to support the screed. Also apparent in this view is the lateral arms 151,150 fixed centrally to the end plates 123, 124 as compared to the earlier embodiment.

This view also shows a scraper 184 fixed to either side of the carriage to clear the track of the wheels. The scraper may be formed as a downwardly descending tongue or rubber or other resilient material. A concrete pour 185 is apparent behind the screed which runs down formwork 186.

FIGS 8 and 9 show side views of alternative embodiments of carriages 190, 191, The first formed with wheels 192 and the second with skids 193. In a simple form, the skids may be the base of the side plates.

Arm 151 is seen in end view and the scraper 184 is also apparent and aligned with the blade 194.

FIG. 10 shows the arrangement of FIG. 6 when the central module 00 14 N has been removed. Concrete screed 210 is formed by the first outer module e 211 and second outer module 212. The vertical struts 142 are now adjacent with angled top line struts 141 extending outwardly. Break 213 is apparent 1 with plate lockers 214 fixed in position and holding the blade 130 in place.

A particularly preferred version of the blade is formed from hardened steel. The blade may extend beyond the concrete bay. An extended 00oo of about 200 mm may be suitable. The cross-beam with machine N engagement capacity may extend around 2 metres past each end of the oo Sconcrete bay, but may vary with the particular indication.

S 10 The present invention is particularly well suited to low slump concrete where movement of the material requires intense physical effort by operators with resultant risk of poor final result and, more importantly, injury to the operators. However, the concrete screed is not so restricted and may be used in a wide variety of concrete pour environments.

The device may be easily cleaned, dissembled and transported. It has a long serviceable life. It is relatively cheap to build or buy and uses available resources on a job site in its operation. It is therefore of particular economic benefit to smaller operators.

The advantages include less risk to the knees and backs of concrete workers historically, both anatomical areas of greatest damage. The present invention also allows an increased speed to place and finish concrete with associated cost savings and enhanced quality.

It should be appreciated that various other changes and modifications may be made to the embodiments described without departing from the spirit or the scope of the invention.

Claims (21)

1. A concrete screed for use on plastic or uncured concrete, the c concrete screed comprising: a support frame; one or more screed plates attached to a bottom of the support frame; o00 a spreader attached to the support frame and spaced forward of the 0 C one or more screed plates and adapted to spread excess plastic or uncured 00 oo concrete; and, c 10 one or more engagement sections for receiving a driving machine to propel the concrete screed.

2. The concrete screed of Claim 1 wherein the support frame further comprises a lifter for lifting the concrete screed up above a surface of the plastic or uncured concrete.

3. The concrete screed of Claim 1 further comprising a carriage positioned at each end of the support frame for facilitating forward and backward movement in operation, the carriage including wheels and/or skids.

4. The concrete screed of Claim 1 wherein the screed plates are vibratory screed plates.

5. The concrete screed of Claim 1 comprising two spaced parallel screed plates being a first anterior plate and a second posterior plate.

6. The concrete screed of Claim 1 wherein the spreader comprises a blade arrangement attached to the support frame by one or more forward extending arms.

7. The concrete screed of Claim 1 wherein the spreader is set higher than the one or more screed plates in the range of 2 to

8. The concrete screed of Claim 6 wherein the spreader is supported by forward extending arms which are pivotally fixed to the support frame with one or more adjusters for altering height of the spreader.

9. The concrete screed of Claim 1 wherein the spreader is activated by a vibratory engine coupled to the spreader to affect vibration of 00 16 N the spreader.

The concrete screed of Claim 1 further including attachment points for one or more cables which may be attached to a traction source for c advancement of the concrete screed.

11. The concrete screed of Claim 1 further including a coupling arrangement to allow the driving machine or machines to couple with the oo spreader directly or indirectly and lift the spreader. c

12. The concrete screed of Claim 1 comprising an engagement 00oo Ssection at each end of the concrete screed, each engagement section c 10 adapted to engage a corresponding driving machine.

13. The concrete screed of claim 1 where the one or more engagement sections include laterally extending arms.

14. The concrete screed of either Claim 1 or Claim 12 wherein each engagement section comprises a laterally extending arm, a universal joint fitted to the arms and a housing fitted to the universal joint and adapted to engage the propelling machine.

The concrete screed of Claim 14 wherein the universal joint comprises a pin positioned through an oversize aperture in the arm.

16. The concrete screed of Claim 15 wherein the housing is formed as a shoe adapted to receive a bucket or blade of a propelling machine.

17. The concrete screed of Claim 16 further including a scraper on each end, the scraper positioned to clean a track in advance of each carriage.

18. The concrete screed of any one or the preceding claims wherein the concrete screed is collapsible or disassemblable into easily transportable components.

19. The concrete screed of Claim 1 further including adjusters for adjusting the position of the one or more screed plates and the spreader in relation to one or both sides of the support frame.

20. A method of spreading plastic concrete, the method comprising the steps of: 00 17 distributing excess uncured concrete with a spreader attached anteriorly to a support frame, the excess uncured concrete spread to a level slightly above a finished level; C screeding the plastic concrete with a screed plate or plates attached to the support frame and trailing the spreader; and advancing the concrete screed with one or more independent 00 self-propelled vehicles. c

21. A concrete screed is claimed herein with reference to the 00 figures. c