Abstract:
A rotating cylinder cement screeding system having a drive assembly and handle at one end for powering and controlling the screeding system. The rotating cylinder may be defined by one or more tubular screed roller sections of varying lengths, thereby allowing a user to customize the length of the system to match a specific cement pour. Further, each tubular screed roller section may be supplied with a male and female end for interlocking with each other and for receiving a variety of add-on attachments. At least one riser assembly may be interconnected to a drive assembly end and/or a non-driven end of the rotating cylinder cement screeding system. The riser assembly may elevate the rotating cylinder a distance above a finished slab to prevent the rotating cylinder from contacting the finished slab during a screeding operation.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application is a divisional of, and claims priority to, U.S. patent application Ser. No. 12/357,837 (now U.S. Pat. No. 8,137,026), that is entitled “POWERED ROLLER SCREED WITH RISER WHEEL,” and that was filed on Jan. 22, 2009, which is a non-provisional application of U.S. Provisional Patent Application Ser. No. 61/145,838, that is entitled “POWERED ROLLER SCREED WITH RISER WHEEL,” that was filed on Jan. 20, 2009. The entire disclosure of both of these patent applications is hereby incorporated by reference in their entirety herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention generally relates to the leveling of materials such as wet or recently poured concrete and, more particularly, to attachments for a powered roller screed. 
     BACKGROUND 
     Concrete may be poured between a pair of forms, between a pair of existing, hardened concrete slabs, between a form and an existing, hardened concrete slab, or the like. Once the concrete is poured, it may be leveled and compacted by a process known as “screeding.” Various types of screeding devices have been used over time. 
     A basic screeding device may be a simple 2×4 or some other elongate member. One or more workers would place the 2×4 on the forms and pull/slide the 2×4 along the forms to screed the poured concrete. While this manual technique may work to at least some degree for at least smaller jobs (e.g., short sections of sidewalk), there are a number of deficiencies. One of course is that this technique is very labor intensive and physically demanding. This type of screeding is also not very effective at distributing and compacting the concrete within the forms, thereby potentially producing a finished concrete slab of a lesser quality than may be desired. 
     Truss screeds also exist, and tend to be used for larger jobs. The concrete is leveled off with an elongated truss. One or more internal combustion engines or the like may be mounted on the truss to vibrate the truss to enhance the screeding. Typically one or more winches are incorporated into the truss to advance the same along the forms. Both manual and motorized winches exist for truss screeds. 
     Another type of powered screed is a powered roller screed. The powered roller screed generally consists of a screed roller (e.g., an elongated tube) that is rotationally driven by an attached motor. In operation, the screed roller is positioned over the poured concrete with each end of the screed roller positioned on the upper edges of the laterally-spaced forms. The screed roller is then moved along the top of the forms in a direction that is opposite to the rotational motion of the screed roller at its point of contact with the concrete. Usually one worker pulls on one end of the powered roller screed, and another worker pulls on the opposite end of the powered roller screed. Powered roller screeds produce a smooth and flat finish to the concrete. 
     SUMMARY OF THE INVENTION 
     A first aspect of the present invention is embodied by a powered roller screed having a screed roller and a drive assembly that interacts with the screed roller to rotationally drive the screed roller. At least two handles may be interconnected with the screed roller to allow at least two workers to exert a pulling force on the screed roller as it is being rotated by the drive assembly. In any case, a first riser wheel is appropriately interconnected with the screed roller. The outer diameter of the first riser wheel is larger than the outer diameter of the screed roller. Moreover, the first riser wheel and screed roller are rotationally independent from each other. 
     A number of feature refinements and additional features are applicable to the first aspect of the present invention. These feature refinements and additional features may be used individually or in any combination. As such, each of the following features that will be discussed may be, but are not required to be, used with any other feature or combination of features of the first aspect. The following discussion is applicable to the first aspect, up to the start of the discussion of a second aspect of the present invention. 
     Each handle for the powered roller screed may be of any appropriate size, shape, configuration, and/or type (e.g., a rigid member, a flexible member, a rope, a strap, a tether, a chain). Any appropriate way of interconnecting each handle with the screed roller may be utilized that allows the screed roller to rotate relative to each such handle (e.g., each handle may be rotationally isolated from the screed roller). First and second handles may be spaced along the length of the screed roller. One handle may be associated with the drive assembly (e.g., extending from a frame that supports a motor of the drive assembly). In one embodiment, one handle is associated with one end portion of the screed roller, and another handle is associated with an opposite end portion of the screed roller. 
     Any appropriate power source may be utilized by the drive assembly. For instance, the drive assembly may utilize one more motors of any appropriate type. Representative motors that may be used to rotate the screed roller include without limitation an electric motor, an internal combustion engine, and the like. In one embodiment, the screed roller is rotated at a relatively high velocity (e.g., at least 100 RPM, and commonly 300 RPM) and in a direction that attempts to advance the screed roller in the opposite direction that the same is pulled during a screeding operation. 
     The screed roller may be of any appropriate size (e.g., length), shape (e.g., cylindrical), and/or configuration. The screed roller may utilize a single cylindrical structure or tube. In one embodiment, however, the screed roller is defined by detachably interconnecting two or more separate screed roller sections in end-to-end relation (e.g., via a threaded connection between each adjacent pair of screed roller sections). Any appropriate number of detachably interconnected screed roller sections may be utilized to define a screed roller of a desired/required length. “Detachably interconnected” means that individual screed roller sections may be repeatedly joined and separated, or vice versa, as desired/required (e.g., joined for a screeding operation at a job site; separated or disassembled for transport and/or storage). 
     A rotational axis of the first riser wheel may be coaxial with a rotational axis of the screed roller. There may be a first bearing between the first riser wheel and the screed roller (e.g., such that the first riser wheel is able to rotate relative to the screed roller). The first riser wheel may be a free-spinning structure, while the screed roller is rotatably driven. In one embodiment, the first riser wheel and the screed roller rotate in opposite directions during screeding. 
     The first riser wheel may be positioned between a first end of the screed roller and the drive assembly. A coupling (e.g., drive socket) that interconnects the drive assembly and the screed roller (e.g., to transport rotational power to the screed roller) may extend through the first riser wheel (e.g., where the first riser wheel may rotate relative to this coupling). The first riser wheel may also be interconnected with what may be referred to as a non-driven or non-powered end, or the end of the screed roller that is opposite the end where the power is input to the screed roller. In one embodiment, the rotational axes of the first riser wheel and screed roller are coaxial and the first riser wheel is disposed beyond an end of the screed roller. 
     The first riser wheel may have an outer diameter that is larger than the outer diameter of the screed roller by any appropriate amount, such as ¼″ or ¾″ (to provide a ⅛″ or ⅜″ gap, respectively, between the screed roller and the surface on which the first riser wheel is disposed). In one embodiment, the outer diameter of the first riser wheel is defined by an outer bearing race. In another embodiment, the outer diameter of the first riser wheel is defined by an outer ring that is appropriately mounted on the outer bearing race. In any case, the first riser wheel may be disposed on a concrete slab that is hardened to at least a degree so as to dispose and maintain the screed roller in spaced relation to this concrete slab when screeding poured concrete adjacent to the concrete slab (e.g., the concrete slab being used as a form). 
     A single riser wheel may be utilized by the powered roller screed (e.g., to dispose the screed roller at an incline relative to horizontal during a screeding operation, for any appropriate purpose). Multiple riser wheels may be utilized by the powered roller screed as well. Two riser wheels could be interconnected with the screed roller, where these riser wheels are of a common outer diameter (e.g., to dispose the screed roller, more specifically its rotational axis, in at least substantially horizontal relation), or of different outer diameters. The various features discussed above with regard to the first riser wheel are equally applicable to such a second riser wheel, individually or in any combination. 
     In one embodiment, one riser wheel is disposed beyond one end of the screed roller and another riser wheel is disposed beyond the opposite end of the screed roller. In any case, the first riser wheel may be disposed on a first concrete slab that is sufficiently hardened, a second riser wheel may be disposed on a second concrete slab that is sufficiently hardened and spaced from the first concrete slab, all so as to dispose and maintain the screed roller in spaced relation to each of the first and second concrete slabs when screeding concrete that has been poured between the two concrete slabs (e.g., each concrete slab being used as a form). Each such riser wheel may rotate at a speed that is dependent upon the linear speed that the screed roller is being pulled (e.g., the linear speed that the rotational axis of the screed roller is being moved by the operator(s) of the powered roller screed and relative to an upper surface of the first and second concrete slabs). 
     A second aspect of the present invention is embodied by a cement screed system. The cement screed system may generally include a screed roller and a drive assembly. The screed roller may have a first end and a second end. The drive assembly may be interconnected to the screed roller and operable to rotate the screed roller. The cement screed system may also include at least one riser assembly that is at least partially rotatable relative to the screed roller and drive assembly. The riser assembly may be operable to elevate the portion of the screed roller that makes contact with freshly poured concrete a distance above a finished concrete slab. Among other advantages, elevating the screed roller a distance above a finished concrete slab can prevent marring or scratching of the finished concrete slab by the rotating screed roller, facilitate the pulling of the cement screed system over the finished and freshly poured concrete surfaces, and allow operators to level the freshly poured concrete surfaces at elevations above the finished slabs and/or create inclined surfaces relative to the finished slabs. 
     In an embodiment, the screed roller of the cement screed system may comprise a plurality of individual, removable screed roller sections that are interconnected in any appropriate manner. For instance, the screed roller sections may be attached to each other through threaded connections at the ends of the individual screed roller sections (e.g., each screed roller section may have a threaded male member on one end and a threaded female member on its opposite end), although multiple screed roller sections may be detachably interconnected in any appropriate manner. Each of any screed roller sections may be of any appropriate length. Two or more of multiple screed roller sections that define the screed roller may be of different lengths, although such may not be the case in all instances. The overall length of the screed roller may be varied by removing and/or adding at least one screed roller section. Notwithstanding the foregoing, the screed roller could be in the form of a single screed roller section (e.g., the screed roller need not be defined by multiple screed roller sections). 
     In an embodiment, the drive assembly may be interconnected with the screed roller at least generally adjacent to the first end and in any appropriate manner. The drive assembly may be of any appropriate size, shape, configuration, and/or type (e.g., an electric motor, a gasoline engine). In one embodiment, the drive assembly is detachably interconnected with the screed roller. In one embodiment, the drive assembly includes a handle or the like to allow an operator to grasp the same and exert a pulling force on the screed roller. 
     In an embodiment, the cement screed system may include a bracket interconnected to the screed roller at least generally adjacent to the second end of the screed roller (e.g., disposed at or closely spaced from the second end). The bracket may be interconnected to the screed roller via a bearing such that the screed roller is free to rotate relative to the bracket. The cement screed system may include a handle assembly of any appropriate configuration for controlling the second end of the screed roller. The handle assembly may include a frame (e.g., one or more substantially rigid members that may be appropriately interconnected) and a first handle. The frame may be appropriately interconnected to the bracket (e.g., detachably). The handle assembly may also be in the form of a rope, strap, or the like. The handle assembly may allow an operator gripping the handle assembly to move the second end of the screed roller in at least one direction (e.g., to pull on the screed roller to move the same in a direction that is opposite to the direction that the screed roller is being biased by its rotation). The handle assembly may allow the operator standing in front of the path of the screed roller to move the second end of the screed roller in a backward or forward direction, as well as up or down. The handle assembly may further include a second handle interconnected to the frame. The first and second handles may be positioned such that an operator controlling the second end of the screed roller may grasp one such handle in each hand. 
     The various features addressed in relation to the first aspect may be used by the second aspect, or vice versa, and individually or in any combination. Any feature of any of the various aspects of the present invention that is intended to be limited to a “singular” context or the like will be clearly set forth herein by terms such as “only,” “single,” “limited to,” or the like. Merely introducing a feature in accordance with commonly accepted antecedent basis practice does not limit the corresponding feature to the singular (e.g., indicating that a powered roller screed includes “a riser wheel” alone does not mean that the powered roller screed includes only a single riser wheel). Moreover, any failure to use phrases such as “at least one” also does not limit the corresponding feature to the singular (e.g., indicating that a powered roller screed includes “a riser wheel” alone does not mean that the powered roller screed includes only a single riser wheel). Finally, use of the phrase “at least generally” or the like in relation to a particular feature encompasses the corresponding characteristic and insubstantial variations thereof (e.g., indicating that a screed roller is at least generally cylindrical encompasses the screed roller actually being cylindrical). 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a perspective view of an embodiment of a powered roller screed that illustrates the manner in which it may be deployed to finish a slab of concrete. 
         FIG. 2  is a top elevation view of a drive assembly for the powered roller screed of  FIG. 1 . 
         FIG. 3  is an end elevation view of the drive assembly of  FIG. 2 . 
         FIG. 4  is a front elevation exploded view of drive motor and drive plate assembly components of the drive assembly of  FIG. 2 , illustrating the manner by which they may engage the screed roller. 
         FIG. 5  is a front elevation view of a screed roller for the powered roller screed of  FIG. 1 , illustrating its general manner of construction and a way two or more individual screed roller sections can be joined together to form a longer screed roller. 
         FIG. 6  is a front elevation view of a plurality of screed rollers, illustrating the varying lengths in which they can be constructed. 
         FIG. 7  is a cross-sectional view of a connection between two adjoining individual screed roller sections. 
         FIG. 8  is a front elevation view of a footing member component that may be used by the powered roller screed of  FIG. 1 . 
         FIG. 9  is a cross-sectional view of the footing member component from  FIG. 8 . 
         FIG. 10  is a perspective view of an embodiment of a powered roller screed that illustrates the manner in which it may be deployed to screed concrete that has been poured between a pair of concrete slabs. 
         FIG. 11  is a perspective front view of a drive assembly end of the powered roller screed of  FIG. 10 . 
         FIG. 12  is a front elevation view of the drive assembly end of the powered roller screed of  FIG. 10 , which includes a riser assembly, and illustrating a gap created by the riser assembly between a lower portion of the screed roller and a concrete slab on which the riser assembly is disposed. 
         FIG. 13  is an exploded view of the drive assembly end of the powered roller screed of  FIG. 10 . 
         FIG. 14  is a perspective view of a non-powered or non-driven end of the powered roller screed of  FIG. 10 . 
         FIG. 15  is an enlarged, exploded, perspective view of the non-powered end of the powered roller screed of  FIG. 10 . 
         FIG. 16  is another exploded, perspective view of the non-powered end of the powered roller screed of  FIG. 10 . 
         FIG. 17  is another perspective view of the assembled non-powered end of the powered roller screed of  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the drawings, and more specifically initially to  FIGS. 1-3 , a powered rotational screed apparatus or powered roller screed  10  has a screed roller  12  that is adaptable to accommodate any number of specialized concrete slab pouring applications. The powered rotational screed apparatus  10  is designed generally to facilitate the finishing process in relation to the formation of concrete slabs. In the accomplishment of this process, the powered rotational screed apparatus  10  may be deployed on a slab pour site in a manner so that its screed roller  12  comes into contact with both the upper surfaces of the concrete forms  14  and the unfinished concrete  16  contained therein. This is accomplished by placing the screed roller  12  between the concrete forms  14  and over the area where the slab is to be formed. 
     One end or end portion of the screed roller  12  is rotationally attached to a drive assembly  20  and the other end or end portion to a pull device  22  (e.g., a handle) of any appropriate type (e.g., a strap, rope, or the like). The drive assembly  20  is the component of the powered rotational screed apparatus  10  that houses a drive motor  24 , which in turn provides the rotational power to operate the powered rotational screed apparatus  10  (more specifically to rotate the screed roller  12 ). The drive motor  24  is fixed within the drive assembly  20  by the use of a motor frame  36 , that also provides the point of fixed attachment for a handle assembly  26 . The handle assembly  26  extends upward through an extension bar  28  from the motor frame  36  to position a control grip or handle  30  and a pull grip or handle  32  in a position so that the entire handle assembly  26  can be easily controlled by an operator. Finally, the power to the drive motor  24  is supplied through a power cord  42  by way of the control handle  30 . The drive motor  24  may also be powered by an appropriate “on board” battery, an internal combustion engine (not shown), or any other appropriate power source. 
     The other end, or the non-powered or non-driven end, of the screed roller  12  (e.g., the end of the screed roller  12  that is opposite of the end where rotational power is input to the screed roller  12 ) provides the point of attachment for the pull device  22  through the operation of a pull bearing assembly  84 . The pull bearing assembly  84  operates to isolate the pull device  22  from the rotational aspects of the screed roller  12 , allowing it to be interconnected to the pull device  22  while allowing the screed roller  12  to rotate relative to the pull device  22 . The nature and manner of operation of the pull bearing assembly  84  will be described in greater detail below with reference to other possible components of the powered rotational screed apparatus  10 . 
     Additionally, the handle assembly  26  of the powered rotational screed apparatus  10  may be equipped with a pivotally mounted stand  34 . The stand  34  allows the drive assembly  20  to be left in an upright position when not in use so that the control and pull handles,  30  and  32 , respectively, are in an easily accessible location. When not in use, the pivotal attachment of the stand  34  allows it to be pivoted or rotated up next to the extension bar  28  so that it is not in the way during the operation of the handle assembly  26 . 
     To perform the finishing or screeding operation, the drive motor  24  is engaged by the use of the control handle  30 , which in turn powers the screed roller  12 . As the screed roller  12  spins, the operator of the drive assembly  20  and the operator of the pull device  22  move the powered rotational screed apparatus  10  in a direction that is opposite to the rotation of the screed roller  12  over the unfinished concrete  16 . This action has been found to be effective in producing the desired finish on the upper surface of the finished or screeded concrete  18 , while also causing the concrete to compact to a desired consistency. 
     The output of the drive motor  24  is configured so that it can be fitted to a drive socket  38 , which may be of a common 6-point impact type as illustrated in  FIG. 4 . As the drive socket  38  passes through the motor frame  36 , the drive socket  38  is encased by a socket bearing  40 . The socket bearing  40  allows the drive socket  38  to spin with the drive motor  24 , while securely holding it within the stationary motor frame  36 . 
     The use of the drive socket  38  allows for the securement of a drive plate assembly  52 , which in turn bolts to the proximal end of the screed roller  12 . To facilitate this, the drive plate assembly  52  is equipped with a rearwardly extending hexagonal shaft  53  that is specifically designed to engage the internal surface of the drive socket  38 . Additionally, each of these components has an attachment pin hole  58 . The attachment pin holes  58  allow for the passage of an attachment pin or the like (not shown) through the drive socket  38  and hexagonal shaft  53  to secure the two together (such that they collectively rotate). 
     The drive plate assembly  52  also has a circular drive plate  44  that may be of the same outside diameter as the screed roller  12 . The drive plate  44  allows for the attachment of the drive plate assembly  52  to the screed roller  12  through the use of a plurality of bolts  54  or other suitable fasteners. Additionally, the distal surface of the drive plate  44  is equipped with a centrally located male shoulder  70  that operates to center a female attachment plug  46  of the screed roller  12  with reference to the drive plate assembly  52 . This configuration not only transfers the rotational power of the drive motor  24  to the screed roller  12 , but also ensures that all of the operational components are properly aligned. 
     The screed roller  12  is the elongated cylindrical component of the powered rotational screed apparatus  10  that performs the finishing or screeding operation, and may be defined by connecting one or more screed roller sections  12   a  in end-to-end relation. The external manner of construction of the screed roller  12  is illustrated in  FIGS. 5 and 6 . Each screed roller section  12   a  is made up of three primary components. The first of these is a tube body  50 , which is a tube of the desired inside and outside diameter and may be generally composed of a high strength aluminum alloy, although the use of other materials for this purpose is possible. Aluminum may be used in this application due to its desirable strength-to-weight ratio. The other components of an individual screed roller section  102   a  are a female and male attachment plug,  46  and  48 , respectively, disposed on the opposite ends of the tube body  50 . 
     The female and male attachment plugs,  46  and  48 , are relatively short cylindrical components having a shoulder of a common outside diameter of the tube body  50  and an engagement body that has an outside diameter that is equal to the inside diameter of the tube body  50 . Each screed roller section  12   a  is formed by fixedly attaching one female attachment plug  46  and one male attachment plug  48  to the opposite ends of the tube body  50 . This forms a complete unit that is then capable of being used individually or in conjunction with another screed roller section  12   a  as will be described in greater detail below. 
     The above-described method of constructing a screed roller section  12   a  provides a means by which the powered rotational screed apparatus  10  can be adapted to match the width of a wide variety of possible concrete pours. This is facilitated by the building of screed rollers  12  of varying lengths by joining together two or more individual screed roller sections  12   a  (again, another option is to use a single screed roller section  12   a  for the screed roller  12 ). This design allows for the construction of screed rollers  12  of varying lengths as illustrated by screed rollers,  60 ,  62 ,  64 , and  66 . Additionally, it must be stated that the lengths of the screed rollers as shown is intended to be for illustrative purposes only, and the construction of a screed roller of any usable length is possible. 
     The female and male attachment plugs,  46  and  48 , also contain a threaded hole  74  that passes longitudinally through their respective centers as illustrated in  FIG. 7 . The threaded hole allows  74  for the placement of a threaded rod  72  in a position so that it extends out beyond the outside end of the male attachment plug  48  to which it is fixedly attached. This attachment is accomplished by passing an attachment pin  56  through the body of the male attachment plug  48  in a manner so that it engages the threaded rod  72 . In this configuration, the attachment pin  56  is retained within the male attachment plug  48 , even when the screed roller  12  is disassembled. 
     The female attachment plug  46  is designed with a centrally located, with respect to its longitudinal axis, female recess  68  that extends into its body at the initial segment of its threaded hole  74 . Conversely, the male attachment plug  48  is designed with a similarly positioned male shoulder  70  that fits within the female recess  68  of the female attachment plug  46  of an adjacent screed roller section  12   a . Thus, the threaded rod  72 , the female recess  68 , and the male shoulder  70  components of the female and male attachment plugs,  46  and  48 , provide a means by which two or more screed roller sections  12   a  can easily and securely be connected to one another to define a screed roller  12 . Finally, once the proper connection has been accomplished through the described methods, the female attachment plug  46  can be locked in place with reference to the threaded rod  72 . This may be accomplished by the use of a securement bolt  76  that passes through the body of the female attachment plug  46  to engage the surface of the threaded rod  72 . The head of the securement bolt  76  may be accessible on an exterior of the screed roller  12 . 
     The connection of two or more screed roller sections  12   a  is then simply accomplished by connecting the desired screed roller sections  12   a  by the use of the threaded rod  72  and threaded hole  74  and their associated components. Also, this design provides a means of attaching additional components that will be discussed in greater detail below. 
     An attachment for the powered rotational screed apparatus  10  is illustrated in  FIGS. 8 and 9 , and is in the form of a wall plug or footing member  164 . The footing member  164  provides the powered rotational screed apparatus  10  with the capability of finishing a concrete slab that is used to form the floor of a basement where the footings  160  and walls  162  are already built. The footing member  164  is made up of a footing member body  165  that is attached to the non-powered end of the screed roller  12  using an outer bearing body  90 , a bearing  88 , and an inner bearing spacer  158 . 
     The footing member  164  is equipped with a ring spacer  166 . The ring spacer  166  is a circular plate that is inserted between the footing member body  165  and the footing member spacer  163  in a location so that it effectively raises the screed roller  12  up off of the footing  160 . Additionally, the footing member spacer  163 , the ring spacer  166 , and the footing member body  165  are held together by the use of a plurality of large bolts  124 . This design allows for the simplified pouring of such a concrete slab up to the wall and over the footing to properly construct a basement floor. 
     Another embodiment of a powered rotational screed apparatus or powered roller screed is illustrated in  FIG. 10  and is identified by reference numeral  10 ′. Corresponding components between the embodiments of  FIG. 1  and  FIG. 10  are identified by the same reference numeral. Those corresponding components between these two embodiments that differ in at least some respect and that are addressed herein are identified by a “single prime” designation in  FIG. 10 . Notwithstanding the existence of at least some differences between the embodiments, both powered roller screeds  10 ,  10 ′ screed in the same general manner—the screed roller  12  spins or rotates at a relatively high velocity (e.g., about 300 RPM), and is pulled by personnel in the opposite direction that the screed roller  12  is rotating. That is and for screeding operations, the screed roller  12  is pulled by personnel in the direction indicated by the arrow A as the screed roller  12  is rotating in the direction indicated by the arrow B. The direction that the screed roller  12  is rotating (arrow B) attempts to move the screed roller  12  in a direction that is opposite to the direction that the screed roller  12  is being pulled by personnel during screeding (arrow A). 
     Unless otherwise noted, all of the various features addressed above in relation to the powered roller screed  10  of  FIG. 1  may be utilized by the powered roller screed  10 ′ of  FIG. 10 . The powered roller screed  10 ′ of  FIG. 10  is illustrated as utilizing a drive motor  24 ′ (of the drive assembly  20 ′) that is in the form of an internal combustion engine, although any appropriate rotational power source may be utilized by the powered roller screed  10 ′ and including the electric motor illustrated in relation to the powered roller screed  10  of  FIG. 1 . The control handle  30  of the handle assembly  26  (used by an operator to pull on one end portion of the powered roller screed  10 ′) may also function as a hand-operated throttle for the drive motor  24 ′ to control the rotational speed of the screed roller  12 , while the other handle  32  of the handle assembly  26  may simply provide an appropriate gripping location for the operator&#39;s other hand. That is, and in also accordance with the powered roller screed  10  of  FIG. 1 , one operator may exert a pulling force on the screed roller  12  via the handle assembly  26  of the powered roller screed  10 ′ of  FIG. 10 , while another operator may exert a pulling force on the screed roller  12  via a pull device  22  (e.g., a rope, strap, chain, tether, tube-like structure or any other appropriate handle type/configuration). 
     The powered roller screed  10 ′ of  FIG. 10  is illustrated in a different type of concrete pour compared to the powered roller screed  10  of  FIG. 1 , and as such the powered roller screed  10 ′ of  FIG. 10  utilizes a different configuration (e.g., via incorporating two additional attachments). Instead of using a pair of forms  14  to screed as in  FIG. 1 , the powered roller screed  10 ′ in  FIG. 10  is being used to screed wet concrete  16  that has been poured between a pair of existing concrete slabs  14 ′ that have at least partially cured. That is, the concrete slabs  14 ′ have been allowed to cure at least to the degree where the concrete slabs  14 ′ will support personnel without adversely impacting the concrete slabs  14 ′ in any significant manner. In this regard, the powered roller screed  10 ′ includes a riser assembly  400  on a drive assembly end  21  of the screed roller  12 , along with a riser assembly  500  on a non-powered end  301  of the screed roller  12  member. Certain applications may require the use of only one of the riser assemblies  400 ,  500 . 
     Generally, the riser assemblies  400 ,  500  support the screed roller  12  on the pair of concrete slabs  14 ′, and furthermore maintain the spinning screed roller  12  in spaced relation to each of these concrete slabs  14 ′. That is, the screed roller  12  is allowed to spin or rotate relative to each of the riser assemblies  400 ,  500 . As such, the spinning screed roller  12  should not contact and mar the upper surface of either concrete slab  14 ′. Correspondingly, the lack of contact between the concrete slabs  14 ′ and the screed roller  12  should reduce wear and tear on the screed roller  12  as well for the illustrated screeding operation. Although the powered roller screed  10 ′ of  FIG. 10  is illustrated as using the same type of screed roller  12  used by the powered roller screed  10  of  FIG. 1 , the screed roller  12  used by the powered roller screed  10 ′ could be defined by a single screed roller section  12   a  of a fixed length (instead of a plurality of individual screed roller sections  12   a  joined in end-to-end relation, as described above). 
     Referring now to  FIGS. 10 and 11 , a drive assembly side  21  of the powered roller screed  10 ′ again includes a riser assembly  400  that can elevate the screed roller  12  a distance above a concrete slab  14 ′ during a screeding operation, and is freely rotatable relative to the screed roller  12 . In this regard and as illustrated in  FIG. 12 , a gap  402  can be created between a portion of the screed roller  12  and the concrete slab  14 ′. Moreover, as the drive assembly  20 ′ rotatably powers the screed roller  12 , the riser assembly  400  is free to rotate and contact the concrete slab  14 ′ as the operator(s) pull(s) on the handle assembly  26  and/or pull device  22  (e.g., the riser assembly  400  may roll along the concrete slab  14 ′ at a speed dictated by the axial or linear speed that the screed roller  12  is being pulled, for instance the speed that its rotational axis is being displaced). The screed roller  12  can therefore be prevented from contacting or otherwise engaging the concrete slab  14 ′, and can also level or finish the unfinished or poured concrete  16  at elevations above that of the concrete slab  14 ′. 
     An exploded view of the drive assembly end  21  of the powered roller screed  10 ′, along with the riser assembly  400 , is illustrated in  FIG. 13 . The output of the drive motor  24 ′ is configured so that it can be fitted to the drive socket  38 , which can be of a common 6-point impact type as illustrated in  FIG. 4  and discussed above. As the drive socket  38  passes through the motor frame  36 ′, it again is encased by a socket bearing (not shown in  FIGS. 12-13 ). The socket bearing again allows the drive socket  38  to spin with the drive motor  24 ′, while securely holding it within the stationary motor frame  36 ′. 
     Interconnecting the screed roller  12  and the drive assembly  20 ′ is a drive plate assembly  52 . The drive plate assembly  52  may include a drive plate  44  and a shaft  53  extending generally perpendicularly from the drive plate  44 . The drive plate  44  may have a circular shape or outer perimeter that is of the same outside diameter as the screed roller  12  and that allows for the attachment of the drive plate assembly  52  to the screed roller  12  through the use of a plurality of bolts or other suitable fasteners (not shown) being positioned through complementary shaped and sized apertures  45  in the drive plate  44  and apertures  69  in a female attachment plug  46 . Additionally, the distal surface of the drive plate  44  can be equipped with a centrally located male shoulder  71  that can be introduced into a female recess  68  on the female attachment plug  46  to center the female attachment plug  46  of the screed roller  12  with reference to the drive plate assembly  52 . This configuration not only transfers the rotational power of the drive motor  24 ′ to the screed roller  12 , but also ensures that all of the operational components are properly aligned. 
     The shaft  53  of the drive plate assembly  52  may have a hexagonal cross-section to engage the similarly shaped internal surface of the drive socket  38 . Additionally, each of the shaft  53  and the drive socket  38  may include at least one attachment pin hole  58  that allows for fixed securement of the drive plate assembly  52  to the drive socket  38  of the drive assembly  20 ′ (e.g., such that the shaft  53  will rotate along or collectively with the drive socket  38 ). In this regard, after the shaft  53  has been inserted into or otherwise engaged with the drive socket  38 , an attachment pin or other fastener can be passed through an attachment pin hole  58  on each of the shaft  53  and the drive socket  38  to secure the two components together. Once the drive plate  44  has been appropriately secured to the screed roller  12  and the shaft  53  has been appropriately secured to the drive assembly  20 ′, rotational power produced by the drive socket  38  can be directly transferred to the screed roller  12 . 
     The riser assembly  400  may be disposed over a portion of the shaft  53  between the drive plate  44  and the drive socket  38 . As will be described below, the riser assembly  400  includes a riser wheel  404  that elevates the screed roller  12  above the concrete slab  14 ′ and that allows a portion of the riser assembly  400  to rotate independently of the drive assembly  20 ′ and the screed roller  12 . As such, a portion of the riser assembly  400  is adapted to rotate at a speed that depends upon the linear or axial speed that the operator(s) advance the powered roller screed  10 ′. 
     The riser wheel  404  broadly includes an inner plug  406 , an inner ring  408 , and a bearing assembly  409 . The inner ring  408  may be in the form of a generally circular disc-shaped member having an axial bore  410  and a plurality of attachment apertures  412  disposed therethrough. The attachment apertures  412  allow washers  422  to be attached to the riser wheel  404  as will be later described. 
     The inner plug  406  of the riser wheel  404 , which can also be in the form of a generally disc-shaped member, includes a central aperture  414 , and can be press-fit or otherwise appropriately fixedly attached within the axial bore  410 . The central aperture  414  of the inner plug  406  is sized and shaped to accept the shaft  53  of the drive plate assembly  52  and to prevent the shaft  53  from rotating with respect to the inner plug  406  and the inner ring  408  (i.e., such that the inner plug  406  and shaft  53  will collectively rotate). For instance, the central aperture  414  may be hexagonally shaped to accept the hexagonally shaped shaft  53 . In other embodiments (not shown), the inner plug  406  may be removed and the axial bore  410  of the inner ring  408  may be formed to have a size and/or shape to non-rotatably accept the shaft  53  (i.e., such that the inner ring  408  and shaft  53  will collectively rotate). 
     The bearing assembly  409  includes an inner race  416 , an outer race  418 , a plurality of bearing members (not shown) situated between and within the inner and outer races  416 ,  418 , and a pair of seal members  420  (only one being shown, but with one being on each side of the bearing assembly  408 , where the two sides are spaced along the axis coinciding with the shaft  53 ) between the inner and outer races  416 ,  418 . The seal members  420  serve to protect the bearing members by reducing the potential for the introduction of debris into the interior of the bearing assembly  409 , and may be constructed of rubber, plastic, or any other suitable material. The inner and outer races  416 ,  418  can have complementary concave surfaces or other features that serve to contain the bearing members, and allow the bearing members to rotate or spin within the inner and outer races  416 ,  418 . The bearing members thus allow the inner race  416  to rotate freely relative to the outer race  418 , and as such may be in the form of balls, rollers, and the like. An outer portion of the inner ring  408  is appropriately secured to the inner race  416  by way of being press fit, the use of adhesives, or in any other appropriate manner. In this regard, the inner race  416  is fixedly and non-rotatably secured to both the inner ring  408  and the inner plug  406 . 
     The riser assembly  400  may further include a pair of washers  422 , each of which is secured to an outside or end surface of the riser wheel  404 . Each washer  422  can be a plastic, disc-shaped member with a central bore  424  and a plurality of attachment holes  426 . The attachment holes  426  are sized and spaced to substantially align with the attachment apertures  412  on the inner ring  408 . Thus, after assembly of the riser wheel  404 , the central bore  424  and attachment holes  426  of each washer  422  are respectively aligned over the central aperture  414  and attachment apertures  412  on one side of the riser wheel  404 . Thereafter, fasteners (e.g., bolts, not shown) can be inserted through the attachment holes  426  and the attachment apertures  412  to secure the respective washer  422  to the side of the riser wheel  404 . Each washer  422  serves to reduce the potential for the introduction of debris into the interior of the bearing assembly, in addition to reducing friction between the riser assembly  400  and the drive plate  44  and/or the drive assembly  20 . 
     An outer ring  428  may be fixedly secured around the riser wheel  404 . Outer ring  428  includes a central bore having a diameter that is equal to or just greater than an outer diameter of the riser wheel  404 . As will be later described, if the riser wheel  404  does not provide a desired gap  402  for a screeding operation, one or more outer rings  428  can be secured about the outer race  420  of the riser wheel  404  by way of one or more set screws or other fasteners, a press-fit, adhesives, or the like. The outer ring  428  is therefore non-rotatably secured relative to the outer race  418  (e.g., the outer ring  428  and outer race  418  will collectively rotate) and serves to increase an outer diameter of the riser wheel  404  relative to an outer diameter of the screed roller  12 . 
     There are a number of characterizations that may be made with regard to the riser wheel  404 . One is that the rotational axes of the riser wheel  404  and the screed roller  12  may be coaxial. Another is that the riser wheel  404  may be a free-spinning structure. The riser wheel  404  may rotate relative to the screed roller  12 . In one embodiment, the riser wheel  404  and the screed roller  12  rotate in opposite directions during a screeding operation (e.g., as the powered roller screed  10 ′ is being pulled in the direction indicated by arrow A in  FIG. 10 ). 
     With continued reference to  FIGS. 10-13 , one method of assembling the drive assembly end  21  of the powered roller screed  10 ′ will now be described. It will be appreciated that other assembly methods may be possible. Initially, the inner plug  406  is inserted into the axial bore  410  of the inner ring  408 , and the inner ring  408  is appropriately secured to or inserted within the inner race  416 . Thereafter, if the outer diameter of the riser wheel  404  is either less than that of the screed roller  12  or else is not of a desired magnitude, an outer ring  428  of appropriate size can be press-fit or otherwise appropriately secured (e.g., via one or more fasteners, such as one or more set screws) to the outer race  418  of the riser wheel  404 . Washers  422  can then be secured to the sides of the riser wheel  404  as described above. At this point, the riser assembly  400  has been assembled. 
     The drive plate  44  of the drive plate assembly  52  can be secured to the female attachment plug  46  of the screed roller  12 . More specifically, the centrally-located male shoulder  71  on the drive plate  44  can be aligned with and inserted into the female recess  68  in the accessible end of the female attachment plug  46 . Thereafter, bolts or other appropriate fasteners can be inserted through the complementary-shaped and sized apertures  45  on the drive plate  44  and apertures  69  on the female attachment plug  46  to fixedly secure the drive plate assembly  52  to the screed roller  12  (e.g., such that the drive plate assembly  52  and screed roller  12  may collectively rotate). 
     After the drive plate assembly  52  has been secured to the screed roller  12 , the shaft  53  may be inserted through the central aperture  414  of the inner plug  406  of the riser wheel  404 . As illustrated most clearly in  FIG. 13 , each of the shaft  53  and the central aperture  414  includes a hexagonal cross-section. Thus, once the shaft  53  has been inserted through the central aperture  414  and the riser assembly  400  is thus disposed on the shaft  53 , the drive plate assembly  52  and the screed roller  12  become non-rotatably attached relative to the inner plug  406 , inner ring  408  and inner race  416  (e.g., such that the shaft  53 , inner plug  406 , inner ring  408 , and inner race  416  may collectively rotate). Finally, the shaft  53  is inserted into the drive socket  38  such that at least one attachment hole  58  on the drive socket  38  is aligned with at least one attachment hole  58  on the shaft  53 . A fastener (e.g., bolt), pin, cotter key, or the like can then be inserted through the aligned attachment holes  58  to secure the drive plate assembly  52  and the screed roller  12  together such that each is inhibited from rotating or moving axially relative to the drive assembly  20 ′ (e.g., such that the output of the drive assembly  20 ′ may collectively rotate the drive plate assembly  52  and the screed roller  12 ). 
     At this point and as most clearly seen in  FIGS. 10-12 , the riser assembly  400  is situated on the shaft  53  between the drive socket  38  and the female attachment plug  46 , and the screed roller  12  is elevated a distance above the screeded concrete  18  equal to the gap  402 . While the shaft  53  is shown as being of a length that allows the riser assembly  400  to slide axially along the shaft  53  (while still being non-rotatable relative to the shaft  53 ) between the drive socket  38  and the female attachment plug  46 , in other embodiments the shaft  53  is of a length and/or the riser assembly  400  is of a width that allows the riser assembly  400  to slide only minimally or else not at all between the drive socket  38  and the female attachment plug  46 . 
     In operation, when the drive assembly  20 ′ causes the drive socket  38  to rotate, the: a) drive plate assembly  52 ; b) inner plug  406 , inner ring  408 , inner race  416  and washers  422  of the riser wheel  400 ; and c) screed roller  12  will correspondingly rotate at an identical frequency. As such, the screed roller  12  can be rotatably powered to perform a screeding operation of the poured concrete  16 . Conversely, the outer race  418  and any outer ring  428  of the riser assembly  400  (which is in contact with one of the concrete slabs  14 ′) generally will not rotate or otherwise spin unless an operator or other force moves the entire powered roller screed  10 ′ to a different location (e.g., during screeding). Even as the entire powered roller screed  10 ′ moves to a different location while the drive assembly  20 ′ is rotatably powering the screed roller  12 , the outer race  418  and any outer ring  428  of the riser assembly  400  will only rotate as fast as the entire powered roller screed  10 ′ moves between the locations. As such, screeding operations are facilitated for operators and the concrete slab  14 ′ will not be marred or scratched because the operators do not encounter resistance from friction between the screed roller  12  and the concrete slab  14 ′. Moreover, operators can more easily finish and level the freshly poured concrete  16  at elevations above those of the concrete slab  14 ′. 
     With reference now to FIGS.  10  and  14 - 17 , the non-powered end  301  of the powered roller screed  10 ′ is presented that broadly includes a portion of the screed roller  12 , the pull bearing assembly  84 , a wall plug  300 , and a riser assembly  500 . Like the riser assembly  400 , the riser assembly  500  can elevate the screed roller  12  a distance above the corresponding concrete slab  14 ′ during a screeding operation and a gap (not labeled) can be created between: a) a portion of the screed roller  12  and wall plug  300 ; and b) the corresponding concrete slab  14 ′ for reasons as previously described. 
     Partial exploded views of the non-powered end  301  of the roller screed  10 ′ are shown in  FIGS. 15 and 16 . The wall plug assembly  300  may be fixedly interconnected to the screed roller  12  and may sandwich the pull bearing assembly  84  along with the screed roller  12 . In this regard, the wall plug assembly  300  can serve to position the pull bearing assembly  84  away from a distal end portion of the screed roller  12  and thus facilitate screeding operations for operators. The wall plug assembly  300  may generally include a cylindrical member having an outer diameter the same as that of the screed roller  12  and that rotates with the screed roller  12 ; as such, the wall plug assembly  300  is non-rotatable relative to the screed roller  12  in the same manner as the above-noted wall plug  164 . 
     More specifically, the wall plug  300  may be in the form of a generally cylindrical extension member including first and second end walls  302 ,  304  and an outside or perimeter surface  306 . A cylindrical hub  308  extends from the first end wall  302  and is adapted to be received in a central aperture  89  of the pull bearing assembly  84  as will be later described. The cylindrical hub  308  includes an outer surface  309  having an outer diameter that is generally of the same magnitude as the diameter of the central aperture  89  of the pull bearing assembly  84 . In this regard and as will be later described, the cylindrical hub  308  can be disposed within the central aperture  89  of the pull bearing assembly  84  to fixedly and non-rotatably secure the wall plug  300  relative to an inner race  92  of the pull bearing assembly  84  (e.g., by providing a press-fit or interference fit between the wall plug  300  and the inner race  92  of the pull bearing assembly  84 ). 
     A female recess  310  may be situated within the cylindrical hub  308 . The female recess  310  is sized and shaped to accept the correspondingly sized and shaped male shoulder  70  on the male attachment plug  48  of the screed roller  12 . The female recess  310  and male shoulder  70  serve to center and align the wall plug  300  relative to the screed roller  12 . Located within the female recess  310  is a threaded bore  312  that is sized and shaped to accept the threaded rod  72  extending from the screed roller  12  (more specifically from a male plug  48  on an end of the screed roller  12 )). The wall plug  300  additionally includes a securement aperture  314  that intersects the threaded bore  312 . Securement aperture  314  is adapted to receive a securement bolt or the like (not shown) to engage the surface of the threaded rod  72  and secure the threaded rod  72  within the wall plug  300 . 
     With reference to  FIG. 16 , the second end wall  304  of the wall plug  300  may include a male shoulder  316  and a plurality of attachment apertures  318 . The male shoulder  316  is sized and shaped to engage with a female recess  528  on an end plug  504 , and the attachment apertures  318  are shaped to align with attachment bores  526  on the end plug  504  and accept fasteners as will be later described. 
     Referring back to  FIG. 15 , the pull bearing assembly  84  having first and second end surfaces  91 ,  93  is illustrated and is designed to provide an external surface on the screed roller  12  that is rotationally stationary when the bulk of the screed roller  12  and wall plug  300  are rotated during use. This is accomplished by the incorporation of an outer bearing body  90  that is rotationally isolated from the remaining components by a bearing assembly  88  (see  FIG. 9 ). The outer bearing body  90  is equipped with a pull ring  86  that allows for the attachment of an external rotationally stationary device to the screed roller  12 , such as pull device  22 . Outer bearing body  90  may be press-fit or otherwise appropriately secured about an outer portion of the bearing assembly  88  as will be later described. 
     Bearing assembly  88  surrounds a central aperture  89  and can include an inner race  92 , an outer race  94 , a plurality of bearing members (not shown) situated between and within the inner and outer races  92 ,  94 , and seal members  96  (only one being shown) between the inner and outer races  92 ,  94 . The inner and outer races  92 ,  94  can have complementary concave surfaces or other features that serve to contain the bearing members therebetween and that allow the bearing members to rotate or spin within the inner and outer races  92 ,  94 . The bearing members thus allow the inner race  92  to rotate freely relative to the outer race  94 , and as such may be in the form of balls, rollers, and the like. The outer bearing body  90  may be fixedly secured by way of a press-fit, for instance about the outer race  94 . In this regard and as seen back in  FIG. 10 , as an operator pulls on pull device  22 , the outer bearing body  90  and outer race  94  remain stationary while the inner race  92 , screed roller  12  and wall plug  300  can be rotated by the drive assembly  20 ′. 
     One method of connecting the screed roller  12 , pull bearing assembly  84 , and wall plug  300  will now be described, although other methods of connection are contemplated. Initially, the cylindrical hub  308  of the wall plug  300  is appropriately inserted or press-fit into the central aperture  89  from the first surface  91  to the second surface  93  of the pull bearing assembly  84  until the first surface  91  is in contact with the first end wall  302  of the wall plug  300  and the outer surface  309  of the cylindrical hub  308  has extended past the second surface  93 . In one embodiment, the outer surface  309  of the cylindrical hub  308  can extend past the second surface  93  by a distance of about ⅛″. 
     Thereafter, the male shoulder  70  on the male attachment plug  48  can be inserted into the female recess  310 , and the threaded rod  72  can be inserted into and threaded to the threaded aperture  312  until the threaded rod  72  at least extends to/past the securement aperture  314 . Finally, a securement bolt or the like can be threaded or otherwise inserted through the securement aperture  314  until it engages the threaded rod  72  to secure the threaded rod  72  within the wall plug  300 . At this point, the wall plug  300  is fixedly and non-rotatably secured relative to the inner race  92  of the pull bearing assembly  84  and the screed roller  12 , while the outer race  94  and the outer bearing body  90  are free to rotate independently of the wall plug  300 , inner race  92 , and screed roller  12 . Moreover, because the outer surface  309  of the cylindrical hub  308  was mounted to extend past the second surface  93 , in operation the pull bearing assembly  84  can slide axially along the cylindrical hub  308  by the distance that the cylindrical hub  308  extended past the second surface  93  during the connecting method. In this regard, the screed roller  12  and the wall plug  300  will not be prone to clamp or bind around the outer race  94  and outer bearing body  90  and thus inhibit their free rotation independent of the powered rotation of the screed roller  12 , inner race  92  and wall plug  300 . 
     The wall plug  300  positions the pull bearing assembly  84  and pull device  22  away from the end of the powered roller screed  10 ′. In this regard, an operator can screed freshly poured concrete right up to a wall or other vertical surface because the pull device  22  (and the operator&#39;s hands) are not directly adjacent to or abutting the wall or vertical surface. In an exemplary embodiment, the wall plug  300  can have a length of either 6 inches or 18 inches, but other wall plug  300  lengths are contemplated. 
     With continued reference to  FIG. 16 , the riser assembly  500  may broadly include a riser wheel  502  that serves to elevate a portion of the wall plug  300  and the screed roller  12  above a portion of the corresponding concrete slab  14 ′, and an end plug  504  that mounts the riser wheel  502  to a portion of the wall plug  300 . 
     The riser wheel  502  can have a central aperture  506 , a bearing assembly  508  surrounding the central aperture  506 , and an outer ring  510 , and may further be defined by first and second outer surfaces  505 ,  507 . Central aperture  506  is sized and shaped to accept connecting structures and fasteners associated with the wall plug  300  and the end plug  504  as will be later described. Similar to the bearing assembly  409 , the bearing assembly  508  can include an inner race  511 , an outer race  512 , a plurality of bearing members (not shown) situated between and within the inner and outer races  510 ,  512 , and a pair of seal members  514  (only one being shown) between the inner and outer races  510 ,  512 . The inner and outer races  510 ,  512  can have complementary concave surfaces or other features that serve to contain the bearing members therebetween and that allow the bearing members to rotate or spin within the inner and outer races  510 ,  512 . The bearing members thus allow the inner race  511  to rotate freely relative to the outer race  512 , and as such may be in the form of balls, rollers, and the like. 
     The outer ring  510  may be fixedly secured about the outer race  512  of the riser wheel  502  to provide a desired elevation of the wall plug  300  and screed roller  12  above the corresponding concrete slab  14 ′. Outer ring  510  includes a central bore having a diameter that is equal to or just greater than an outer diameter of the outer race  512 . As will be later described, one or more outer rings  510  can be fixedly secured about an outer portion of the outer race  512  to increase the diameter of the riser wheel  502  if the riser wheel  502  does not provide a desired elevation of the wall plug  300  and screed roller  12  above the concrete slab  14 ′ for a screeding operation. The outer ring  510  can be secured by way of one or more set screws or other fasteners, a press-fit, adhesives, and the like. 
     Continuing to refer to  FIG. 16 , the end plug  504  serves to secure the riser wheel  502  to the wall plug  300  and as such sandwiches the riser wheel  502  between the wall plug  300  and the end plug  504 . End plug  504  may include first and second discs  516 ,  518 . First disc  516  generally includes first and second outer surfaces  520 ,  522  and an outer diameter. The outer diameter generally matches that of the wall plug  300  and the screed roller  12 , and is generally larger than an outer diameter of the inner race  511  but smaller than an inner diameter of the outer race  512 . Second disc  518  is fixedly secured to the first disc  516 , and includes an outer surface  524  and an outer diameter smaller than that of the first disc  516 . More specifically, the outer diameter of the second disc  518  may be generally of the same magnitude as the diameter of the central aperture  506  of the riser wheel  502 . In this regard and as will be later described, the second disc  518  of the end plug  504  is adapted to be disposed within the central aperture  506  of the riser wheel  502  (e.g., to provide press-fit or interference fit between the end plug  504  and an interior portion of the riser wheel  502 ) to fixedly and non-rotatably secure the end plug  504  relative to the inner race  511 , the wall plug  300 , and the screed roller  12 . 
     The outer surface  524  of the second disc  518  can include a plurality of attachment bores  526  and a female recess  528 . Each attachment bore  526  extends from the outer surface  524  of the second disc  518  through the end plug  504  to the second outer surface  522  of the first disc  516  as shown in  FIG. 17 . As such, threaded fasteners (not shown) can be inserted through each attachment bore  516  from the second outer surface  522  of the first disc  516  and into the threaded attachment holes  318  on the wall plug  300  to fixedly and non-rotatably secure the end plug  504  relative to the wall plug  300 . Female recess  528  is sized and shaped to accept the correspondingly sized and shaped male shoulder  316  on the wall plug  300 . The female recess  528  and male shoulder  316  serve to center and align the end plug  504  relative to the wall plug  300 . Female recess  528  additionally includes a central bore  530  that is sized to accept the threaded rod  72  that fixedly connects the screed roller  12  and the wall plug  300 . 
     There are a number of characterizations that may be made with regard to the riser wheel  502 . One is that the rotational axes of the riser wheel  502  and the screed roller  12  may be coaxial. Another is that the riser wheel  502  may be a free-spinning structure. The riser wheel  502  may rotate relative to the screed roller  12 . In one embodiment, the riser wheel  502  and the screed roller  12  rotate in opposite directions during a screeding operation (e.g., as the powered roller screed  10 ′ is being pulled in the direction indicated by arrow A in  FIG. 10 ). 
     While one method of assembling the non-powered end  301  of the powered rotational screed apparatus  10  will now be described, other assembly methods may be possible. Initially, if the outer diameter of the riser wheel  502  is either less than that of the screed roller  12  and/or wall plug  300  or else is not of a desired magnitude, one or more outer rings  510  of appropriate size can be press-fit or otherwise appropriately secured to the outer race  512  of the riser wheel  502  (e.g., via one or more fasteners, such as one or more set screws). Thereafter, the second disc  518  of the end cap  504  can be appropriately inserted or press-fit into the central aperture  506  of the riser wheel  502  from the first outer surface  505  to the second outer surface  507  until the first outer surface  505  of the riser assembly  502  contacts the first outer surface  520  of the end plug  504  and the outer surface  524  of the second disc  518  has extended past the second outer surface  507  on the riser assembly  502 . In one embodiment, the outer surface  524  of the second disc  518  can extend past the second outer surface  507  by a distance of about ⅛″. 
     After the second disc  518  has been introduced into the central aperture  506 , the male shoulder may be positioned within the female recess  528  to align the wall plug  300  and end plug  504 . If necessary, either the wall plug  300  or end plug  504  can be rotated to align the attachment apertures  318  with the attachment bores  526 . Fasteners (not shown) can then be inserted from the second outer surface  522  of the first disc  516  of the end plug  504  into the attachment apertures  318  on the wall plug  300  to fixedly and non-rotatably secure end plug  504  relative to the wall plug  300 . Because the outer surface  524  of the second disc  518  was mounted to extend past the second outer surface  507  of the riser assembly  502 , in operation the riser assembly  502  can slide axially along the second disc  518  by the distance that the second disc  518  extended past the second outer surface  507  during the connecting method. In this regard, the wall plug  300  and the end plug  504  will not be prone to clamp or bind around the outer race  512  and outer ring  510  and thus inhibit their free rotation independent of the powered rotation of the wall plug  300 , inner race  511  and end plug  504 . 
     Although one way of integrating a riser wheel with each end of the screed roller  12  has been described herein, any appropriate way of doing so may be utilized. When a riser wheel is associated with each end of the screed roller  12 , the pair of riser wheels may have a common outer diameter or different outer diameters, depending upon the desired result. There also may be circumstances where only one of the riser wheels  404 ,  502  is utilized. 
     In operation and referring primarily to  FIG. 10 , rotational power generated by the drive assembly  20 ′ can be directly transferred to screed roller  12 , inner race  92  of pull bearing assembly  84 , wall plug  300 , inner race  511  of the riser wheel  502 , and end plug  504  to perform a screeding operation of the poured concrete  16 . Conversely, the outer race  94  and outer bearing body  90  of pull bearing assembly  84 , and the outer race  512  and any outer ring  510  of the riser assembly  500  (as well as the outer race  418  and any outer ring  428  being utilized by the riser assembly  400 ), can rotate or spin independently of the above-described components. For instance and as seen in both  FIGS. 10 and 14 , as an operator pulls on the roller screed  10 ′ using pull device  22 , the outer bearing body  90  of the pull bearing assembly  84  remains stationary. Moreover, the outer race  512  and any outer ring  510  of the riser wheel  502  (as well as the outer race  418  and any outer ring  428  being utilized by the riser assembly  400 ) only rotate as fast as the operator pulls the entire roller screed  10 . As such, screeding operations are facilitated for operators and concrete slabs  14 ′ will not be marred or scratched because the operators do not encounter resistance from friction between the a) screed roller  12 , wall plug  300  and/or end plug  504 , and b) the concrete slab  14 ′. Moreover, operators can more easily finish and level the poured concrete  16  at elevations above those of the concrete slabs  14 ′. 
     In summary and as shown in  FIGS. 10-12  and  14 , the riser assemblies  400 ,  500  can be utilized in conjunction with the powered roller screed  10 ′ to provide a gap  402  between the a) screed roller  12 , wall plug  300 , and end plug  504 , and the b) concrete slabs  14 ′. In other embodiments, only one of the drive assembly end  21  or non-powered end  301  includes a riser assembly  400 ,  500 . For instance, an operator may choose to utilize only one of the riser assemblies  400 ,  500  if only a single concrete slab  14 ′ exists or if the operator wishes to impart a slope or incline to the poured concrete  16  once it cures. In further embodiments, one or more of the riser assemblies  400 ,  500  may be associated with the powered roller screed  10 ′ at locations other than at the drive assembly end  21  or non-powered end  301 . Other applications for the use of a single riser assembly  400 ,  500  may also exist. 
     The outer rings  428  and  510  of the riser assemblies  400  and  500  can be constructed of various outer diameters. In some embodiments, the outer diameter of the outer rings  428  and  510  can be ¼″ greater than that of the screed roller  12  and wall plug  300 , which correspondingly elevates the screed roller  12  and wall plug  300  ⅛″ above the concrete slabs  14 ′. Such an elevation can facilitate a screeding operation for operators (e.g., contractors screeding a driveway) by decreasing the resistance experienced while pulling the powered roller screed  10 ′ in addition to reducing wear on the concrete slab  14 ′. In other embodiments, the outer diameter of the outer rings  428  and  510  can be ¾″ greater than that of the screed roller  12  and wall plug  300 , which correspondingly elevates the screed roller  12  and wall plug  300  ⅜″ above the concrete slabs  14 ′. Such an elevation is advantageous during the leveling of pervious poured concrete  16 . It should be appreciated that the outer rings  428 ,  510  can have outer diameters of other sizes such as 1¼″ and the like (to provide a ⅝″ gap). 
     Additionally, while male shoulders and female recesses have been shown in particular locations in the embodiments, the male shoulders and female recesses can be reversed without departing from the scope of the embodiments. Moreover, the various components of pull bearing assemblies, riser wheels, wall plugs and end plugs with the exception of the sealing members can be generally composed of a high strength aluminum alloy, although the use of other materials for this purpose is possible. Aluminum may be used in this application due to its desirable strength to weight ratio. 
     Although the embodiments of the powered roller screed  10 ′ have been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. 
     The foregoing description of embodiments of the present invention has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit the present invention to the forms disclosed herein. Consequently, variations and modifications commensurate with the above teachings, and skill and knowledge of the relevant art, are within the scope of the present invention. The embodiments described hereinabove are further intended to explain best modes known of practicing the present invention. The embodiments described hereinabove are further intended to enable others skilled in the art to utilize the present invention in such or other embodiments and with various modifications required by the particular application(s) or use(s). It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art.