A power unit is configured for use as part of a concrete screed and includes a frame and a powered drive. The frame includes a drive housing. The powered drive is operably supported by the drive housing and is configured to rotate a rotatable concrete forming drum. The powered drive includes an electric motor and a battery operably coupled to the electric motor and configured to power the electric motor. The powered drive includes a drive shaft drivingly connectable relative to the drum, with rotation of the drive shaft causing corresponding rotation of the drum.

Methods, systems, and devices, are developed for in-situ placement of a concrete mix that can have the thixotropy to hold vertical dimension without containment, while maintaining pliability to be pumped into place and manipulated to a desired shape, and can be combined with concrete set accelerators, allowing subsequent layers of this concrete mix to be continuously stacked in place to build tall walls and such without the use of forms. Concrete without these special properties is pumped toward the point of placement where it is modified by injecting and mixing, into that line of pumped concrete, an admixture containing thixotropes, thickeners and/or set accelerators or other modifiers to provide these properties and other improvements. This method allows conventional plant batching with commonly available constituent materials for batching an economical concrete that is delivered to a jobsite and then is pumped most of the way to a point of placement.

Methods, systems, and devices, are developed for in-situ placement of a concrete mix that can have the thixotropy to hold vertical dimension without containment, while maintaining pliability to be pumped into place and manipulated to a desired shape, and can be combined with concrete set accelerators, allowing subsequent layers of this concrete mix to be continuously stacked in place to build tall walls and such without the use of forms. Concrete without these special properties is pumped toward the point of placement where it is modified by injecting and mixing, into that line of pumped concrete, an admixture containing thixotropes, thickeners and/or set accelerators or other modifiers to provide these properties and other improvements. This method allows conventional plant batching with commonly available constituent materials for batching an economical concrete that is delivered to a jobsite and then is pumped most of the way to a point of placement.

An apparatus for screeding concrete to produce a level finished surface includes a frame assembly having a front end and rear ends and a pair of spaced vertically oriented stabilization legs supporting a generally horizontal front member. An extendable boom assembly is provided having front and rear ends, and an exterior boom section pivotably secured to the frame assembly proximate said rear end. The extendable boom assembly is also adjustably mounted on said front member to allow generally lateral motion of the boom.

Methods and systems for making and using a wide swath offset concrete screed apparatus for screeding wet concrete slurry. The apparatus includes a cross support bar, an attachment mechanism for attaching the cross support bar to a liftable arm of a motorized vehicle, and lateral support bars for attaching a screed bar to the cross support bar. The screed bar is positioned offset from the motorized vehicle used to operate the screed, allowing the motorized vehicle to drive outside the forms.

Methods and systems for making and using a wide swath offset concrete screed apparatus for screeding wet concrete slurry. The apparatus includes a cross support bar, an attachment mechanism for attaching the cross support bar to a liftable arm of a motorized vehicle, and lateral support bars for attaching a screed bar to the cross support bar. The screed bar is positioned offset from the motorized vehicle used to operate the screed, allowing the motorized vehicle to drive outside the forms.

An apparatus for leveling a concrete screed having a frame and a screed head secured thereto includes a plurality of vertically adjustable leveling legs driven by a plurality of electrical actuators responsive to a command supplied by a user interface.

An apparatus for leveling a concrete screed having a frame and a screed head secured thereto includes a plurality of vertically adjustable leveling legs driven by a plurality of electrical actuators responsive to a command supplied by a user interface.

An apparatus for steering and driving a concrete screed having a frame and a screed head secured thereto includes a plurality of spaced drive wheels rotatably and pivotably secured to the frame at a plurality of points, and a steering member coupled to one or more of the drive wheels for controlling the directional orientation thereof.

An apparatus for steering and driving a concrete screed having a frame and a screed head secured thereto includes a plurality of spaced drive wheels rotatably and pivotably secured to the frame at a plurality of points, and a steering member coupled to one or more of the drive wheels for controlling the directional orientation thereof.