A self propelled power trowel for finishing a concrete surface is equipped with reversible rotors to allow an operator to reverse the direction of rotation of rotor blades. The trowel includes a rigid frame adapted for operation over a concrete surface, a pair of rotor assemblies having rotor blades tiltably connected to the rigid frame for frictionally contacting the concrete surface and supporting the rigid frame thereabove, a prime mover mounted to the rigid frame and operatively coupled to drive the rotor blades of the rotor assemblies in opposite rotational directions. Synchronous or hydraulic motors are configured for causing, responsive to manual controls, reversal of the direction of rotation of the rotor blades.

A bridge paving machine and method for paving a 3D design without vertical profile rails includes converting a desired design into a 3D surface model to account for certain factors known to cause deviations in the paving processes and paving the 3D surface model in the expectation that factors will cause the 3D surface model to deflect into the desired design. An on-board computer system adjusts the 3D surface model in real-time to correct for on-site variables. The on-board computer system receives data from various external sensors, including deflection sensors fixed to girders in the bride structure, and paving machine-based sensors, and uses various predictive models to predict surface deflection based on the sensor data. The 3D surface model is continuously updated based on the predictive models and actual measured deflections.

A support structure for a float pan for floating a concrete surface provides an interface between the float pan and a rotating machine. The support structure is characterized by a hub configured for concentric attachment to a rotor, and by a plurality of trusses that extend radially from the hub, each providing a planar contact surface. A mounting plate attaches between each planar contact surface and a top surface of the float pan and is radially adjustable along the planar contact surface. A truss beam structure cross-links the trusses together. A. walk-behind or ride-on machine may incorporate the support structure and operate as a dedicated power flotation machine. Under weight of the machine, the planar contact surfaces of the trusses conform the float pan to a desired shape or radius of curvature for optimizing a flotation process.

A support structure for a float pan for floating a concrete surface provides an interface between the float pan and a rotating machine. The support structure is characterized by a hub configured for concentric attachment to a rotor, and by a plurality of trusses that extend radially from the hub, each providing a planar contact surface. A mounting plate attaches between each planar contact surface and a top surface of the float pan and is radially adjustable along the planar contact surface. A truss beam structure cross-links the trusses together. A. walk-behind or ride-on machine may incorporate the support structure and operate as a dedicated power flotation machine. Under weight of the machine, the planar contact surfaces of the trusses conform the float pan to a desired shape or radius of curvature for optimizing a flotation process.

An apparatus for screeding concrete to produce a level finished surface includes a frame assembly having a pair of spaced vertically oriented stabilization legs secured to the front end thereof supporting a generally horizontal front member. An extendable boom assembly is secured to said frame assembly at a first end and to a screed head at a second end. A side-step assembly includes an actuator with an extendable arm secured to said boom assembly to impart generally lateral motion.

An apparatus for screeding concrete to produce a level finished surface includes a frame assembly having a pair of spaced vertically oriented stabilization legs secured to the front end thereof supporting a generally horizontal front member. An extendable boom assembly is secured to said frame assembly at a first end and to a screed head at a second end. A side-step assembly includes an actuator with an extendable arm secured to said boom assembly to impart generally lateral motion.

An adjustable width mold apparatus for a slipform paver includes a center portion and left and right sideform assemblies. The center portion has left and right lateral ends. Left and right adjustable width support assemblies are connected between the sideform assemblies and the center portion. One or more spacers may be received between each sideform assembly and the center portion to adjust the width of the mold apparatus. The spacers may be hung on a plurality of hanger rods. Each of the hanger rods may have a hydraulic nut on one end thereof for clamping the spacers between the sideform assembly and the center portion.

The invention relates to a paver, in particular a slipform paver, having a machine frame 1 supported by front and rear undercarriages 2 and 3 and a paving device 6 for the paving of material. The invention relates additionally to a method of operating such a paver. The paver is provided with an apron monitoring device 13 configured to generate elevation profile data or elevation profile signals describing the elevation profile of the material deposited in the apron of the paving device 6 in a direction transverse to the working direction X. In addition, the paver has a data or signal processing device 16 receiving the elevation profile data or elevation profile signals. The apron monitoring device 13 provides the data needed to allow the material to be spread more evenly across the working width of the paver during the feeding operation by means of a spreading device for spreading the material to be paved in a direction transverse to the working direction X and/or to allow the spreading device to be controlled for improved spreading of the material after the paver has been fed.

A civil engineering machine has a machine control unit configured to determine data which defines the position and/or orientation of a reference point on the civil engineering machine in relation to a reference system independent of the position and orientation of the civil engineering machine. A geometrical shape to be produced on the ground is preset in either a machine control unit or a field rover control unit. The field rover is used to determine a position of at least one identifiable point of the preset geometrical shape in the independent reference system. Curve data defining a desired curve in the independent reference system, corresponding to the preset shape, is determined at least partially on the basis of the position of the at least one identifiable point of the preset geometrical shape in the independent reference system.

A civil engineering machine has a machine control unit configured to determine data which defines the position and/or orientation of a reference point on the civil engineering machine in relation to a reference system independent of the position and orientation of the civil engineering machine. A geometrical shape to be produced on the ground is preset in either a machine control unit or a field rover control unit. The field rover is used to determine a position of at least one identifiable point of the preset geometrical shape in the independent reference system. Curve data defining a desired curve in the independent reference system, corresponding to the preset shape, is determined at least partially on the basis of the position of the at least one identifiable point of the preset geometrical shape in the independent reference system.