A self-propelled construction machine includes machine frame that is laterally extendible to adjust a width of the machine frame. A frame lock can selectively lock and unlock the machine frame to permit the width adjustment. A controller includes a frame extension mode configured to steer at least one ground engaging unit to provide a lateral force to adjust the width of the machine frame as the machine is driven across the ground surface by the ground engaging units.

A civil engineering machine and a method of controlling the machine are based on the position of at least one reference point which is relevant to the control of the civil engineering machine being changed, as the civil engineering machine moves, as a function of a relative position of the at least one reference point relative to a desired path of travel.

A compaction assembly can move in a direction of motion over particulate material. The compaction assembly can include a reciprocable agitating portion positioned along an axis perpendicular to the direction of motion. The agitating portion can move laterally along the axis and to agitate the material transverse to the direction of motion. The compaction assembly can further include a screed plate mounted behind the agitating portion with respect to the direction of motion, the screed plate configured to smooth the material.

An aggregate spreading system includes a dump truck that has a cab and a bed. The bed may contain an aggregate. A transport unit is coupled to the dump truck. The transport unit is positioned on the bed to urge the aggregate forwardly in the bed. A distribution unit is coupled to the dump truck. The distribution unit is positioned on the bed to receive the aggregate from the transport unit. Thus, the distribution unit distributes the aggregate onto a support surface. The distribution unit levels the aggregate on the support surface when the aggregate has been released onto the support surface.

A self-propelled construction machine includes a plurality of swing legs, each swing leg being supported from a ground surface by an associated crawler track steerably connected to an outer end of its associated swing leg. Pivotal movement of a swing leg may be accomplished by steering the associated crawler track through a non-zero steering angle until the lateral movement of the crawler track achieves the desired pivoting movement of the associated swing leg.

An excavator machine with a side mounted silt fence installing tool mounted below the swivel. The excavator has a swiveling and articulating tool and an operator's seat above the swivel. An articulating arm is attached above the swivel so the operator may operate swiveling and articulating tool in a coordinated way with the silt fence installer to accomplish a job more efficiently than it could be accomplished using tools separately mounted one at a time.

A system for varying the width of a molded concrete slab on the fly as the slab is being molded. Position and height of the paving machine relative to an external reference system are determined and controlled using at least two 3D stringless reference objects. An additional sensor provides a signal corresponding to a frame width and thus a concrete slab width, and an actuator controls the frame width actively as the paving machine advances.

In a self-propelled construction machine (1), in particular slipform paving machine, comprising a machine frame (2), at least three travelling devices (14), wherein the travelling devices (14) are each connected to the machine frame (2) by means of lifting columns (12), wherein at least two of the at least three travelling devices (14) are steerable by means of one each steering drive (6), wherein the respective steering drive (6) comprises at least one first part (10), which is connected to the respective travelling device (14), and one second part (16), which is connected to the respective lifting column (12),
it is provided that the steering drive (6) comprises at least one first toothed rack (22), wherein the first toothed rack is movable by means of at least one first linear drive means (26), wherein teeth of the at least one toothed rack engage with teeth of at least one toothed wheel (17), and the toothed wheel is thus rotatable by means of the movement of the toothed rack.