Methods for the extrusion of novel, highly plastic and moldable hydraulically settable compositions

A method for extruding a hydraulically settable mixture to form an article of manufacture having a hydraulically settable matrix, the method including the steps of:

• mixing a hydraulically settable binder, at least one aggregate material, and water under sufficient shear to create a substantially homogeneous hydraulically settable mixture having an initial net deficiency of water such that the mixture is initially granular and substantially noncohesive;
• extruding the hydraulically settable mixture under a pressure sufficient to cause the mixture to become cohesive and flow through a die to form an article of manufacture of a desired shape and having a hydraulically settable matrix, the hydraulically settable matrix of the extruded article of manufacture being form-stable immediately after being extruded through the die, the hydraulically settable matrix including a wall having a thickness and defining a cavity, the wall thickness to cavity ratio of the hydraulically settable matrix being less than about 0.25;
• and
• allowing the hydraulically settable matrix of the extruded article of manufacture to cure.

A method for extruding a hydraulically settable mixture to form an article of manufacture having a hydraulically settable matrix, the method including the steps of:

• combining a hydraulically settable binder, at least one aggregate material, and water to form a hydraulically settable mixture having an initial net deficiency of water such that the mixture is initially granular and substantially noncohesive;
• extruding the hydraulically settable mixture under a pressure sufficient to cause the mixture to become cohesive and flow through a die to form an article of manufacture of a desired shape and having a hydraulically settable matrix, the hydraulically settable matrix of the extruded article of manufacture being form-stable immediately after being extruded through the die;
• and
• allowing the hydraulically settable matrix of the extruded article of manufacture to cure, wherein the cured hydraulically settable matrix of the article of manufacture has a bulk density less than about 1.5 g/cm.sup.3.

A method for extruding a hydraulically settable mixture to form an article of manufacture having a hydraulically settable matrix, the method including the steps of:

• mixing a hydraulically settable binder, at least one aggregate material, and water under sufficient shear to create a substantially homogeneous hydraulically settable mixture having an initial net deficiency of water such that the mixture is initially granular and substantially noncohesive;
• extruding the hydraulically settable mixture under a pressure sufficient to cause the mixture to become cohesive and flow through a die to form an article of manufacture of a desired shape and having a hydraulically settable matrix, the hydraulically settable matrix of the extruded article of manufacture being form-stable immediately after being extruded through the die;
• and
• allowing the hydraulically settable matrix of the extruded article of manufacture to cure, wherein the cured hydraulically settable matrix of the article of manufacture has a tensile strength greater than about 15 MPa.

A method for extruding a hydraulically settable mixture to form an article of manufacture having a hydraulically settable matrix, the method including the steps of:

• combining a hydraulically settable binder, at least one aggregate material, and water to form a hydraulically settable mixture having a water to hydraulically settable binder ratio less than about 0.35 w/w and having an initial net deficiency of water such that the mixture is initially granular and substantially noncohesive;
• extruding the hydraulically settable mixture under a pressure sufficient to cause the mixture to become cohesive and flow through a die to form an article of manufacture of a desired shape and having a hydraulically settable matrix, the hydraulically settable matrix of the extruded article of manufacture being form-stable immediately after being extruded through the die;
• and
• allowing the hydraulically settable matrix of the extruded article of manufacture to cure.

A method for extruding a hydraulically settable mixture to form an article of manufacture having a hydraulically wettable matrix, the method including the steps of:

• combining a hydraulically settable binder, at least one aggregate material, and water to form a hydraulically settable mixture, a portion of the water being available to interact with the hydraulically settable binder, the hydraulically settable binder and the portion of the water being available to interact with the hydraulically settable binder together forming a hydraulic paste having a water to hydraulically settable binder ratio less than about 0.27 w/w, the hydraulically settable mixture having an initial net deficiency of water such that the mixture is initially granular and substantially noncohesive;
• extruding the hydraulically settable mixture under a pressure sufficient to cause the mixture to become cohesive and flow through a die to form an article of manufacture of a desired shape and having a hydraulically settable matrix, the hydraulically settable matrix of the extruded article of manufacture being form-stable immediately after being extruded through the die;
• and
• allowing the hydraulically settable matrix of the extruded article of manufacture to cure.

A method for extruding a hydraulically settable mixture to form an article of manufacture having a hydraulically settable matrix, the method comprising the steps of:

• combining a hydraulically settable binder, at least one aggregate, and water to form a hydraulically settable mixture having an initial net deficiency of water such that the mixture is initially granular and substantially noncohesive, the hydraulically settable binder and aggregate material together including a plurality of particles having an initial particle packing density;
• extruding the hydraulically settable mixture under an extrusion pressure sufficient to increase the initial particle packing density, thereby decreasing the initial net deficiency of water of the hydraulically settable mixture such that the hydraulically settable mixture becomes substantially cohesive and is caused to flow through a die to form an article of manufacture of a desired shape and having a hydraulically settable matrix, the hydraulically settable matrix of the extruded article of manufacture being form-stable immediately after being extruded through the die;
• and
• allowing the hydraulically settable matrix of the extruded article of manufacture to cure.

A method for extruding a hydraulically settable mixture to form an article of manufacture having a hydraulically settable matrix, the method comprising the steps of:

• combining a hydraulically settable binder, at least one aggregate, a rheology-modifying agent and water to form a hydraulically settable mixture having an initial net deficiency of water such that the mixture is initially granular and substantially noncohesive, the hydraulically settable binder and aggregate together including a plurality of particles having an initial particle packing density;
• extruding the hydraulically settable mixture under an extrusion pressure sufficient to increase the initial particle packing density, thereby decreasing the initial net deficiency of water of the hydraulically settable mixture, the decrease in the initial net deficiency of water in combination with the rheology-modifying agent causing the hydraulically settable mixture to become substantially cohesive and to flow through a die to form an article of manufacture of a desired shape and having a hydraulically settable matrix, the hydraulically settable matrix of the extruded article of manufacture being form stable immediately after being extruded through the die;
• and
• allowing the hydraulically settable matrix of the extruded article of manufacture to cure.