Self-stressing engineered composite materials, methods of self-stressing engineered composite materials, and self-stressing reinforcement for same

An engineered composite, comprising:

• a matrix;
• self-stressing reinforcement contained in the matrix, wherein the self-stressing reinforcement is designed, configured, and comprised of a material composed to respond chemically to an activator so as to cause the self-stressing reinforcement to undergo a change in internal stress within the self-stressing reinforcement and thereby impart compressive stress into adjacent portions of the matrix in physical contact with the self-stressing reinforcement;
• and
• the activator, wherein the activator is selected in conjunction with the material of the self-stressing reinforcement to activate the self-stressing reinforcement and is selected from the group consisting of:
• a self-activator present within the matrix but not as an additive;
• and
• an internal activator within the matrix and added to the matrix as an additive;
• wherein:
• the self-stressing reinforcement comprises, within the matrix, a releasing component and an active component;
• the releasing component is chemically activated by the activator to release pre-stress in the active component so as to transfer a portion of the pre-stress into the adjacent portions of the matrix to create the compressive stress in the adjacent portions of the matrix;
• and
• the active component comprises a core and the releasing component comprises a sleeve surrounding the core and holding the core in tension prior to activation, wherein the sleeve comprises the at least one material that responds chemically to the activator.

An engineered composite, comprising:

• a matrix;
• self-stressing reinforcement contained in the matrix, wherein the self-stressing reinforcement is designed, configured, and comprised of a material composed to respond chemically to an activator so as to cause the self-stressing reinforcement to undergo a change in internal stress within the self-stressing reinforcement and thereby impart compressive stress into adjacent portions of the matrix in physical contact with the self-stressing reinforcement;
• and
• the activator, wherein the activator is selected in conjunction with the material of the self-stressing reinforcement to activate the self-stressing reinforcement and is selected from the group consisting of:
• a self-activator present within the matrix but not as an additive;
• and
• an internal activator within the matrix and added to the matrix as an additive;
• wherein:
• the material comprises a poly-base polymer responsive to the activator;
• and
• the poly-base polymer comprises a pH-responsive material selected from the group consisting of chitosan-derived biopolymers and collagens.

An engineered composite, comprising:

• a matrix;
• self-stressing reinforcement contained in the matrix, wherein the self-stressing reinforcement is designed, configured, and comprised of a material composed to respond chemically to an activator so as to cause the self-stressing reinforcement to undergo a change in internal stress within the self-stressing reinforcement and thereby impart compressive stress into adjacent portions of the matrix in physical contact with the self-stressing reinforcement;
• and
• the activator, wherein the activator is selected in conjunction with the material of the self-stressing reinforcement to activate the self-stressing reinforcement and is selected from the group consisting of:
• a self-activator present within the matrix but not as an additive;
• and
• an internal activator within the matrix and added to the matrix as an additive;
• further comprising first and second layers of matrix material forming an interface with one another, wherein the self-stressing reinforcement extends across the interface so as to inhibit delamination between the first and second layers at the interface.