A process for making a layered multi-material structural element having controlled mechanical failure characteristics. The process includes the steps of: supplying a cementitious layer and forming a polymer layer on the cementitious layer by additive manufacture such that the polymer layer has a first thickness and the cementitious layer has a second thickness, wherein the polymer layer comprises a polymer and the cementitious layer comprises a cementitious material; and allowing the polymer from the polymer layer to suffuse into the cementitious layer for a period of time to obtain a suffused zone in the cementitious layer such that the suffused zone has a third thickness that is less than half the second thickness.

An additive of graphene nanomaterials for the improvement of cementitious compositions, a cementitious composition, a process for preparing a concrete a concrete and use of the concrete. The additive includes a mixture of graphene nanofibers, graphene oxide (GO), a dispersing agent (D) and a superplasticizer (SP), comprising at least two graphene nanofibers, selected among graphene nanofibers of high specific surface area (GNF-HS), graphene nanofibers of low specific surface area (GNF-LS) or graphene nanofibers of long length (GNF-LL), wherein the graphene nanofibers have an average diameter comprised between 2 nm and 200 nm, and wherein said additive of graphene nanomaterials by having different proportions of the at least two graphene nanofibers is fine-tuned for different cementitious compositions of particular properties.

An electrical grounding assembly includes an electrically conductive metal grounding substrate that is electrically connectable to a structure to be electrically grounded. A corrosion-protective jacket is on the grounding substrate. The jacket is electrically conductive and water impermeable, and includes a polymeric matrix and a particulate carbonaceous material dispersed in the polymeric matrix.

An electrical grounding assembly includes an electrically conductive metal grounding substrate that is electrically connectable to a structure to be electrically grounded. A corrosion-protective jacket is on the grounding substrate. The jacket is electrically conductive and water impermeable, and includes a polymeric matrix and a particulate carbonaceous material dispersed in the polymeric matrix.

The present invention belongs to the technical field of oil well cement preparation, and discloses a long-term high-temperature resistant and toughened well cementing and silica-cement composite material and a preparation method. A solid component comprises cement, alumina, superfine high-purity silica sand, a suspending agent and a toughening material according to weight fractions; the toughening material comprises a latex fiber toughening agent and a nano graphene sheet; and a liquid component is composed of water, nano iron oxide and an oil well cement admixture according to weight fractions. Cement slurry with a ratio of the present invention can achieve compressive strength reaching up to 31 MPa after being cured under a high-temperature and high-pressure environment of 200° C. and 150 MPa for one year; and the gas permeability is controlled below 0.02 mD.

The present invention belongs to the technical field of oil well cement preparation, and discloses a long-term high-temperature resistant and toughened well cementing and silica-cement composite material and a preparation method. A solid component comprises cement, alumina, superfine high-purity silica sand, a suspending agent and a toughening material according to weight fractions; the toughening material comprises a latex fiber toughening agent and a nano graphene sheet; and a liquid component is composed of water, nano iron oxide and an oil well cement admixture according to weight fractions. Cement slurry with a ratio of the present invention can achieve compressive strength reaching up to 31 MPa after being cured under a high-temperature and high-pressure environment of 200° C. and 150 MPa for one year; and the gas permeability is controlled below 0.02 mD.

Cured cements, cement slurries, and methods of making cured cement and methods of using cement slurries are provided. The method of making a modified cement slurry includes adding particles comprising carbon nanotube sponges disposed on sacrificial templates to a cement slurry to form the modified cement slurry and allowing the sacrificial templates to disintegrate, thereby leaving the carbon nanotube sponges dispersed throughout the modified cement slurry.

Cured cements, cement slurries, and methods of making cured cement and methods of using cement slurries are provided. The method of making a modified cement slurry includes adding particles comprising carbon nanotube sponges disposed on sacrificial templates to a cement slurry to form the modified cement slurry and allowing the sacrificial templates to disintegrate, thereby leaving the carbon nanotube sponges dispersed throughout the modified cement slurry.

Methods of determining the integrity of a well are provided. The methods include mixing conductive materials into a fluid, introducing the fluid into the well, and allowing the conductive materials to coat a surface of a subsurface formation, thereby forming an electrically conductive data conduit coating. The methods further include transmitting data through the electrically conductive data conduit coating to determine the integrity of the well.

Methods of determining the integrity of a well are provided. The methods include mixing conductive materials into a fluid, introducing the fluid into the well, and allowing the conductive materials to coat a surface of a subsurface formation, thereby forming an electrically conductive data conduit coating. The methods further include transmitting data through the electrically conductive data conduit coating to determine the integrity of the well.