A method is provided for producing a microfiber-reinforced high-strength concrete, comprising a cement matrix with a microfiber addition. The fiber elements have a shape-memory alloy. The method has at least the following steps: training a fiber shape of the fiber elements at a temperature above a transition temperature, wherein the fiber shape allows the fiber elements to latch; cooling the trained fiber elements; plastically deforming the fiber elements from the trained fiber shape into an intermediate form by means of which the fiber elements are prevented from latching; introducing the fiber elements into the cement matrix in order to form a fresh concrete; and casting the fresh concrete and heating the fresh concrete to the transition temperature such that the fiber elements reform into the fiber shape, thereby latching the fiber elements. The invention additionally relates to a microfiber-reinforced concrete which is produced using such a method.

There is described an online inspection method and system having an illumination system that provides bright-field and dark-field illumination concurrently or sequentially, at varying intensities, in order to acquire images that may be read by an image processing device. The image processing device may obtain measurements of features in the images and evaluate acceptability of the features.

A high toughness inorganic composite artificial stone panel and preparation method are disclosed. The panel includes a surface layer, an intermediate metal fiber toughening layer and a substrate toughening layer. The surface layer includes the following components: 40-70 parts of quartz sand, 10-30 parts of quartz powder, 20-45 parts of inorganic active powder, 0.5-4 parts of pigment, 0.3-1 part of water reducer and 3-10 parts of water. The intermediate metal fiber toughening layer includes the following components: 40-60 parts of inorganic active powder, 45-65 parts of sand, 0.8-1.5 parts of water reducer, 6-14 parts of water and 4-8 parts of metal fiber. The substrate toughening layer includes the following components: 30-50 parts of inorganic active powder, 30-55 parts of quartz sand, 15-20 parts of quartz powder, 0.5-1.2 parts of water reducer, 4-8 parts of water and 0.8-2.5 parts of toughening agent.

A concrete structure formed of a mixture of concrete and a plurality of custom manufactured twisted steel micro-rein-forcements (TSMRs). Each TSMR has a twist pitch of two or more twists per 25.4 mm applied along its longitudinal axis. The TSMRs are made from a common base stock and have the number of twists predetermined such that a concrete structure formed with at least 10 wt. % per unit volume less TSMRs than fibers in a conventional concrete structure exhibits the same or better performance than the conventional concrete structure in one or more of a stress, deflection, energy, or crack mouth opening (CMOD) properties as determined through defined standard tests. The performance requirement may be based on the actual test result and/or the consistency (coefficient of variation of the result).

A 4-dimensional printing system and method for printing reinforced concrete may allow reinforced concrete elements to be printed freeform and/or fully automated without the need for formwork, molding, or labor. The printing system may include software and hardware systems. The software system may process 3D models of the reinforced concrete element desired into multiple layers. The software system may utilize the individual layer to control operation of the hardware system to print the desired reinforced concrete element layer-by-layer. The hardware system may provide a concrete nozzle, a reinforcement material nozzle, as well as dispensing mechanisms for printing the materials at the desired locations and/or at desired times for the individual layer being printed. The hardware system may also include motion control mechanism(s) that allow the position of the nozzles to be moved sideward, up and down, and towards or away relative to the element being printed.

A concrete product set by pouring a concrete slurry includes a) a concrete mixture; b) a graphene oxide admixture; and c) at least one reinforcing fiber selected from the group of fibers. As the poured concrete slurry cures, the poured slurry hardens into a composite material product, and the composite material is embedded with graphene oxide. In another exemplary embodiment, the present invention is directed to a process for preparing a concrete product. The process comprises the steps of a) preparing a concrete slurry with integral graphene oxide; b) pouring the concrete slurry; c) allowing the concrete slurry to cure; and d) optionally spray-applying graphene oxide and/or optional colloidal silica as a curing technique. In another exemplary embodiment, the present invention is directed to the product itself; namely, a concrete product with fibers and embedded graphene oxide flakes.

A composite material structure can be constructed using an airforming process that includes filling the inflated support mold with a fluid structural material and allowing the fluid structural material to harden within the support mold. Additional steps can include inflating the support mold with a first fluid, forming fluid escape outlets in the support mold, and removing the support mold after allowing the fluid structural material to harden. The first fluid can be air, the support mold can be a fiberglass resin, and/or the fluid structural material can be a concrete composite material. Fluid can escape through the fluid escape outlets during the filling. The finished structure can include multiple structural components formed from a homogenous concrete composite material and having curved and non-planar geometries. The concrete composite material can include aluminum alloy fibers.

A fiber-reinforced prestressed reinforced concrete sleeper is integrally cast and includes a sleeper body and two rail bearing regions. A rail clamping base is arranged on a surface of the each rail bearing region. The two rail bearing regions are located under rails on both sides of the sleeper and the two rail bearing regions are located above the sleeper body. A reinforcing fiber is mixed into the two rail bearing regions only, and a reinforcing rib is arranged in the sleeper body. The reinforcing fiber is concentrated in a main stress region under the surface of the rail bearing regions. The reinforcing fiber arranged in a region with a large stress is more than the reinforcing fiber arranged in a region with a small stress.

A method is provided for producing a microfiber-reinforced high-strength concrete, comprising a cement matrix with a microfiber addition. The fiber elements have a shape-memory alloy. The method has at least the following steps: training a fiber shape of the fiber elements at a temperature above a transition temperature, wherein the fiber shape allows the fiber elements to latch; cooling the trained fiber elements; plastically deforming the fiber elements from the trained fiber shape into an intermediate form by means of which the fiber elements are prevented from latching; introducing the fiber elements into the cement matrix in order to form a fresh concrete; and casting the fresh concrete and heating the fresh concrete to the transition temperature such that the fiber elements reform into the fiber shape, thereby latching the fiber elements. The invention additionally relates to a microfiber-reinforced concrete which is produced using such a method.

A concrete structure formed of a mixture of concrete and a plurality of custom manufactured twisted steel micro-reinforcements (TSMRs). Each TSMR has a twist pitch of two or more twists per 25.4 mm applied along its longitudinal axis. The TSMRs are made from a common base stock and have the number of twists predetermined such that a concrete structure formed with at least 10 wt. % per unit volume less TSMRs than fibers in a conventional concrete structure exhibits the same or better performance than the conventional concrete structure in one or more of a stress, deflection, energy, or crack mouth opening (CMOD) properties as determined through defined standard tests. The performance requirement may be based on the actual test result and/or the consistency (coefficient of variation of the result).