A preparation method for a concrete additive for a maritime work environment includes: S1, compounding a volcanic ash material containing aluminum oxide and lime in proportion, loading a mixture into a sugar coating machine, and spraying a proper amount of alcohol, to prepare spherical particles; S2, adding the spherical particles in S1 and cement into the sugar coating machine, uniformly spraying deionized water in a rotating process, and coating surface layers of the spherical particles with a layer of cement for maintenance; and S3, placing the maintained particles in S2 into a hydrophobic emulsion, and coating the surface layers of the particles with a layer of hydrophobic emulsion, to obtain a concrete additive.

An anti-corrosive concrete grouting material for coastal structure connection and a method for preparing the same, belonging to the technical field of anti-corrosion of coastal assembled structure connectors. The grouting material includes the following components: expansible compound cement, slag sand, fly ash (FA), polyvinyl alcohol (PVA) (containing an oxidant and a catalyst), graphene oxide (GO), a water reducer, an adjusting admixture, a defoaming agent, a mineral admixture and water. A shrinkage-free effect of the grouting material is realized through internal curing of GO-PVA hydrogel, micro-expansion of the compound cement and shrinkage reduction effect of the FA; an energy storage effect of a GO-PVA hydrogel micro-capacitor is exerted to avoid formation of a reinforcement corrosion micro-battery in a grouting material sleeve, a reinforcement corrosion self-immune effect is achieved, seawater corrosion resistance of the grouting material is improved by the slag sand, and it has huge economic and environmental protection benefits.

A preparation method for a concrete additive for a maritime work environment includes: S1, compounding a volcanic ash material containing aluminum oxide and lime in proportion, loading a mixture into a sugar coating machine, and spraying a proper amount of alcohol, to prepare spherical particles; S2, adding the spherical particles in S1 and cement into the sugar coating machine, uniformly spraying deionized water in a rotating process, and coating surface layers of the spherical particles with a layer of cement for maintenance; and S3, placing the maintained particles in S2 into a hydrophobic emulsion, and coating the surface layers of the particles with a layer of hydrophobic emulsion, to obtain a concrete additive.

A cement composition is provided. The cement composition comprises: a microcapsule and cement. The microcapsule is provided with a core-shell structure having i) a core containing a water-repellent organosilicon material selected from the group consisting of organosilanes, organosilane partial condensation products, and branched siloxane resins, and ii) a shell of a silicon-based network polymer containing a silica unit. The microcapsule is included at 0.01 to less than 0.5 parts by weight per 100 parts by weight of the cement. Thus, it is possible to provide a cement composition that can provide a cured product having high strength, as well as excellent air content stability, substance penetration prevention, drying shrinkage, and freeze-thaw resistance.

A targeted corrosion inhibitor for marine reinforced concrete, and a preparation and application thereof. The targeted corrosion inhibitor is a nano silver-loaded nitrite-intercalated layered double hydroxide. The targeted corrosion inhibitor is prepared based on interlayer ion exchangeability of layered double hydroxides and specific recognition of Ag.sup.+ to chloride ions.

Concrete is formed by providing a wet layer of a first concrete 4, applying a second wet layer 6 of concrete on the first layer 4 of wet concrete and setting the layers 4 and 6 to provide a composite concrete structure, wherein at least one of the layers comprises, AACM (Alkali-Activated Cementitious Material). An ionic bond 2 is formed between the two layers. The AACM layer may comprise a reinforcement structure and cathodic protection.

A composition for forming a bio-compatible membrane applicable to building material, such as concrete, cement, etc., to a method of applying said composition for forming a biocompatible membrane, a biocompatible membrane, use of said membrane for various purposes, and to building material comprising said membrane.

Provided are a marine concrete composition using dechlorination microorganisms capable of easily removing chlorine generated by seawater through an electrical method by allowing electrons emitted from electricity-generating microorganisms to flow through steel fibers incorporated into ultra-high-performance concrete (UHPC) or high-performance fiber reinforced concrete (HPFRCC) through a dechlorination microbial capsule carrier and capable of self-healing concrete crack sites through a self-healing microbial capsule carrier and is also capable of fundamentally solving the problem of reduced durability against salt damage of ultra-high-performance concrete or high-performance fiber reinforced concrete for application in marine construction environments through a dechlorination microbial capsule carrier, and a method for constructing a marine concrete structure using the same.

A blended cementitious mixture is disclosed, the blended cementitious mixture comprising: a cement included in an amount corresponding to greater than 3% and less than 40% by mass of powders in the cementitious mixture; supplemental cementitious materials included in an amount corresponding to greater than 50% and less than 90% by mass of powders in the cementitious mixture and a carbonate source included in an amount less than or equal to 20% by mass of powders in the cementitious mixture. The cementitious mixture can be mixed with concrete sand, water, chemical admixtures and coarse aggregates and cured to form concrete.

Concrete is formed by providing a wet layer of a first concrete 4, applying a second wet layer 6 of concrete on the first layer 4 of wet concrete and setting the layers 4 and 6 to provide a composite concrete structure, wherein at least one of the layers comprises, AACM (Alkali-Activated Cementitious Material). An ionic bond 2 is formed between the two layers. The AACM layer may comprise a reinforcement structure and cathodic protection.