Abstract:
The invention concerns a microgranular concrete composition based on slag cement, comprising 100 parts by weight (p) of slag cement; 15 p to 50 p of micro-elements with pozzolanic properties having a grain size between 0.1 and 1 νm, preferably between 0.1 and 0.5 νm; 10 p to 50 p of microelements with hydraulic properties having a D50 ranging between 2 and 10 νm, and a maximum grain size of 40 νm, preferably 30 νm; 90 p to 210 p of sand having a D50 ranging between 100 and 500 νm; and a maximum grain size not more than 1000 νm; 10 p to 40 p, preferably 20 p, of water; and 0.5 p to 5 p (dry extract) of a dispersing or fluidizing agent, the constituents other than water being slag in a proportion of 50 to 90 wt.% of said constituents. The composition can further contain metal fibres of different dimensions.
Abstract:
Articles are provided that are highly resistant to indentation, or impact, against their surfaces. The surfaces of these articles are functionally-graded in Young's modulus. Methods of making the article and methods of use of the article to resist impact are provided.
Abstract:
There are here disclosed carbon fibers for reinforcement of cement which are obtained by applying, onto the surfaces of carbon fibers, esters of oleic acid and aliphatic monovalent alcohols, esters of oleyl alcohol and monovalent fatty acids, polyoxyalkylene bisphenol ethers or polyether esters as sizing agents, and a cement composite material having a bending strength of 300 kgf/cm² or more which contains cut carbon fibers having a fiber length of 10 to 50 mm at a mixing volume ratio of the cut carbon fibers to the cement matrix in the range of 1 to 5%. According to the present invention, there are provided the carbon fibers for reinforcement of cement which have excellent adhesive properties to the cement, good process passage properties through a direct spray gun and good bundling properties and which are suitable for a direct spray method, and the cement composite material using the carbon fibers and having high bending strength.
Abstract translation:这里公开了用于增强水泥的碳纤维,其通过在碳纤维的表面上施加油酸和脂族一价醇的酯,油醇和一价脂肪酸的酯,聚氧化烯双酚醚或聚醚酯作为上浆剂而获得 以及弯曲强度为300kgf / cm 2以上的水泥复合材料,其含有纤维长度为10〜50mm的切割碳纤维,切割碳纤维与水泥基质的混合体积比为 范围为1〜5%。 根据本发明,提供了一种用于水泥加固的碳纤维,其对水泥具有优异的粘合性能,通过直接喷枪具有良好的工艺通道性能和良好的捆扎性能,并且适用于直接喷涂方法,并且 使用碳纤维的水泥复合材料并具有高弯曲强度。
Abstract:
A structural lightweight concrete with a high elastic modulus is described, consisting of a mixture of cement, water, hollow spherical lightweight aggregates, inert aggregates, preferably calcareous or silico-calcareous inert aggregates, wherein the weight ratio cement/hollow spherical lightweight aggregates, in the dry mixture, ranges from 0.6 to 0.9, preferably from 0.80 to 0.85 and wherein the water/cement weight ratio is equal to 0.44 and its use as structural lightweight concrete for the production of structural elements, preferably pillars, beams, walls, etc.
Abstract:
The invention relates to a green construction element forming a vertical surface of the construction, said element comprising: a) a porous concrete element and b) a coating on at least one of the surfaces of said porous concrete, directly in contact with said surface, said coating, which is favourable to the development of plants, comprising a plant or a seed of said plant, and the porous concrete having a porosity of between 10% and 40% in the hardened state thereof, before application of the coating, so as to be able to render said vertical surface of the construction green. The invention also relates to a method for producing such a green construction element.
Abstract:
A cement composition comprises white ordinary Portland cement having a particle size distribution characterized by a D95 of between 10 and 20 micrometres and metakaolin.
Abstract:
Methods of using the set-delayed cement slurries and compositions resulting from the combination of the set-delayed cement slurries are also described. A method may comprise providing a first set-delayed cement slurry comprising a pozzolanic cement and/or a Portland cement, water, and a first cement set retarder; providing a second set-delayed cement slurry comprising calcium-aluminate and a second cement set retarder; mixing the first slurry and the second slurry to form a cement composition; and allowing the cement composition to set.
Abstract:
A composite pavement structure comprises a wearing course layer and a base course layer disposed below the wearing course layer. The wearing course layer comprises aggregate, e.g. glass and rock, and an elastomeric composition. The elastomeric composition comprises the reaction product of an isocyanate component and an isocyanate-reactive component. The isocyanate component comprises a polymeric isocyanate, and optionally, an isocyanate-prepolymer. The isocyanate-reactive component comprises a hydrophobic polyol and a chain extender having at least two hydroxyl groups and a molecular weight of from about 62 to about 220. The chain extender is present in the isocyanate-reactive component in an amount of from about 1 to about 20 parts by weight based on 100 parts by weight of the isocyanate-reactive component. The base course layer comprises aggregate which is the same or different than the aggregate of the wearing course layer. Methods of forming the composite pavement structure are also disclosed.