The invention discloses an alkali slag foamed concrete sound absorption material and a preparation method thereof. The sound absorption material comprises granulated blast furnace slag, an alkali activator, a foaming agent, a catalyst, a foam stabilizer and a crack arresting agent, wherein the component of an alkali slag gel is blast furnace slag, the alkali activator is one kind or two kinds of combinations of water and sodium hydroxide, the foaming agent is hydrogen peroxide, the catalyst is potassium permanganate, the foam stabilizer is calcium stearate, and the crack arresting agent is one kind or two kinds of combinations of polypropylene fiber and polyvinyl alcohol fiber; in addition, water with a certain weight percentage is added in producing. According to the method, the obtained alkali slag foamed concrete sound absorption material has the advantages of green environmental protection, low cost, and high durability. The preparation method has the advantages of low energy consumption and environmental friendliness.

Alkali slag foamed concrete sound absorption material and preparation method thereof

The invention relates to ultra-high-performance steel fiber reinforced concrete, which is prepared from cement, silica fume, standard sand or river sand, a water reducing agent, water and copper-coated steel fibers. A preparation method of the ultra-high-performance steel fiber reinforced concrete comprises the steps of adding the cement, the standard sand or river sand, the silica fume and a component B of the water reducing agent into a forced mixer, and evenly mixing to prepare a dry material; adding half of a component A of the water reducing agent and the water into the dry material, and evenly mixing; adding the rest half of the component A of the water reducing agent and the water into the dry material, and evenly stirring; adding the steel fibers for 3-5 times, and continuously stirring until the steel fibers are evenly distributed. Tests prove that test pieces prepared from the ultra-high-performance steel fiber reinforced concrete have the compressive strength exceeding 150MPa and the ultimate tensile strength exceeding 6MPa, have good flowability and are easy to maintain. The ultra-high-performance steel fiber reinforced concrete is suitable for lower structures of reinforced concrete bridges, steel-concrete composite structure bridges and the like as well as lower structures of piers and abutments of the bridges.

Ultra-high-performance steel fiber reinforced concrete and preparation method thereof

The invention belongs to the technical field of concrete additives and relates to a high freezing resistance water permeable concrete additive and a preparation method thereof The high freezing resistance water permeable concrete additive consists of the following components in parts by weight: 5-10 parts of mixing materials, 05-10 parts of a water reduction agent, 01-1 part of a thickening agent and 3-6 parts of a water repellent agent, wherein the mixing material is silicon ash or coal ash; and the granularity of the mixing material is 300-400 meshes The preparation method comprises thefollowing steps: mixing the mixing material, the water reduction agent, the thickening agent and the water repellent agent according to the parts by weight, grinding, stirring the mixed material at amedium speed till the components are uniform, and discharging The additive provided by the invention is capable of enriching fine capillary cavities and micro cracks in a cementing layer of water permeable concrete, improving the strength of a cement adhesive layer, and improving the strength of the water permeable concrete, so that the freezing resistance of the concrete is improved In addition, due to adoption of the water repellant agent, a water repellant surface is formed on the surface of the cementing layer of concrete, so that water inside the concrete can be well discharged, and thefreezing resistance and the water permeability of the concrete are improved

High freezing resistance water permeable concrete additive and preparation method thereof

The invention discloses a previous concrete improving agent. The previous concrete improving agent comprises the following raw materials in parts by weight: 80-90 parts of cement, 6-10 parts of mineral powder, 6-10 parts of silica fume and 1-3 parts of an additive, wherein the additive is a mixture of polyacrylamide, a polycarboxylate superplasticizer, a retarder, a thickening agent and redispersible gelatine powder. Meanwhile, the invention provides a preparation method of the previous concrete improving agent. The preparation method comprises the following steps: weighing the cement, the mineral powder, the silica fume and the additive in parts by weight; and mixing and uniformly stirring to obtain the improving agent. The previous concrete improving agent has the beneficial effects thatthe integral strength of previous concrete is improved, durability of the previous concrete is enhanced, and workability of the previous concrete is improved.

Previous concrete improving agent and preparation method thereof

The invention discloses a sound-absorption and noise-reduction tunnel segment and a prefabrication method thereof. The segment is of a tile-shapedstructure. The segment comprises a structure layer consisting of reinforced concrete; a sound-absorption layer taking foam concrete as a sound-absorption material is arranged on the inner arc surface of the structure layer; the sound-absorption layer andthe structure layer are prefabricated into an integral structure through a same prefabrication mold; preferably, the sound-absorption layer is internally provided with a steel wire mesh framework andthe structure layer is internally provided with a rebar cage; and outwardly-extended steel wires at the edge of the steel wire mesh are bent and anchored in the structure layer. The prefabrication method comprises the steps of forming the sound-absorption layer in a segment mold by spraying the foam concrete, and then forming the reinforced concrete structure layer on the sound-absorption layer which is not completely solidified. The sound-absorption and noise-reduction tunnel segment has the beneficial effects of great sound absorption and noise reduction properties, high strength, high impermeability,the simple structure, good interlayer bonding performance and long service life. The prefabrication method has the beneficial effects of simplicity, convenient operation, sequential formingof the two layers, green environmental protection and noincrease in the on-site construction workload, and is especially suitable for multi-mold assembly line operations.

Sound-absorption and noise-reduction tunnel segment and prefabrication method thereof

The invention discloses a specialadmixture for pervious concrete and application of the specialadmixture. Thespecial admixture comprises the following materials in weight percent: 5 to 15 percent (solid content) of a water reducing agent; 0.1 to 1 percent of a retarder; 0.1 to 1 percent of a thickener; 15 to 25 percent of an early strength agent; 25 to 50 percent of a water-repellent agent; 25 to 50 percent of rubber powder. The admixture overcomes the problem that the existing pervious concrete is not easy to transport bya tanker, and ensures that the phenomenon of blocking cannot occur when the pervious concrete is put into a tanker after the admixture is used, has excellent service behavior after the pervious concrete is discharged from the tanker, and has excellent cohesiveness, without phenomena of bottom sealing and hole blocking.

Specialadmixture for pervious concrete and application ofspecialadmixture

The utility model discloses a pin -connected panel high -speed railway sound barrier acoustic baffle, constitute by aerated concrete perforated plate, resonating cativty, foam concrete abatvoix, active powder concrete floor. The bottom plate is active powder precast concrete's the U type trough plate of both wings from top to bottom that has, and both wings embed the zigzag draw -in groove for fixed foam concrete abatvoix and aerated concrete perforated plate. This patent has adopted cast -in -place foam concrete as sound absorbing material, there is the cockscomb structure draw -in groove bottom plate both wings inboard, the cohesiveness that can effectually increase sound absorbing material with the bottom plate, increase the weatherability and the durability of whole abatvoix, cast -in -place foam concrete material carries out surface profile with the wave instrument when final set in addition, make the resonating cativty that forms by foam concrete and aerated concrete perforated plate present cavity width variation, the frequency of inhaling the sound has been increased, it strengthens to make this acoustic baffle effectively absorb sound the frequency.

Pin -connected panel high -speed railway sound barrier acoustic baffle

The invention discloses steel fiber concrete with high fracture resistance and a preparation method thereof. The steel fiber concrete comprises matrix concrete and steel fiber, and is characterized in that: the volume percent content of the steel fiber is 3.5%; and the used raw materials comprise the following materials by weight: 125-175Kg of water, 500-542Kg of cement, 25-38Kg of silica fume, 40-60Kg of fly ash, 500-662Kg of sand, 800-953Kg of stone, 10-16Kg of a pumping agent, and 250-273Kg of steel fiber. During stirring of concrete production, the steel fiber in the steel fiber concrete disclosed by the invention cannot agglomerate easily, so that the steel fiber concrete has good construction workability and can meet pouring construction requirements; the breaking strength of the concrete is greatly improved, high-performance concrete with the breaking strength of 20MPa is successfully prepared, and under an equal strength condition, the thickness of a concrete pavement is reduced, and the construction cost is reduced. This special type of concrete can be applied to construction parts with high requirements on crack control, toughening and shock resistance, and can be widely applied to road, bridge and pavement constructions.

Steel fiber concrete with high fracture resistance and preparation method thereof

The invention discloses a special admixture for full-lightweight ceramsite concrete and a preparation method. The special admixture is characterized by being prepared from the following composition materials in percentage by weight: (A) an air-entraining ingredient, (B) thickening and water retention ingredients, (C) a bubble stabilizing ingredient and (D) deionized water. The admixture is independent of water reducing type admixtures (pumping aids) on the market and is used in a manner of being combined with the water reducing type admixtures. Through adding small and stable bubbles, the size distribution of mortar is optimized, and the placeability of the full-lightweight ceramsite concrete can be greatly improved through the microbead effect of spherical and uniform small bubbles. By adding the admixture, the volume weight of the mortar in the full-lightweight ceramsite concrete is lowered, so that the difference between the volume weight of ceramsite and the volume weight of the mortar is reduced, and the rate of floating of the ceramsite is lowered; and the thickening and bubble stabilizing ingredients are further added into the admixture, on one hand, the viscosity of a system is improved by the thickening ingredient so as to inhibit the floating of the ceramsite, on the other hand, by adding the thickening ingredient, the bubbles can more stably exist in the ceramsite concrete.

Special admixture for full-lightweight ceramsite concrete and preparation method

The invention discloses a rapid repair mortar and a repair process for an autoclaved aerated concrete slab. The repair mortar takes gypsum mortar as a substrate material doped with a functional admixture, and is characterized by comprising the following components in parts by weight: 90-100 parts of gypsum mortar, 0.5-1.5 parts of an additive, and 25-30 parts of a retarder aqueous solution. The repair process comprises the following steps: cleaning a damaged surface, mixing the repair mortar, smearing a small amount of the mortar on the damaged surface and squeezing and compacting the mortar at first, then filling a damaged part compactly with a large amount of the mortar, trimming and flattening the mortar after final set of the mortar, and finally, performing polishing. The repair technology has the characteristics of convenience in operation, high repair speed, basically no chromatic aberration, and firm agglutination between the repair mortar and an autoclaved aerated concrete base, and the like, so that the repair efficiency can be greatly improved, and the damage rate is reduced.

Wu Xin

Papers

Specialadmixture for pervious concrete and application ofspecialadmixture

Pin -connected panel high -speed railway sound barrier acoustic baffle

Steel fiber concrete with high fracture resistance and preparation method thereof

Special admixture for full-lightweight ceramsite concrete and preparation method

Rapid repair mortar and repair process special for autoclaved aerated concrete slab