44results about How to "Does not affect durability" patented technology

The present invention has: an inner cylinder (11), which is connected to one of the vibration generating part and the vibration receiving part; an outer cylinder (12), which is connected to the other side of the vibration generating part and the vibration receiving part; an intermediate cylinder (13) , which is pressed into the inner peripheral surface of the outer cylinder (12); the main body elastic body (14), which connects the inner cylinder (11) and the middle cylinder (13); and the stop elastic body (15, 16), which is relatively The main body elastic body (14) is independent, and the stopper elastic body (15, 16) is fixed on the middle cylinder (13) and faces inward at least across the cavity part (17, 18) in the direction perpendicular to the axial direction of the inner cylinder In the cylinder (11), the cavity parts (17, 18) are formed so as to pass through the main body elastic body (14) in the axial direction of the inner cylinder. The stopper elastic bodies (15, 16) respectively have axial stoppers (15a, 16a), and the axial stoppers (15a, 16a) protrude axially from the inner cylinder to the middle cylinder (13) and the outer cylinder (12 ) outside.

The invention relates to the technical field of tunneling engineering, in particular to a fixing device for the surface of a tunnel shield segment, comprising: a fastener in a fixing hole of a shield segment, a hook-shaped connecting rod, and a fastening installation piece on the surface of a segment The fasteners in the fixing hole of the shield segment include a top hole fixer, a nut sleeve, and a connecting rod, and the connecting rod adopts a threaded structure, which is matched with the top hole fixer and the nut sleeve 2 threads; The hook-shaped connecting rod adopts a hook shape on one side and a threaded rod shape on one side, and is used to connect the internal fasteners in the fixing holes of the shield segment and the fastening installation parts on the surface of the segment; the surface of the segment is fastened Mounting parts include surface mounting plate and support feet with slope. The invention utilizes the inherent structure in the segment fixing hole to fix the equipment without additional drilling and prevents damage to the segment structure; the installation and construction do not generate smoke and noise, and the installation position is relatively flexible and easy to disassemble.

The invention discloses a later-period obviously-enhanced cement grinding aid and a preparation method thereof, belonging to the field of cement preparation. The grinding aid comprises the following components in percentage by mass: 10-40% of alkylol amine composition, 5-10% of anhydrous sodium sulfate, 1-3% of acetic acid, 10-30% of sodium gluconate, 5-20% of glycerol, 5-20% of molasses and the balance of water. The preparation method comprises the following steps: proportionally mixing the alkylol amine composition, anhydrous sodium sulfate, acetic acid, sodium gluconate, glycerol, molasses and water, and sufficiently stirring at normal temperature under atmospheric pressure. The cement grinding aid is suitable for Portland cement, composite cement, slag cement and various other cement species, and is especially suitable for cement with insufficient later strength or heavily-doped limestone cement; and the cement grinding aid can obviously enhance the cement grinding efficiency, lower the energy consumption, effectively enhance the 3-day and 28-day compression strength of cement and especially enhance the 28-day compression strength by 5-10 MPa.

The invention relates to an antibacterial cement mortar and its preparation and application method. The raw material ratio of the antibacterial cement mortar is: 9.5-14 parts of cement, 0.5-1 part of metakaolin, 25-48 parts of quartz sand, antibacterial 0.01 to 0.03 parts of antibacterial agent, 5 to 9 parts of deionized water; the present invention selects different nanometer photocatalyst materials to mix as antibacterial main ingredients to ensure the stability of antibacterial effect; antibacterial agents are respectively attached to the surface of quartz sand, dispersed in cement and The method of mixing the three in deionized water is used to prepare antibacterial cement mortar, which reduces the uneven dispersion and material loss caused by a single method of incorporation, and at the same time ensures the dispersion and reactive sites of antibacterial agents in cement mortar The number of exposures to achieve the purpose of effective antibacterial.

The invention discloses a preparation method of a polycarboxylate water reducer for concrete prefabricated components, which comprises the following steps: mixing unsaturated polyoxyethylene ether macromonomers with deionized water, stirring evenly, adding an initiator, and continuing Stir; mix unsaturated carboxylic acid, chain transfer agent, monoethanolamine fumarate, reducing agent and deionized water, and stir evenly to prepare a mixed solution, gradually add the mixed solution to the above steps, and the dropwise addition is completed Finally, react for 2 to 4 hours, then add water to adjust the solid content of the system to obtain the mother liquor of polycarboxylate superplasticizer; dilute the mother liquor of polycarboxylate water reducer with water to a mass concentration of 20%, and then mix it with melamine and antifoaming agent are compounded to obtain a polycarboxylate water reducer for concrete prefabricated components. The water-reducing agent has simple preparation process, high water-reducing rate and excellent slump-preserving performance, can greatly increase the early strength and later strength of concrete, and can improve the surface smoothness of concrete products.

The invention discloses a preparation method of an early-strength polycarboxylate water reducer, comprising the following steps: (1) mixing polyether monomers and deionized water, stirring evenly, heating to 30°C, and then adding an initiator , continue to stir; (2) mix alcohol amine fumarate, acrylic acid, chain transfer agent, reducing agent, and deionized water, stir evenly, make a mixed solution, and add the mixed solution dropwise to step (1) (3) After the dropwise addition is completed, the reaction is carried out at 30°C for 2 to 4 hours, and then water is added to adjust the solid content of the system to obtain an early-strength polycarboxylate superplasticizer. The water-reducing agent obtained according to the preparation method disclosed in the present invention has a high water-reducing rate, good slump retention, can greatly improve the early strength, and has a relatively high later strength, and can be applied to pipe piles and prefabricated components that need to improve the early strength and other concrete products.

The invention discloses a preservative special for pozzuolana concrete. The preservative is prepared from silica fume, coal ash, sodium carboxymethylcellulose, a water reducer, latex powder, polyvinyl alcohol and triethanolamine. The preservative is particularly prepared from the following raw materials in parts by weight: 90-110 parts of silica fume, 5-20 parts of coal ash, 0.6-1.0 part of sodium carboxymethylcellulose, 1.0-2.0 parts of the water reducer, 1.0-2.0 parts of redispersible latex powder, 1.0-2.0 parts of solid polyvinyl alcohol and 0.1-0.5 part of solid triethanolamine; and 10%-20% of the preservative is mixed into mortar or concrete according to the weight of pozzuolana. Compared with the prior art, the preservative has the advantages that a certain amount of triisopropanolamine is doped as a concrete early strength agent, compared with sulfate and chlorine salt early strength agents, triisopropanolamine has the advantages that triisopropanolamine can be well fit with additives and has stable early strength, and the setting time and the durability are not influenced, so that the early strength of the pozzuolana concrete can be effectively improved, and the durability of the concrete can be improved.

The invention discloses an embedded device for electrochemically detecting or repairing reinforcing bars in concrete. The embedded device comprises a joint, a positioner, a clamp and a conductive rod, wherein the joint comprises an outer sleeve and a conductive block; the outer sleeve is fixed on the positioner; the positioner is fixedly connected with the clamp; the conductive block is arranged in the outer sleeve and is electrically connected with the conductive rod and the clamp. The embedded device is simple in structure and convenient to install; after the device is installed, during the service of a structure, the conductive rod is inserted to enable the structure to be electrically communicated with the reinforcing bars; by virtue of electrochemical detection equipment, the reinforcing bars in the concrete can be electrochemically tested or dechlorinated and repaired by using various electrochemical testing methods, rich electrochemical parameters are obtained, and a corrosion state of the reinforcing bars is accurately mastered; the whole operation process is simple and quick, a concrete protection layer does not need to be broken in advance, the later-stage detection cost of the structure is saved, and the durability of the reinforcing bars is not influenced.