464 results about "Polytetrafluoroethylene sheet" patented technology

An ink-jet recording oil-based ink which has satisfactory pigment dispersibility both at the beginning of storage and even during long-term storage and provides excellent spouting stability without being influenced by temperature changes in printing circumstances. The ink comprises a pigment; a dispersing agent comprising a reaction product of a polyamine compound and a self condensation product of 12-hydroxystearic acid; a saturated hydrocarbon solvent comprising a liquid paraffin as a main component; and a vegetable oil, the ink having a surface tension of 26 to 30 dyne / cm at 25° C. and a contact angle on a polytetrafluoroethylene plate of 40° to 50° at 25° C., and satisfying the following relationship:wherein WHC is the weight of the saturated hydrocarbon solvent and WVC is the weight of the vegetable oil.

This invention concerns a method of manufacturing a highly conductive polytetrafluoroethylene sheet; a method of manufacturing a highly conductive unsintered polytetrafluoroethylene sheet: and a method of manufacturing a highly conductive sintered sheet. In the first method, a paste of polytetrafluoroethylene powder admixed with conductive substance and extrusion lubricant is extruded to preform an unsintered tube-like material, and at least one place on the circumference of this extruded material, the material is cut open longitudinally and the resulting sheet is calendered if necessary. The second method includes a sintering process for the sheet. This invention also concerns a highly conductive polytetrafluoroethylene sheet having a wide-width and long-length, which is obtained by the above-mentioned method. This sheet is not less than 170 mm in width and has variance of volume resistivity (conductivity) in the longitudinal direction, 10% or less, preferably 7% or less in the cross direction. This invention can provide a highly conductive wide-type PTFE sheet whose conductivity in the longitudinal direction is nearly uniform in the cross direction.

The invention belongs to the technical field of crystal growth and relates to a growth method of organic nonlinear optical crystal. The growth method comprises the following steps of: firstly, drying a DAST (sulfur trifluoride) crystal growth raw material, dissolving the DAST crystal growth raw material in an absolute methanol solution to prepare a DAST methanol solution; then, heating and filtering the DAST methanol solution, and transferring the DAST methanol solution into a wild-mouth bottle; putting a polyfluortetraethylene plate in the wild-mouth bottle, and sealing the wild-mouth bottle; putting the wild-mouth bottle in a sealed water bath heating device to be thermally insulated, and cooling the wild-mouth bottle until the DAST crystal stops growing, taking out the crystal DAST crystal, namely, obtaining the DAST crystal with large surface area and thickness. The growth method is simple, the principle is scientific, the growth environmental is friendly, the cost is low, and the grown DAST crystal is large in geometric dimension, high in transmittance and convenient to be further processed and utilized.

The present invention discloses a compounded full-solid polymer electrolyte for secondary lithium cell and its preparation method. The described polymer electrolyte contains 2%-30% of inorganic oxide, and the matching ratio of polyethylene glycol and alkali metal salt O / Li is 8-16. Its preparation method includes: dissolving polyethylene glycol and LiClO4 in acetionitrile, adding inorganic oxide,pouring the mixed solution onto teflon plate, evaporating solvent and drying at 50-100 deg.C in vacuum drying box. The described inorganic oxide also can be modified inorganic oxide. Said prepared material can be extensively used in the fields of handset, domestic appliances and electric car.

The invention discloses a polyurethane elastomer material with the wide temperature range and the high damping capacity and a preparation method thereof. The preparation method comprises the steps that polyester diol and a diisocyanato raw material are adopted to react with each other to prepare a polyurethane prepolymer, the polyurethane prepolymer is poured into a polytetrafluoroethylene plate mold by taking an HDI trimer as a cross-linking agent and taking a raw material containing dynamic reversible disulfide bonds as a chain extender to remove bubbles, and heat preservation and curing molding are conducted. According to the polyurethane elastomer designed and synthesized based on the molecular structure, the damping factor tan<delta> is larger than 0.3 when the temperature of the damping material exceeds the temperature range of 220 DEG C (minus 50 DEG C-178 DEG C), and the damping factor tan<delta> is larger than 0.4 when the temperature of the damping material exceeds the temperature range of 200 DEG C (minus 44 DEG C-165 DEG C); the polyurethane elastomer material has the good high-low temperature damping property and can be expected to be widely applied to the damping and noise reducing aspects in the fields of building materials, automobiles, national defense, aerospace and the like.

The invention discloses a preparation method of a nano cellulose composite film, relates to a preparation method of a composite film, and is used for solving the problem that a film prepared by using the prior art is low in tensile strength. The preparation method of the nano cellulose composite film comprises the following steps: 1, preparing nano cellulose hydrosol by adopting a method for hydrolyzing cellulose with strong acid; 2, weighing and mixing poval, polyacrylamide, glycerol, nano cellulose hydrosol and deionized water to obtain a mixed solution, stirring for 2-4 hours in water bath, carrying out ultrasonic treatment, and then carrying out vacuum debubbling so as to obtain a nano cellulose film-forming liquid; and 3, carrying out scrape coating on the film-forming liquid obtained in the step 2 by adopting a scrape coating method on a polytetrafluoroethylene plate, and drying at room temperature to obtain the nano cellulose composite film. The preparation method is simple in process, easy to operate and low in cost; and the maximum tensile strength of the prepared nano cellulose composite film can reach 66.57MPa and is improved by 69.17% as compared with a poval film. The preparation method is used for preparing the nano cellulose composite film.

A method for manufacturing an expanded polytetrafluoroethylene (PTFE) plate comprises the following steps: sieving PTFE dispersion resins, adding a propellant and mixing the two materials, placing the mixed materials for 24h and then carrying out aging treatment, then carrying out pre-press shaping and extruding blanks, carrying out calendaring with two rollers, removing the propellant, carrying out composite shaping after biaxial tension and carrying out reshaping and trimming to finally manufacture the expanded PTFE plate. The expanded PTFE plate is a great breakthrough in the manufacturingprocess of molded plates and turning plates. The compression resilience, the tensile strength and the low stress relaxation rate of the expanded PTFE plate are obviously increased and the expanded PTFE plate obviously improves the performance defects of the fluoroplastics, thus meeting the demand of the use functions of the sealing elements and propelling the fluoroplastics to be one of the substitutes of the asbestos materials widely used at present in the sealing material field.

The invention discloses an LFBB (Low Frequency Broadband) dual-polarization four-ridge horn antenna, which mainly solves the problems that the test requirement of a low-frequency antenna cannot be met by the prior art, the low-frequency antenna is very heavy and not easy to move and rotate, and the processing is difficult. The LFBB dual-polarization four-ridge horn antenna comprises an antenna wall (1), ridges (2), a short-circuit board (3), coaxial connectors (4), feed probes (5), a PTFE (Poly Tetra Fluoro Ethylene) board (6), short-circuit pins (7), a rectangular groove (8), a cylindrical groove (9) and transition cones (10), wherein the inner walls of four ridges (2) adopt hollow structures, the top part of each ridge is provided with a cutting angle, the PTFE board (6) is fixedly arranged at the middle part of the four ridges (2), one side of the short-circuit board (3) is provided with the rectangular groove (8), the top part of each feed probe (5) is of a conical structure, and the surface of the tail end of each feed probe (5) is plated with a flexible conducting material such as silver or tin. The LFBB dual-polarization four-ridge horn antenna disclosed by the invention has the advantages that the weight is light, the structure is stable, and the lowest frequency can be stabilized at 75 MHz; and the LFBB dual-polarization four-ridge horn antenna is suitable for a source antenna in low-frequency antenna test.

The invention discloses an edible protein / polysaccharide composite membrane and a preparation method and application thereof.The composite membrane is prepared through the method that a Curdlan solution, a carboxymethyl chitosan solution and plasticizer glycerinum are added into a protein solution including one of soybean protein, casein and whey protein, the pH value of the mixed liquid is adjusted to be 5-8; ultrasonic degassing is conducted, MTG is added, and membrane-forming liquid is acquired; the membrane-forming liquid is poured into a polyfluortetraethylene plate, a reaction is conducted for 30-60 minutes at the temperature of 55-65 DEG C, sizing and sterilization are conducted, 4-DEG C cooling is conducted for 10-20 minutes, drying is conducted under the conditions that RH is 30-50% and the temperature ranges from 20 DEG C to 30 DEG C, and then membrane uncovering is conducted.The heat stability of the membrane is improved by adding Curdlan into the common edible protein solution, chitosan is added so that the membrane can have the antibacterial performance, microorganism source transglutaminase is added to catalyze the protein and cross linking between the protein and chitosan, and the chemical performance of the membrane is improved.

The invention discloses a chitosan-furfural residue nano-fiber composite membrane preparation method mainly comprising the following steps: furfural residue nano-cellulose is prepared, and a 1-10% nano-cellulose suspension liquid and a 1wt% chitosan acetic acid solution are prepared; the nano-cellulose suspension liquid is added into the chitosan acetic acid solution, and magnetic stirring is carried out for 1.5h; when the material is dissolved, ultrasonic dispersion is carried out for 30min; after vacuum degassing, the mixed solution is spread on a polytetrafluoroethylene plate with a flat surface; the solution is dried for 72h under vacuum and under a temperature of 45 DEG C; an obtained membrane is soaked in a 0.5mol / L NaOH solution for further neutralization; deionized water is used for washing; and the membrane is dried, such that the chitosan-furfural residue nano-fiber composite membrane is obtained. The method has the advantages that: no expensive equipment such as high-pressure homogenization equipment is needed, such that production cost is reduced; problems such as low mechanical strength and poor water resistance of chitosan membrane are solved; no complicated modification operation upon chitosan is needed, and the composite material with excellent performance can be obtained by simply adding natural high-molecular fiber.

The invention discloses a production process and device of an expanded polytetrafluoroethylene board. According to the technical scheme, the production process is characterized by comprising the following steps: screening refrigerated polytetrafluoroethylene dispersion resin, adding additives according to a ratio, ripening the mixed raw materials to obtain a blank, extruding the blank to form a rod material, rolling the rod material through a two-roller shaft to form a flaky film, degreasing, drying and stretching the flaky film, longitudinal and transversely drawing the flaky film, laminating the flaky film which is drawn in two directions, pressing the flaky film to obtain a sheet, and finally trimming the sheet to obtain the board. The production process of the expanded polytetrafluoroethylene board breaks through a traditional board production process, the problems of creeping and cold flow of an ordinary board can be solved, the compression resistance, the creeping loosening rate, the compression rate, the resilience property and the like of the expanded polytetrafluoroethylene board are obviously improved, and the expanded polytetrafluoroethylene board can be widely used for sealing aerospace, medical, food and petroleum pipelines and the like and has extremely good application temperature, an anti-aging property, no toxicity, no pollution and the like.

The invention discloses a polysaccharide-base gel composite film, and a preparation method and application thereof. The preparation method comprises the following steps: adding a Curdlan solution, a sodium carboxymethyl cellulose solution and glycerol into any one or two of an edible polysaccharide-sodium alginate solution and a carrageenin solution, and regulating the pH value of the mixed solution to 4-8 to obtain a film forming solution; carrying out ultrasonic degassing, and pouring into a teflon plate; setting, carrying out sterilization treatment, cooling at 4 DEG C for 10-20 minutes, and carrying out drying and film peeling under certain conditions; and after the film is peeled, immersing the film in any one or two of a KCl solution and a NaOH solution for 5-20 minutes, and naturally airing. Common polysaccharide substances in food are used as the matrix, the glycerol is used as the plasticizer, and the Curdlan and sodium carboxymethyl cellulose are added to prepare the composite film. The composite film has the advantages of favorable mechanical properties, favorable water tightness and favorable heat stability, and is green, environment-friendly and edible.

The invention discloses edible composite cling film, and a preparation method and application thereof. The composite film is prepared by the following steps: adding a polyvinyl alcohol solution, a chitosan solution, a phenolic acid substance and a plasticizer in an edible polysaccharide Curdlan suspension, adjusting the pH value of the mixed solution to 3-5, carrying out ultrasonic degassing to obtain a film-forming liquid, pouring the film-forming liquid into a polytetrafluoroethylene plate, carrying out heat preservation for carrying out a reaction for 8-10 minutes at a temperature of 90-120DEG C, carrying out sizing, carrying out sterilization treatment, carrying out ultraviolet irradiation treatment for 5-10 minutes, carrying out hot-air circulating drying treatment at a temperature of 90-120 DEG C for 30-60 minutes, and carrying out cooling at a temperature of 4 DEG C to obtain the edible composite cling film. The edible composite film provided by the invention has the advantagesof high tensile strength and high extensibility, has excellent integrity, tensile strength and extensibility after being stewed in boiling water for 1 hour, and can effectively prolong the shelf lifeof fruits, vegetables and the meat products.

The invention relates to a steel structure hoisting slide support seat with large span and a construction process thereof. The steel structure hoisting slide support seat with large span comprises a support boss surface steel plate platform, wherein the support boss surface steel plate platform is welded and fixed with a lower pre-embedded steel column angle groove by a high-strength bolt; a slide steel plate base is arranged on the support boss surface steel plate platform and connected and fixed with the support boss surface steel plate platform through steel columns; a gap between the support boss surface steel plate platform and the slide steel plate base is filled by high-strength grouting materials; an upper slide steel plate is arranged on the slide steel plate base; the top of theupper slide steel plate is provided with a polytetrafluoroethylene plate; the top of the polytetrafluoroethylene plate is provided with a reinforcing steel plate, and one side of the reinforcing steel plate is provided with a slide steel plate. The invention has reasonable design, safety, reliability and high construction speed and successfully solves the problem of hoisting of a steel truss structure with large span under the condition of unstable deviation of a support boss.

A solid polymer electrolyte composite for an electrochemical reaction apparatus that possesses satisfactory ion conduction properties and has excellent mechanical strength and heat resistance, is provided. the solid polymer electrolyte composite is characterized in that a solid polymer electrolyte is contained in the continuous pores of an expanded porous polytetrafluoroethylene sheet which has continuous pores and in which the inner surfaces defining the pores are covered with a functional material such as a metal oxide. An electrochemical reaction apparatus containing an electrolyte, wherein said electrochemical reaction apparatus is characterized in that the aforementioned solid polymer electrolyte composite is used as this electrolyte is also provided.

The invention relates to a preparation method of a novel polyether copolyamide gel membrane, belonging to the field of membrane separation technologies. The preparation method of the gel membrane comprises the following steps of mixing and stirring polyether copolyamide, surfactant and solvent at a certain temperature so as to obtain casting film liquor, coating the casting film liquor on a teflon plate, standing in air for a while, then drying in a vacuum drying oven for several hours, and obtaining the polyether copolyamide gel membrane. The polyether copolyamide gel membrane prepared by the method not only has excellent tensile strength and elongation at break, but also has high permeation flux and separation factor, and is especially suitable for separation of carbon dioxide and hydrogen and recycling of organic steam such as benzene and methane.

The utility model relates to a multifunctional bridge shock-absorbing and isolating support, which is composed of upper and lower parts. The upper part is composed of PTFE plate sliding bearings, which can realize the free expansion and displacement of the main beam structure under conventional loads, and thus have all the characteristics of conventional sliding bearings. The lower part is a combined shock-absorbing and isolating device with multi-level shock-absorbing and isolating functions, which is composed of a lead rubber pad in the middle part and an elastic-plastic energy-dissipating soft steel plate in the peripheral part. A lead core is arranged in the middle of the lead core rubber pad. Under earthquake action, lead rubber pads and elastic-plastic energy-dissipating steel plates are used to jointly dissipate energy to effectively limit the relative displacement between beams and piers. A rigid connection is made between the sliding support of the polytetrafluoroethylene plate and the combined shock-absorbing and isolating device to ensure the joint work of the upper and lower parts of the device. With the worldwide emphasis on the anti-seismic fortification of engineering structures and the continuous development of the economic level, this new type of bridge anti-seismic bearing will have a wide range of engineering application prospects.

The invention discloses a preparation method of a polyurethane pervaporation phenol / water separating membrane compounded by inorganic particles, and belongs to the field of pervaporation membrane separation. The polyurethane membrane basic material is obtained by polymerizing and mixing monomer hydroxyl-terminated polybutadiene, toluene diisocynate, 4,4'-diamine diphenylmethane solution, cyclodextrin and silica or carbon fiber powder. The preparation method comprises the following steps: reacting hydroxyl-terminated polybutadiene with toluene diisocynate to obtain blocked prepolymer, then adding 4,4'-diamine diphenylmethane solution and cyclodextrin as chain extenders to perform the chain extension, and adding inorganic modified particle silica or carbon fiber powder (using N,N-dimethylacetamide as solvent) to obtain prepolymer solution of polyurethane; casting the solution on a polyfluortetraethylene plate to form a membrane, solidifying for 1-1.5 hours at room temperature, and moving the membrane to an oven at 80 DEG C to thermally treat to obtain the polyurethane membrane compounded by inorganic particles. The preparation method disclosed by the invention is simple in process, and the prepared membrane has good heat and chemical stability and mechanical property.

The invention relates to a damper with vibration energy dissipated through a soft steel surface internal yield deformation mechanism. The damper is used for energy dissipation and vibration reduction of a house building. An assembly type soft steel damper optimized through an equal-stress line comprises a soft steel energy dissipation piece, an anti-buckling clamping plate, L-shaped connecting plates, anchoring steel plates, a polyfluortetraethylene plate, pre-pressing fastening bolts, friction type high-strength connecting bolts, a limiting bolt, embedded anchoring steel bars and flexible filling materials. The assembly type soft steel damper optimized through the equal-stress line can serve as a dividing element of a building to be installed in a structure and does not bear a vertical load; when the assembly type soft steel damper bears a wind load or an earthquake load, the elastic-plastic hysteretic behavior generated when the soft steel energy dissipation piece deforms dissipates the energy input by the wind load or the earthquake load, and thus main components of the structure are protected; the soft steel energy dissipation piece is optimized through the equal-stress line, so that accumulated plastic deformation of the energy dissipation piece is greatly reduced, and the low cycle fatigue performance of the energy dissipation piece is enhanced.

This invention discloses a hyperbolic steel support used in engineering structure including a cover, a core at the lower surface of the hyperbolic surface, a base seat and a fixed box of its reentrant at the upper surface of the core between the top cover and base seat keying together the lower part of the cover and upper part of the base seat, a flexible absorber is between the surrounding sidewall of the top cover and fixed box having a guide rail at the bottom to make the base seat slide on it only. There are Teflon boards between top cover and core, base seat and fixed box bottom, and core and the base seat, sealing plates seal the open-end at top of the fixed box cover and three siamese sealing rings sealing between the cover and base seat.

Belonging to the technical field of pervaporation membrane separation, the invention relates to a preparation method of a modified polyurethane pervaporation phenol / water separation membrane. The preparation method of the membrane consists of: reacting hydroxyl-terminated polybutadiene with diisocyanate to obtain a terminated prepolymer, adding diamine and cyclodextrin as a chain extender for chain extension, and taking N, N-dimethyl acetamide as a solvent to obtain a modified polyurethane solution, carrying out membrane casting on the solution on a polyfluortetraethylene plate, and conducting curing at room temperature for 1 to 1.5 hours, then moving the obtained membrane into an oven at a temperature of 80DEG C for 10-15 hours of heat treatment, thus obtaining the modified polyurethane membrane. The material synthesis and membrane preparation process of the invention is simple, and the prepared membrane has good thermal and chemical stability as well as mechanical properties. Moreover, compared with traditional unmodified polyurethane separation membranes, the membrane prepared in the invention, due to the existence of the modifier cyclodextrin, has a better comprehensive separation effect on phenol in a phenol / water mixed solution, and has a great practical value.

The invention relates to a preparation method for a multi-state electrochromic device, which belongs to the technical field of functional materials and devices. The preparation method comprises the following specific steps: 1) preparing electrolyte solution; 2) cutting two transparent conductive substances and a polytetrafluoroethylene plate with the width which is equal to the width of the transparent conductive substances, the length which is 3-7mm less than the length of the transparent conductive substances, and the thickness of 0.3-0.7mm, forming a square through hole in the middle of the polytetrafluoroethylene plate, the distance from the edge of the through hole to the edge of the corresponding polytetrafluoroethylene plate being 3-7 mm, washing and drying for the future use; 3) spin-coating a base metal oxide nano-particle dispersion liquid on one substrate conductive layer, and then sintering; 4) bonding the polytetrafluoroethylene plate on the substrate conductive layers which are not spin-coated, pouring the electrolyte solution in the through hole, then bonding the spin-coated substrate conductive layers towards the through hole, two substrates being staggered at a distance of 3-7mm in a long side direction and completely covering the polytetrafluoroethylene plate, and finally encapsulating by epoxy resin. The electrochromic device prepared by the preparation method disclosed by the invention is capable of realizing transparent, mirror-surface and black three-colour-state reversible conversion.

The invention discloses a fluorescent sensor for measuring the picric acid content. A fluorescent carrier in a film substrate monomer is an allyl four iodine fluorescein. 15mg of fluorescent carrier allyl four iodine fluorescein is dissolved in 0.2ml of N, N-dimethylformamide for sufficient dissolution, 200mg of acrylamide, 0.4ml of hydroxyethyl methylacrylate, 0.15ml of cross-linking agent triethoxy trimethyl acrylate and 0.2ml of triethanolamine are added, finally 0.25ml of 1-oxhydryl cyclohexyl phenyl ketone is added for even mixing; and a solution is removed to drop on a Teflon plate, a quartz slide subjected to silanization is covered on the Teflon plate, an ultraviolet lamp is used for irradiating for 20 minutes, and drying is carried out at a room temperature. The sensor has the advantages of simple preparation, good stability, short response time, good reproducibility and the like, and can continuously and timely measure the picric acid content on line.

There is a method for producing plastic which can be degraded by visible light catalyzing, it uses TiO2 / organic dye as catalyzer, TiO2 / organic dye and plastic are blended and dissolved in four hydrogen furan, following the liquid is dropped onto poly-tetrafluoro ethylene board, it is taken off after it is air-dried naturally, and then the visible light catalyzer degraded plastic is obtained.

The invention belongs to the technical field of electrochemistry power supply, and more specifically relates to a preparation method of a three-dimensional composite metal lithium anode all-solid-state lithium ion battery. According to the preparation method, metal lithium is loaded onto a carrier material through chemical methods including electrochemical deposition or fusion penetration or physical methods so as to obtain a three-dimensional composite metal lithium anode; the carrier material is active carbon fiber cloth; a PMMA-PEI based all-solid-state polymer electrolyte membrane is prepared, is peeled off from the surface of a polyfluortetraethylene plate, and is cut into pieces of appropriate sizes for further processing; LiFePO4 is taken as a cathode, assembling is carried out based on a cathode-PMMA-PEI based all-solid-state polymer electrolyte membrane-three-dimensional composite metal lithium anode sequence so as to obtain all-solid-state lithium ion button cells. The three-dimensional composite metal lithium anode is high in specific energy, coulombic efficiency, safety performance, is table in electrode interfaces, assembling process of the all-solid-state lithium ionbatteries is simple, and is convenient to control.

The invention discloses a method for preparing a polytetrafluoroethylene super-hydrophobic coating. According to the super-hydrophobic coating, in actual application, the contact angles between water drops and the surface are 150-165 degrees, the rolling angles of the water drops on the surface of a material are smaller than 10 degrees, and the polytetrafluoroethylene super-hydrophobic coating has good hydrophobicity. The method for preparing the polytetrafluoroethylene super-hydrophobic coating comprises the steps of adopting a supercritical method, placing a polytetrafluoroethylene plate and a substrate in a reaction kettle with a heating device, leading gas into the kettle, controlling temperature and pressure, causing the led-in gas to be in a super-critical state, maintaining pressure for 12-120 h, performing decompression cooling, and obtaining a super-hydrophobic polytetrafluoroethylene plate and a super-hydrophobic substrate. The inner wall of a metal pipe connected with a pressure release valve and the inner wall of a container are also super-hydrophobic. The method for preparing the super-hydrophobic coating is simple, practical and free of solvent in preparation process and facilitates large-scale production.

The invention discloses a rotary oil seal of a multi-head spiral oil return line, which comprises a rubber body, a skeleton and a seal lip. The rubber body, the skeleton and the seal lip are integrated, the seal lip is made from a polytetrafluoroethylene sheet, and the contact surface of the seal lip made from the polytetrafluoroethylene sheet and a shaft is provided with 2-7 spiral oil return lines of which the direction of rotation is in accordance with that of the shaft and intersected with the end of the polytetrafluoroethylene sheet for making the seal lip. By adopting the deign of multi-head helical line, the invention has the advantages of big oil return capability, reliable seal, long service life, energy conservation and environment protection, and is capable of preventing the entry of dust.

The invention discloses the form of a seismic isolation foundation for a bridge. A bearing platform of the bridge is divided into a bridge pier bearing platform and a pile foundation bearing platform in the height direction from top to bottom; the bridge pier bearing platform is integrated with a bridge pier; the pile foundation bearing platform is integrated with a pile foundation; a rectangulargroove is formed on the top of the pile foundation bearing platform; a seismic isolation support is laid at the bottom of the groove; the upper part of the seismic isolation support is used for bearing the bridge pier bearing platform; a cofferdam type protective layer is arranged on the outer side of the pile foundation bearing platform; a buffer rubber plate is arranged on the inner side of theprotective layer in the longitudinal bridge direction; a polytetrafluoroethylene plate is arranged on the inner side of the protective layer in the horizontal bridge direction; the seismic isolation support consists of a lower connecting steel plate, a lower sleeve, a lower anchor rod, a lower anchoring bolt, an upper connecting steel plate, an upper sleeve, an upper anchor rod, an upper anchoring bolt and a support body which is positioned between the lower connecting steel plate and the upper connecting steel plate; and the support body is formed by bonding a rubber sheet, protective layer rubber, a stiffening steel plate and a support connecting steel plate in a lamination vulcanization mode. According to the seismic isolation foundation, due to the seismic isolation function of the seismic isolation support, a bridge beam structure above a seismic isolation layer is isolated from a horizontal seismic oscillation component, so that the seismic performance of the bridge is improved.

The invention discloses a self-balancing test device and a method for directly testing axial tensile strength of early-age concrete. The testing device consists of an outer framework, an inner template, a dowel bar, a hydraulic hollow jack, a hollow load sensor, a ball hinge, a lock nut, a polyfluortetraethylene plate, a hydraulic oil pump and a resistance strain gauge. When testing, a side template in the inner template is removed, and an end template in the inner template and a side plate in the outer framework which are fixed are loosened; the dowel bar is fixed in the center of the end template in the inner template; the hydraulic oil pump drives the hydraulic hollow jack; and the end template and the hydraulic hollow jack move together to break a concrete test piece to test the axial tensile strength of the early-age concrete. The testing device has simple structure, convenient assembly and disassembly and less required materials and equipment, and is suitable for scientific research and testing the axial tensile strength of the early-age concrete in construction site.