620results about How to "Reduce rust" patented technology

An air movement and air cleaning system which includes an air movement system preferably including fan and fan housing to prevent thermal gradients in a building or room, in combination with an air cleaning surface of at least titanium dioxide, to react with moisture in the air and an ultraviolet light source in close proximity to the air cleaning surface, such that as humidity in the air passes through the air movement system over the titanium dioxide, the ultraviolet light creates hydroxyl radicals in the presence of the titanium oxide catalytic surface thereby purifying the air that passes therethrough.

The invention discloses an acid-resistant and alkali-resistant waterborne damping coating with a wide temperature range and high damping capacity, comprising, by weight, 30-65 parts of a waterborne emulsion, 15-45 parts of a filler, 10-35 parts of a flame retardant, 0.1-2 parts of fibers, 0-5 parts of a film-forming agent, 0.1-1.5 parts of a dispersing agent, 0.1-1.5 parts of a defoaming agent, 0-4 parts of an antifreeze agent, 0.2-3 parts of a thickening agent and 1-8 parts of a multifunctional aid. The acid-resistant and alkali-resistant waterborne damping coating with wide temperature region and high damping capacity has the advantages that the acid-resistant and alkali-resistant waterborne damping coating is high in damping performance, wide in damping temperature range and excellent in acid resistance and alkali resistance; loss factors of materials in the temperature range ranges from -30 DEG C to 50 DEG C reach 72 hours as shown by acid-resistant and alkali-resistant tests on the materials by the aid of 10% NaOH solution and 10% H2SO4 solution, and the acid-resistant and alkali-resistant waterborne damping coating is free of foaming, softening and sticking and excellent in acid resistance and alkali resistance.

The invention belongs to the technical field of light gas gun experiments, and particularly relates to a light gas gun driven through hydrogen and oxygen mixed gas detonation, in particular to a two-stage light gas gun driven through hydrogen energy. According to the technical scheme, the two-stage light gas gun driven through hydrogen energy comprises a combustor, a gas injection device, an ignition device, a pump pipe, a high-pressure cone section, a transmitting pipe, a target chamber and a magnetic speed testing device, wherein the ignition device is installed at one end of the combustor, the other end, opposite to the end with the ignition device, of the combustor is connected with the pump pipe, and a pump pipe membrane and a pump pipe membrane breaker are arranged at the junction; the gas injection device is used for injecting hydrogen, oxygen and inert gas into the combustor; a piston is arranged in the pump pipe; the large-diameter portion of the high-pressure cone section is connected with the pump pipe; the small-diameter portion of the high-pressure cone section is connected with the transmitting pipe, and a transmitting pipe membrane and a transmitting pipe membrane breaker are arranged at the junction; shots are arranged in the transmitting pipe, and one end of the transmitting pipe is located in the target chamber; and the magnetic speed testing device is installed at the tail end of the transmitting pipe and connected with an oscilloscope. The two-stage light gas gun is driven through hydrogen energy instead of gunpowder, damage to the gun is small, no particular product is generated, and a gun barrel can be cleaned conveniently after experiments.

The invention provides a freon-free environment-friendly continuous casting slag which comprises the following ingredients by the weight percentage of 3 to 15 percent of Na2O, 3 to 12 percent of MgO, less than 8 percent of Al2O3, 2 to 9 percent of B2O3, 1 to 15 percent of C and the balance of CaO and SiO2, wherein the CaO and SiO2 account for 1.1 to 1.5 percent; and the sum of Na2O and MgO in the casting slag is more than 10 percent; in addition, the freon-free environment-friendly continuous casting slag can also comprise Li2O which accounts for not more than 3 percent. The freon-free environment-friendly continuous casting slag uses merwinite and miserite instead of cuspidine, is free of Freon, and has a value in environment protection and reduction of corrosion of equipments and much higher than the slight increase of raw material cost. The casting slag can be used industrially in batch.

A method for controlling iron scale structures of hot-rolled steel bars by stepped cooling belongs to the technical field of steel rolling. Compact iron scale structures are obtained through optimization of a rolling and cooling process, so that a problem that steel bars produced by a post-rolling forceful through-water process are fast in corrosion rate and serious in corrosion degree in atmosphere is solved, and a goal that rust is relieved within a period of time is achieved. By adopting a stepped cooling process and the method for controlling the iron scale structures, provided by the invention, a traditional through-water cooling process can be replaced, so that mechanical property of an HRB400 (hot-rolled ribbed bar)-grade steel bar with phi 20 to 25 mm of a typical specification meets requirements of various technical indexes of GB 1499.2-2007; meanwhile, when being delivered to a cooling bed, each of all hot-rolled high-strength steel bars produced by adopting the stepped cooling process does not have a surface red Fe2O3 rust layer; shown by SEM (scanning electron microscope) analysis, iron scale is 10 to 30 [mu]m thick; after staying for one month in the open air, corrosion area of a sample is reduced by 50 percent in comparison with that of a steel bar produced by a traditional forceful through-water process.

The invention discloses a square steel pipe fabricated column-prefabricated superposed beam integrally-fabricated frame and a construction method. The frame comprises a square steel pipe with inner and outer ribs, a square steel pipe casing with connecting wing plates and a prefabricated superposed beam. The square steel pipe is formed by rolling once, a thin centrifugally-produced concrete protective wall is arranged inside the square steel pipe, and high-performance concrete wraps the square steel pipe, so that a square steel pipe fabricated column is formed. The square steel pipe casing with the connecting wing plates is used for vertical connection between one upper square steel pipe fabricated column and one lower square steel pipe fabricated column as well as connection between the prefabricated superposed beam and the square steel pipe fabricated column. Short I-beams are arranged at the ends of the prefabricated superposed beam, and the prefabricated superposed beam is connected with the connecting wing plates on the square steel pipe casing through high-strength bolts. An engineered cementitious composite or fiber reinforced cement composite is poured in beam-column joint connection areas. The concrete fabricated superposed beam is connected with prefabricated floor slabs as well as the prefabricated floor slabs are connected both through fiber reinforced composite plastic boards. A prefabricated house has the advantages of reasonable stress, convenience in construction, high joint ductility, good endurance and anti-seismic performance and the like.

The invention provides a post-rolling control cooling process for hot-rolled H-shape steel. The hot-rolled H-shape steel enters a cooling device after the rolling is finished, an upper nozzle and a lower nozzle are respectively aligned with upper / lower R parts of the hot-rolled H-shape steel to carry out water spray cooling, and a left nozzle and a right nozzle are respectively aligned with left / right flank centers of the hot-rolled H-shape steel to carry out water spray cooling. The invention is characterized in that the pressure of cooling water is within 0.7 to 1.2MPa, the water quantity is within 1,200 to 2,000m3 / hour, the cooling rate is within 75 to 150 DEG C / s and the cooling time is within 3 to 5 seconds; and the hot-rolled H-shape steel is cooled to 20 to 30 DEG C above the martensitic phase transformation point of the corresponding steel grade after the rolling under the temperature of 850 to 1,000 DEG C is finished. By adopting the cooling process in the invention, the actual grain size of ferrite at the core part of the hot-rolled H-shape steel can be refined from 8-10 grades to 10-12 grades, and a tissue of bainite plus sorbite can be formed on the surface of the hot-rolled H-shape steel, thereby obviously improving the strength and toughness of the hot-rolled H-shape steel and improving the yield strength of the hot-rolled H-shape steel by more than 70MPa.

The invention discloses a prefabricated assembly FRP-reinforcing steel-bar-concrete combined bridge deck and a construction method. The prefabricated assembly FRP-reinforcing steel-bar-concrete combined bridge deck comprises a semiclosed FRP groove and concrete inside the FRP groove, wherein the bottom surface and two side surfaces of the concrete are wrapped by the FRP groove to form the combined panel, a transverse through reinforcing steel bar reserved tunnel is formed in a transverse setting position of the combined panel, a transverse prestress reinforcing steel bar is arranged in the reinforcing steel bar reserved tunnel to connect a plurality of FRP-concrete combined panel prefabricated components to form an integral bridge panel structure in a needed size. The construction method comprises the steps: firstly producing the semiclosed FRP groove; arranging an FRP rib and an embedded corrugated pipe, and fixing the FRP rib and the embedded corrugated pipe; pouring concrete; splicing a plurality of prefabricated FRP-concrete combined deck components into a whole by utilizing the prestress after the strength of the concrete reaches the requirement. The factorization prefabrication and on-situ assembling of the FRP combined bridge deck are realized, the structure is simple, and the construction is convenient.

The toilet excrement discharge system for high speed train includes urinal, water jet, two pneumatic valves, small container, vacuum generator, solenoid valves, button, emergency switch, small water tank, electromagnetic water valve, vacuum and pressure detecting unit, etc. The urinal is flushed with jetted water in small quantity, and excrement is concentrated in the bottom of the urinal and vacuum sucked into one small container before pressurized to jet to railway bed via the discharge port or to the large container in the lower part of the train. The present invention can avoid blowing of excrement, reduce train pollution and rust and ensure safe running of the train and the health of passengers. The technology of the present invention may be used also in coach bus, hotel in water-lacking area, etc.

The invention relates to an agricultural shed plastic film, and particularly relates to a three-layer fragrant-flowered garlic. The shed plastic film provided by the invention is of a three-layer composite structure, wherein the outer layer is an anti-aging layer; the inner layer is a dripping fog disposal layer with the functions of dripping, and the middle layer is a light conversion layer formed by mixing resin, nano organic red additives and other functional additives. The agricultural shed plastic film provided by the invention has the advantages of good light quality regulating effect of the light conversion layer, small color attenuation velocity of the light conversion layer, great service life prolongation of the shed plastic film, obvious temperature preservation effect, crop pest disease and pest damage insulation and the like.

The invention relates to a manufacture art for a housing of a ceramics tap, which is prepared according to the following steps: firstly 10 to 20 portions of raw talcum, 60 to 70 portion of ripe talcum, 10 to 15 portion of clay, 5 to 10 portion of TiO or BaCO3 or the mixture of the two to carry through mixing are prepared and mixed together; then the original mixed raw materials can be calcined to 1320 to 1390 degrees, rubbed for 28 to 36 hours and then sifted to get ultrafine powder with 250 to 300 meshes; then the powder can be added into a paraffin liquid, the weight of which is 15 to 20 percent of that of the powder to make slurry; then the slurry can be shaped into a roughcasts of tap shells in required shape through an injection moulding technics forming technology; then roughcasts can be calcined, dewaxed, polished and glazed; finally roughcasts can be calcined to 1280 to 1350 degrees and cooled naturally. The invention can not generate any pollution during the manufacture and using processes and the product has the advantages of high temperature resistance, abrasion resistance, rust resistance and light weight, etc.

The invention discloses a garbage classified recycling treatment environmental-protection device. The garbage classified recycling treatment environmental-protection device comprises a second motor, astirring roller, a partition plate, a degradable garbage smashing area, a plastic smashing area, a third motor, a rotating rod, a smashing blade, a bearing, an air heater, an air pipe, sliding rails,a handle, a drawer, a partition net, a metal storage box, a leading-out sliding way, a separation area, a tooth guide rail, a protective shell, a forward and reverse rotating motor, a cylindrical gear, a mounting plate, rotating wheels, an electromagnet, a connecting rod, a rolling groove, a movable plate, a reset spring, a limiting plate and hinges. Through the partition net, the drawer can be mounted at the bottom of the metal storage box; drying agents are placed in the drawer so as to absorb moisture in air; the air heater blows hot air into the metal storage box through the air pipe so that moisture of metal can be conveniently evaporated for achieving dryness, the oxidizing reaction of the metal slows down, accordingly rust of the metal is relived, and the recycling rate of the metal is increased.

The invention provides a fluoride-free mold powder for low-carbon steel. The fluoride-free mold powder comprises the following materials by weight percent: 5-10 percent of Na2O, 3-10 percent of MgO, 3-10 percent of MnO, 3-10 percent of B2O3, 6 or less percent of AL2O3, less than 3 percent of Li2O, 1-3 percent of C and the balance of CaO and SiO2, as well as inevitable impurities, wherein the CaO / SiO2 is 0.8-1.3. The fluoride-free mold powder has the melting point of 950 DEG C-1150 DEG C and has the viscosity of 0.1-0.3 Pa*s at 1300 DEG C, and the crystallization rate measured by adopting the crystallizability detection method in the specification ranges from 10 percent to 50 percent. The fluoride-free mold powder can eliminate the adverse effect that the heat-transfer property of boron-containing residues in the using process is remarkably higher than that of traditional fluoride-containing residues, has very good environment protection and equipment corrosion reduction values, and can achieve industrial application in batch on the low-carbon steel slab continuous casting process, and the metallurgical effect completely reaches the standard of traditional fluoride-containing residues.

The invention provides a condensation prevention method and device for refrigeration equipment. The condensation prevention method comprises the steps: detecting the humidity of the external environment of the refrigeration equipment; judging whether the humidity is less than the preset humidity threshold value or not; if yes, setting the turn-on temperature of a storage room as first turn-on temperature, setting the turn-off temperature of the storage room as first turn-off temperature, and setting the speed of a compressor as first speed; if not, setting the turn-on temperature of the storage room as second turn-on temperature, setting the turn-off temperature of the storage room as second turn-off temperature, and setting the speed of the compressor as second speed. Thus, the refrigeration cycle of a refrigeration system is constant, the operating time of the compressor is prolonged, and the stop time of the compressor is shortened. The condensation prevention method can avoid long-time condensation, thereby overcoming the defects that the paint film of a box body is shed largely, the corrosion of the box body is accelerated, the service life of the refrigeration equipment is shortened, and the refrigeration effect of the refrigeration equipment is influenced.

The invention relates to a harmonic ingredient of high-power clean diesel oil, which is prepared by a cetane accelerant, a pour point depressant, a wear-resistant lubricant, a detergent dispersant, an oxidation stabilizer, a cosolvent and the like. The harmonic ingredient is based on improving the quality of the diesel oil, increasing the oil yield and reducing the production process, integrates assistants required in a harmonic process of the diesel oil, has the functions of reducing coagulation, increasing the cetane number of the diesel oil, improving lubrication and oxidation stability, cleaning efficiently and resisting static electricity, is non-toxic, free from heavy metal, low in addition and convenient to use, and can increase the power of the diesel oil greatly, reduce hazardous substance discharge of an automobile and reduce engine noise; the product quality is stable, the production process is simplified, the production and detection costs are lowered, and the mutual effect is controllable during production of an oil refinery; the quality of an oil product can be improved greatly for a refinery enterprise; and the benefit is improved.

The invention discloses a railway rescue station with smoke prevention and exhaust and personnel emergency evacuation functions. The railway rescue station is divided into an upper-layer structure, amiddle-layer structure and a lower-layer structure; the upper layer of the station is a smoke exhaust channel; the middle layer of the station is a rescue station body; the lower layer of the stationis an evacuation channel; a tunnel in the longitudinal range of the railway rescue station is composed of an upper-layer train tracking area and a lower-layer evacuation layer, and smoke exhaust portsare evenly formed in the upper portion of the inner side of a track of the upper-layer train tracking area; each smoke exhaust port is internally provided with a remote control smoke exhaust air valve; each smoke exhaust port is provided with a fire smoke detection module; the opposite sides of each smoke exhaust port are provided with directional jet fans; the upper portion of the train trackingarea is provided with mobile jet fan groups and movable fire extinguishing bins separately; escape staircases are arranged between the upper-layer train tracking area and the lower-layer evacuation layer. The railway rescue station mainly solves the problem that an evacuation platform cannot be arranged on a conventional rescue station for two two-hole single-line tunnel with short transverse distance, and the efficiency of smoke exhaust and personnel evacuation is improved.

The invention discloses an antifatigue basic magnesium sulfate cement which is composed of the following components in percentage by mass: 42-58% of magnesium oxide, 18-25% of magnesium sulfate heptahydrate, 10-15% of industrial waste residue powder, 5-13% of white slag, 3-5% of mineral admixture, 4-6% of straw, 2-4% of desulfurized gypsum, 3-5% of fly ash and 1-2% of thickening time control agent. The appropriate additives are added into the magnesium oxysulfate cement to form a new basic magnesium sulfate phase and generate the antifatigue basic magnesium sulfate cement which has completely different properties and characteristics from the traditional magnesium oxysulfate cement. The main hydration product is high-strength 517 whisker. The antifatigue basic magnesium sulfate cement belongs to novel special cement which has the advantages of whisker self-formation, high strength, high toughness, high folding ration, carbonization resistance, salt resistance, hydrothermal resistance, seawater resistance, impact resistance, fatigue resistance, reinforcing steel rust resistance, high durability and long service life.

The invention relates to the field of building materials, in particular to a doped organic indican concrete reinforcement corrosion inhibitor and application. The corrosion inhibitor disclosed by the invention is composed of the following components by weight percent: 5-15% of organic indicant, 5-10% of organic amine, 5-10% of organic alcohol, and 65-85% of water. When being used, the corrosion inhibitor disclosed by the invention is directly added into water to be dissolved according to the suggested amount of the corrosion inhibitor; simultaneously, the corresponding water amount is deducted according to the proportion of water in the components; the addition amount of the corrosion inhibitor disclosed by the invention is calculated according to the cement amount required for every cubic metre of concrete structure; the doped organic indican concrete reinforcement corrosion inhibitor disclosed by the invention is capable of effectively retarding corrosion of concrete reinforcements and prolonging the induction time of chloridion to locally corrode reinforcements and is free from obvious negative impacts in the structural performances of the concrete body; and the doped organic indican concrete reinforcement corrosion inhibitor disclosed by the invention can be widely applied to offshore, harbour, wharf, coastal and civil reinforced concrete buildings.

The invention provides an aluminum foil openable cover and a preparation method thereof, and belongs to the technical field of can-type package. The aluminum foil openable cover comprises a metal cover body and an aluminum foil packaging film, wherein an article taking-out hole is formed in the metal cover body; the aluminum foil packaging film is used for blocking the article taking-out hole, and is sequentially provided with a protection layer, a blocking layer and a heat-seal layer from top to bottom; a gloss oil layer is used as the protection layer; an aluminum foil layer is used as the blocking layer; and the heat-seal layer consists of 10 to 20 weight percent of polybutylene, 40 to 60 weight percent of high-density polyethylene (HDPE) and 20 to 40 weight percent of metallocene polyethylene. The prepared aluminum foil openable cover is high in sealing performance and high in openability.

The invention discloses a dovetailing cold-rolled steel composite plate. The plate comprises a surface plate with dovetail joint, a cold-rolled steel plate with dovetail groove and a heat insulating material, wherein the heat insulating material is arranged between an upper cold-rolled dovetail steel plate and a lower cold-rolled dovetail steel plate and embedded into the dovetail grooves of the upper cold-rolled dovetail steel plate and the lower cold-rolled dovetail steel plate; the upper panel is embedded into the dovetail groove on the upper part of the upper cold-rolled dovetail steel plate; and a lower panel is embedded into the dovetail groove on the lower part of the lower cold-rolled dovetail steel plate.

The invention provides a rail fastener system without elastic strips. A board lower resilient sleeper bearing is arranged above a gauge plate; a base plate is arranged above the board lower resilient sleeper bearing; a rail lower base plate is arranged above the base plate; a steel rail is placed on the upper surface of the rail lower base plate; a fixing piece is a nylon gauge clip; the nylon gauge clip is made of glass fiber reinforced nylon 66; the lower surface of one end of the nylon gauge clip is in contact with the upper surface of one end of a steel rail bottom; an inclined surface of one end of the nylon gauge clip is matched with an inclined surface of the upper surface of one end of the steel rail bottom; the lower surface of the other end of the nylon gauge clip is in contact with the upper surface of the base plate; and a screw spike sequentially penetrates in the nylon gauge clip, the base plate, the board lower resilient sleeper bearing and the gauge plate and then is matched with a concrete sleeper in a locked manner. The rail fastener system is simple in structure; the fastening strength of the rail fastener system without the elastic strips is equivalent to that of a rail fastener system with elastic strips, but the cost is reduced by a third; corrosion can be effectively relieved; the service life of the rail fastener system is prolonged; effects of noise reduction and shock absorption can be achieved; and the safety and the reliability of a vehicle in a running process are improved.

The invention relates to a burning coal additive that belongs to coal fuel additive technology field. The main feature is that mixes the salt combustion adjuvant and calcium oxide absorbent as the ratio of 4-10%:96-90%. The invention uses the combustion supporting and catalysis of Na and Cl that could be decomposed from melt salt. The CO2 from burning calcium oxide could absorb the SO2 from burning coal and finally form CaCO3. Thus, the aim of benefit for the environment would be achieved. It also has notable economical benefit and social benefit.

The invention relates to the technical field of an elevator and particularly relates to a detecting device for a water level of an elevator pit and a detection processing method thereof. The detecting device for the water level of the elevator pit comprises a lowest water level detecting sensor, a warning water level detecting sensor and a highest water level detecting sensor which are sequentially arranged on the elevator pit from low to high, wherein the lowest water level detecting sensor, the warning water level detecting sensor and the highest water level detecting sensor are electrically connected to an elevator master control plate; the elevator master control plate is electrically connected to a water pump which is arranged on the elevator pit; and the water level of the elevator pit can be subjected to three sets of water level detection and treatment, thereby being capable of efficiently reducing the damage and corrosion of escalator equipment and reducing the harm to the bodies of passengers.

The invention provides a method for compositely strengthening a steel pipe column through external sleeveing of circular steel pipe concrete fibre composite materials. The method is characterized by comprising the following steps that (1), polishing and derusting are conducted on the surface of an original steel pipe column; (2), an externally-sleeved circular steel pipe is installed on the periphery of the original steel pipe column, and the original steel pipe column is wrapped with the externally-sleeved circular steel pipe; (3), the fibre strengthening composite materials are twined outside the externally-sleeved circular steel pipe; and (4), after adhesives of the fibre strengthening composite materials are solidified, filling materials are poured between the original steel pipe column and the externally-sleeved circular steel pipe. According to the method for compositely strengthening the steel pipe column through the external sleeveing of the circular steel pipe concrete fibre composite materials, a steel pipe concrete structure is applied to the solidifying process of the steel pipe column, and a method for local solidifying or overall solidifying of a damaged steel pipe column through externally-coated steel pipe concrete is provided; when local solidifying is conducted, the externally-sleeved steel pipe mainly has a hooping effect, and when overall solidifying is conducted, the externally-sleeved steel pipe can jointly bear the pressure and has the hooping effect, so that a new thought is provided for the solidifying method of the steel pipe column.

The invention discloses a chloride ion adsorption agent for a reinforced concrete structure and a preparation method thereof. The adsorption agent is prepared from the following ingredients in percentage by mass: 20 to 30 percent of cenosphere, 11 to 18 percent of mesoporous molecular sieves, 7 to 14 percent of nanometer SiO2, 4 to 8 percent of regenerated active carbon, 5 to 15 percent of calcium aluminate powder, 15 to 25 percent of calcined kaolin and 12 to 20 percent of aluminoferic cement clinkers. The chloride ion adsorption agent has the advantages that all ingredients are scientifically matched; the synergistic effect is achieved; harmful ions such as chloride ions are subjected to physical absorption by a large area of the chloride ion adsorption agent; the ingredients and the chloride ions form chemical bonds; Friedel salt is generated; the content of free chloride ions is reduced, so that the corrosion on steel bars in the reinforced concrete structure is reduced; through the physical filling effect, the reinforced concrete compactness is improved, and the harmful ions such as chloride ions are prevented from entering the inside of concrete; gel substances are generated through the volcanic ash effect, and the space originally occupied by water is filled, so that the compactness and the strength of the reinforced concrete are improved.

The application provides a method for preparing a layered bimetallic hydroxide passivation film in situ. According to the method, the layered bimetallic hydroxide passivation film grows on the surfaceof an iron-based substrate in situ in one step by utilizing a hydrothermal method and in combination with urea decomposition; a hydrothermal reaction is performed on the iron-based substrate obtainedby pretreatment and a reaction solution containing urea, a divalent metal nitrate, and a trivalent metal nitrate to grow the layered bimetallic hydroxide passivation film; the preparation method is simple in technology; further, the thickness of the passivation film can be controlled by controlling a reaction time and a reaction temperature; thus, the anti-corrosive protection of a reinforcing steel bar is achieved; the excessive pretreatment does not need to be performed on the reinforcing steel bar in a reaction process; the preparation of the layered bimetallic hydroxide passivation film can be easily realized by adopting a one-step in-situ synthesis urea decomposition hydrothermal method; and the method is simple, convenient, easy to operate, energy-saving, environment-friendly, further, low in cost, and suitable for wide industrial production.

The invention relates to the technical field of municipal engineering, in particular to an extrusion type closing method for a joint of pecast concrete utility tunnels. The technical scheme provided by the invention is that nut fasteners are clamped on profile steel members and are screwed with bolts; by tightening the bolts, a gland compresses a water stop airbag, the water stop airbag expands and compresses water stop belts and further sealing water resistance of the joint of two pecast concrete utility tunnels is realized. The extrusion type closing method for the joint of the pecast concrete utility tunnels, provided by the invention, can realize sealing water resistance and has the advantages of simple structure, high construction speed and low cost.

The invention discloses a method for reinforcing a foundation bolt of an iron tower, belonging to the field of communication infrastructure maintenance. The method comprises the steps: determining the quantity and diameter of reinforcing steel bars; removing rust on the surface of an original foundation bolt, coating the surface with a protective coating, and padding a supporting block under a bottom flange; drilling steel bar embedding holes corresponding to the quantity of the reinforcing steel bars in the top surface of original foundation concrete, wherein the steel bar embedding holes are uniformly distributed along the outer circumferential direction of the original foundation bolt; cleaning the steel bar embedding holes and pouring an anchor adhesive into the steel bar embedding holes, and then inserting the reinforcing steel bars; chiseling the contact surface of the original foundation concrete, and then binding the reinforcing steel bars to form a steel bar cage; and setting up templates on the outer side of the steel bar cage and pouring concrete. Compared with the traditional demolition and reconstruction scheme, the method has the advantages that the cost is reduced by 90% or over, and the communication operation cost is greatly saved; the service needs of operators can be seamlessly connected, and no influence on communication exists.

The invention discloses a method for maintaining the profiled steel sheet roofing, comprising the following steps of: (1) closing and repairing seepage parts; (2) fixing a special bracket support seat and arranging a support seat at the position above a wave trough purline of the traditional profiled steel sheet; (3) sticking a temperature-insulating material and attaching the temperature-insulating material to the upper surface of the temperature-insulating material according to the wave shape of the temperature-insulating material to form a heat-insulating layer; (4) fixing the special bracket and brackets among sheets; and (5) overlapping and fixing novel profiled steel sheets with the same sheet type; covering the novel profiled steel sheets with the same sheet type as the traditional profiled steel sheet above the special bracket and brackets among the sheets; and after finishing the fixation, closing all fixed nodes by using a sealing material. The invention improves the heat resistance of the traditional profiled steel sheet, improves the condensation phenomenon at the bottom of the traditional profiled steel sheet and reduces the continuous corrosion of the traditional profiled steel sheet; meanwhile, by overlapping a novel layer and an old layer to construct the stress, the strength of the roofing of the respiring area can be improved, thereby the aim of repairing and reinforcing the roofing in a state without stopping production can be achieved.

The invention discloses ultrahigh-property concrete which comprises the following components by weight: 500-850kg / m<3> of cement, 50-150kg / m<3> of coal ash, 80-150kg / m<3> of silicon ash, 1000-1300kg / m<3> of sand, 80-160kg / m<3> of a steel fiber, 20-60kg / m<3> of a polymer emulsion, 60-180kg / m<3> of water, 30-40kg / m<3> of a water reduction agent and 0.1-1kg / m<3> of filming aids. By adopting the ultrahigh-property concrete, the waterproof anti-seepage property and the overall strength can be remarkably improved. The invention further provides a preparation method which is easy to implement and capable of preparing the ultrahigh-property concrete which is rapid and convenient to prepare, environmental-friendly and energy-saving and low in cost.